Glossary for Geospatial Analysis

G Glossary L O S S A R Y Glossary for Geospatial Analysis

P L U T F D R YG SJ M B WH Z

I Q E C A K X N

with the TNT products Glossary for Geospatial Analysis Before Getting Started TNTmips is MicroImages’ flagship product for geospatial analysis. TNTmips is used in more than 150 nations around the world for geographic information analysis (GIS), advanced image processing, CAD, desktop cartography, electronic atlas preparation, and other spatial database management and visualization applications. TNTmips offers a level of data and process integra- tion that is unmatched in any other professional system. And you can use TNTmips on Windows and Macintosh computers with exactly the same set of features and user interface on each platform. TNTmips is the most technically advanced and easy to use professional system on the market. This Glossary defines the specialized technical vocabulary that is associated with TNTmips. The staff of MicroImages uses many of the terms included here with slightly different meanings than those in general usage. These definitions establish a common vocabulary for communicating with other TNTmips users and MicroImages’ technical support staff. Because this glossary was compiled beginning in 1990, some of the terms may seem distinctly out of date, such as optical disk and WORM drive. Think of this glossary as an historic reference in that respect. Definitions credited to (Random House) are from The Random House Dictio- nary of the English Language, Second Edition, Unabridged.

More Documentation This booklet is adapted from the glossary in the TNTmips reference manual. You may wish to consult the reference manual for additional information. TNTmips Pro, TNTmips Basic, and TNTmips Free TNTmips comes in three versions: TNTmips Pro, TNTmips Basic, and TNTmips Free. HyperIndex Linker is available only to customers using TNTmips Pro. If you did not purchase the professional version (which requires a software license key), you are using TNTmips Free or TNTmips Basic, which limit the size of your project materials.

MicroImages’ Scientific Writers, 9 May 2012 © MicroImages, Inc., 1990–2012

MicroImages’ web site is your source of the newest tutorial booklets on a wide variety of topics in geospatial science. You can download the tutorial booklets, an installation guide, sample data, and the latest edition of the TNT products. http://www.microimages.com

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are present in white light is easily demon- strated using a prism, which separates — A — white light into the spectrum of colors of which it is composed. White light can AAT: ARC/INFO Coverage attribute table; also be produced by mixing complemen- created when vector objects are exported tary colors. Absence of radiation or rela- to ARC files. tively low radiation at all wavelengths of absolute colorimetric rendering: A ren- human visual sensitivity will yield black. dering intent in which the colors in the A predominance of radiation in a particu- source gamut (displayed image) that are lar range of wavelengths will yield a color available in the destination gamut whose intensity is proportional to the (printer) are rendered exactly as they are level of radiation. (See also: subtractive and colors outside the destination gamut color) are replaced by the nearest available color aerial photograph: see airphoto. at the outer limit of the destination affine: Transformation of geodata that maps gamut. White may or may not be repro- lines to parallel lines and finite points to duced exactly. finite points. accelerator: A key or key combination that agronomy: The study of crop and soil sci- invokes the action of some component ences including crop breeding, genetics, (like a push button or menu selection) and cytology; plant molecular biology and regardless of the position of the location plant molecular genetics, crop physiol- cursor. An accelerator can activate a ogy and metabolism; crop ecology, pro- menu selection even if the menu is not duction, and technology; turf grass; crop open. quality and utilization, agroclimatology accuracy: The measurement for an X-Y and agronomic modeling; soil physics; soil digitizing tablet of how close the reported chemistry; soil microbiology; soil fertil- coordinates for any given point come to ity and plant nutrition; soil genesis, mor- the point’s actual location. Accuracy is phology, and classification; soil mineral- stated in terms of the possible distance ogy; and soil management. for error (for example, ±.01 or ±.025). airphoto: A photograph taken vertically active area: The area on an X-Y digitizing from the air. Any type of camera may be tablet that is sensitive to the pointing used, but single-lens frame cameras are device. most commonly used. Airphoto images active element: The last vector, CAD, or can be available to users as paper prints, TIN element added to a selection set in transparent film, or digital computer files. single select mode. If the selection set is An airphoto includes significant horizon- established using a selection tool that al- tal displacement introduced by camera lows multiple elements to be selected at characteristics, tilt, nearness to the tar- one time, such as the rectangle or circle get scene, and variations in elevation of tool, the active element is the element the target terrain. with the lowest element number among airslide: A 35mm slide taken vertically from those selected. the air. additive color: Colors perceived by the airvideography: The growing field of mak- human eye that are created by mixing ing measurements from digitized frames different colors of light, or visible radia- of vertical airvideo images. These mea- tion are produced in an additive manner. surements can be used for managing agri- The colors of the images produced on a cultural and natural resources, making tax color display screen or by a color projec- assessments, and monitoring environmen- tion onto a white screen are examples of tal degradation among other uses. additive color. When all wavelengths, or airvideo image: An image acquired verti- colors, of visible light are mixed, white cally with a color, monochrome, or color- light is produced. That all visible colors infrared video camera and recorder.

page 3 Glossary for Geospatial Analysis albedo: “The ratio of the light reflected by hand on an analog watch “sweeps” around a planet or a satellite to that received by the dial and you can tell time on an ana- it” (Random House). This definition can log watch even if it has no numbers on be generalized to any object, such as a the face. Another example is a thermom- part of the earth’s surface or atmosphere, eter that displays temperature using a a leaf, a soil element, and so on. needle or liquid can indicate fractions of algorithm: A numerical scheme applied to a degree, as well as provide information reach a solution of a problem. about relative warmth by the position of the dial or height of the liquid. On the aliasing: (referring to a graphic display of other hand, this continuous analog in- lines) A line that is drawn digitally, cell by formation is harder to copy, store, ma- cell, with fixed, uniform color and inten- nipulate and reproduce dependably. Any- sity is said to be aliased. The cells are one who has ever listened to a copy of a easily resolved by the observer’s eye so copy of a copy of a cassette tape has the line is seen to have a jagged, stair-step first-hand knowledge of analog informa- appearance. (See also: anti-aliasing.) tion degradation. For this reason, much allocation: The movement of materials into analog information (video, audio, or field or out of a number of centers, all of which and laboratory measurements of tem- serve the same purpose, such as schools, perature, pressure, voltage, radiation, and fire stations, or warehouses. The Net- so on) is converted to its digital equiva- work Analysis process includes an allo- lent. (See also: digital, digitizer) cate mode. angle impedance: The opposition to flow alphabetic: A written language that uses a around a turn in network analysis. Angle fixed, ordered set of phonetically-related impedance is determined by node prop- characters is said to be alphabetic. Most erties and your choice of lines for ap- Western European languages are alpha- proaching or leaving the node. betic (Latin-based), as are Greek, Hebrew, anisotropy: A distribution of point geodata Arabic, Russian, Turkish, and Indian. in which the probability of encountering Modern Korean (Hangul) is an alphabetic other points starting from any given replacement for Chinese-based character point is not equal in all directions. Anisot- writing which was used until the 1500’s. ropy can apply over short or long dis- Modern non-alphabetic languages include tances. Chinese and Japanese, in which charac- ANSI: American National Standards Insti- ters may be syllabic constructs histori- tute is a national coordinator of volun- cally derived from pictographic arche- tary standards activities and acts as an types. While they use a basic set of char- approval organization and clearinghouse acters (a few thousand) for most writing, for consensus standards in the USA. the character set is not strictly limited to ANSI works closely with international a fixed number of characters. organizations, particularly ISO, for the AM/FM: Automated Mapping and Facilities development and approval of interna- Management. A geographic information tional standards. system designed for the optimal process- antarctic circle: A small circle of the earth ing of information about utilities and in- parallel to the equator drawn on maps at frastructures, such as power lines and wa- 23° 27' from the south pole (66° 33' S). ter and telephone networks. The exact location of the antarctic circle analog: Information stored and processed as varies slightly since it is defined by the signal intensity or other measurement of sun’s furthest southern declination (po- a continuous physical variable. Analog sition at winter solstice) from year to information processing translates and rep- year. resents slight increments in data easily anti-aliasing: (referring to a graphic dis- and conveys information by relative po- play of lines) Anti-aliasing removes or sition without relying on the numeric value greatly reduces the jagged, stair-step ap- necessary to convey the same informa- pearance of a digital line. This stair- tion digitally. For example, the second

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stepping is caused by plotting a uniform arcsecond: “The sixtieth part of a minute of color and intensity line on a display de- angular measure often represented by the vice whose minimum resolution or cell sign “, as in 30”, which is read 30 sec- size is easily resolved by the observer’s onds” (Random House). (See also: de- eye. gree, minute.) Anti-aliasing smoothes out the jagged arctic circle: A small circle of the earth par- edges of the line by filling in some of the allel to the equator drawn on maps at 23° intermediate and flanking cells in lower- 27' from the north pole (66° 33' N). The intensity colors. (See also: aliasing) exact location of the antarctic circle var- API: An Application Program Interface is a ies slightly since it is defined by the sun’s set of system calls or routines for appli- furthest northern declination (position at cation programs to access services from summer solstice) from year to year. operating systems or other programs. Area correlation: A DEM extraction method APIs are fundamental to client/server that methodically traverses a pair of ste- computing. reo images, working from the initial set API key: A mechanism used by Google to of correlation points supplied by the user, authorize users to access the Google and building a correlation model from new Maps API to embed the Google Maps points of correlation that it finds. geoviewer in a web page. areal extents: Size, or magnitude, of an area APPLIDAT: A unique combination of SML represented digitally as features in either scripts and Project File geospatial data image or geometric format. Areal ex- created in TNTmips. An APPLIDAT tents of component files are recorded in (APPLIcation plus DATa) can be LDS files when they are generated by a launched from a desktop icon that opens TNT process. the preselected geodata and presents a ASCII: American Standard Code for Infor- custom icon toolbar. mation Interchange (pronounced arbitrary georeference: A georeference “askee”). The 7-bit (128 characters) used that uses a matrix rather than control as a computer’s alphabet. The Latin al- points. Raster, vector, CAD, or TIN phabet character set encoded into digital objects can have an arbitrary values between 0 and 127 includes lower- georeference. An arbitrary georeference case and uppercase letters, the numerals is created when an object with no 0–9, English punctuation marks, special georeference is used as a reference layer symbols (such as @#$%^&*) and non- for creation of a new object in TNT’s displaying characters often used as printer Editor or the new object is created in a control codes. The eighth bit, giving val- process such as Auto-Trace from a non- ues from 128 to 255, is used in a non- georeferenced object. An arbitrary geo- standard fashion and is not part of the reference allows you to correctly display standard ASCII code. PCs normally have related objects together. This type of the “extended” character set in their sys- georeference is currently referred to in tem font for digital values from 128 to the TNT products as local engineering. 255. The characters used for values from 128 to 255 for TNTmips display screen archive: A preserved collection of historical fonts are unpredictable but can be dis- information, such as a backup of your played in the font style window. Some data. fonts have no characters in this range ARC/INFO: A vector-based Geographic In- while others have characters for some or formation System (GIS) developed and all of these values. ASCII is a proper marketed by ESRI, Inc. for use on work- subset of Latin-1, Unicode, and ISO stations. 10646, which are the 1-byte, 2-byte, and ARC/INFO extent file: The name of the 4-byte standards for international char- data file used by ARC/INFO which con- acter encoding. tains arc, node, and polygon data ele- The term “ASCII file” is often used to ments. mean a text-only file. Documents in

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most word processors are not text-only time during the assembly of your files, since they include header informa- geomashup you can immediately preview tion and formatting characters. However it in any popular Windows or Mac most word processors have an export or browser (Firefox, Safari, Internet Ex- print-to-file utility that will convert a plorer, Chrome, and Opera) to test the document into a text-only ASCII format. current design and operation. The pro- ASCII file: A text-only file. Documents in cess also creates the HTML file with Java- most word processors are not text-only Script required for your current layer files, since they include binary header in- choices and tools. formation and formatting characters. assignment statement: A line in a query However most word processors import so- or script that changes the value of a style called ASCII files and have an Export, drawing variable. Example: size = 5. That Save/Text-only, or print-to-file utility statement changes the value of the size that converts a document into an “ASCII” variable to 5. (The size variable con- format. However, these files are not true trols the size at which node elements are ASCII files because they may include the drawn). Assignment statements may be characters from 128-255. The charac- used in vector display and several other ters in this range are different between processes that let you assign drawing platforms such as PCs and Macintoshes styles by query. and even from font to font with a plat- attribute: A piece of information describ- form, and are not part of the standard 7- ing an element in a coordinate data ob- bit ASCII code. (See also: ASCII.) ject or a raster cell. Each element in a ASCS: Agricultural Stabilization and Con- vector, CAD, or TIN object may be as- servation Service. Merged with other ag- signed one or more attributes. Element ricultural agencies in 1994 to create the attributes include internal information Farm Service Agency. and information in an associated data- aspect: A parameter that is associated with a base. Attributes can include such qualities feature of a topographic or other three as drawing style, element number, and dimensional surface. Aspect is the com- classification category, such as “inter- pass direction (usually from north) for mittent stream” or “wetland.” the perpendicular to the tangent to the attribute table: A tabular object containing surface at some selected point. Aspect records and fields, or rows and columns. tells which direction a surface slopes mea- Each record, or row, represents one or sured in degrees from North in a clock- more geographic features and each field, wise direction. or column, represents one attribute of aspect ratio: The ratio of horizontal scale those features. to vertical scale for printing or display. AutoCAD: The most popular commercial For graphics and image processing, square Computer Aided Design (CAD) software cells/pixels are best (aspect 1:1). Some package written and distributed by display devices have a non-square aspect, Autodesk, Inc. This software supports which causes images to appear stretched the same display boards as TNTmips or distorted. Standard broadcast video has with its own display drivers. an aspect ratio of 4:3, which must be cor- autocorrelation: “The correlation of an rected in any framegrabbing or other digi- ordered series of observations with the tization process. same series displaced by the same num- Assemble Geomashup: The Assemble Geo- ber of terms” (Random House). mashup process in TNTmips (Main /As- auto-correlogram: A process in semble / Geomashup) allows you to mashup Hyperspectral Analysis. The Auto- your own tilesets with geodata layers from Correlogram process provides an esti- remote sources for viewing in a web mate of the spatial-spectral variability brower. You can choose base maps, over- of the hyperspectral image on a pixel by lay layers, the web mapping API to use, pixel basis. and the map controls to include. At any auto-name: Name for output file that is

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automatically assigned based on input or output object//file (depending on process, e.g., tile files use easting and northing coordinates of tile’s lower left corner, — B — output objects from vector merge are each named merge and appended by a backup: A copy of a file, set of files, or whole number if multiple output objects are disk for safekeeping in case the original is written to the same file). lost or damaged. AVHRR imagery: Advanced Very High band or spectral band: A range of wave- Resolution Radiometer imagery produced lengths of electromagnetic radiation. by NOAA satellites. Remote sensing devices commonly col- AVIRIS imagery: Airborne Visible/InfraRed lect images in discrete bands, such as vis- Imaging Spectrometer imagery. Multi- ible red, green, and blue, and the invisible spectral images of approximately 240 near-infrared. coregistered spectral bands collected by band interleaved: A type of geodata stor- NASA aircraft. age and reading for multiple bands. The azimuth: The angle defined by the inter- geodata is stored and read line by line. section of a map’s central line of projec- That is, the first line of the first band is tion with any meridian. If a map projec- followed by the first line of the second tion uses a central line that is oriented to band, the first line of the third band, and true north, such as a standard meridian, so forth through all bands . Then the the azimuth angle is zero. next line stored is line two of the first azimuth angle: Angular displacement from band followed by line two of the second North. band and so forth through all lines within all bands. azimuthal projections: (also known as Planar Projections) A class of map pro- band mapping: A spectral matching method jections that are constructed by placing in Hyperspectral Analysis. The Band a flat planar surface tangent to a single Mapping method compares unknown point on the globe, or by placing the spectra that you are analyzing to spectra globe to an intersecting (secant) plane. in a reference spectral library on the basis With azimuthal (or planar) projections, of the positions and relative depths of lines of equal distortion are concentric absorption features. around the point of tangency or the cen- band trailer bytes: Some image bands have ter of the circle of intersection. Most trailer information attached to the end azimuthal maps do not have standard par- of each band image. In the User-defined allels or standard meridians. Each map Raster Import process a user must tell the has only one standard point: the center. import process the length of this trailer Thus, the azimuthal projections are suit- in bytes so that the import process can able for minimizing distortion in a some- import the trailer information correctly. what circular region, such as Antarctica, band variance: One of three noise statistics but not for an area with predominant plots that can be produced in the length in one direction. Azimuthal pro- Hyperspectral Analysis process. The band jections include Orthographic, Stereo- variance plot shows the proportion of graphic, Gnomonic, Lambert Azimuthal the variance, or noise, that can be attrib- Equal-Area, and Azimuthal Equidistant. uted to each input band. azimuth spacing: The linear distance or bandwidth: A measure of the volume of data image scale in the along-track dimen- that can flow through a communications sion, which is perpendicular to the range link, or throughput. Bandwidth is mea- directions in a radar image. The resolu- sured in kilobits or megabits per second. tion of a synthetic aperture radar (SAR) (Kb/s, Mb/s). Also, a section of the elec- image in the azimuth direction is con- tromagnetic spectrum between two fre- stant and independent of range. quencies. For example, AVIRIS collects

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224 contiguous spectral bands with a band- raster objects usually store a scan of black width of 0.10 micrometers. lines on white paper, the results of barrier: A node that can not be crossed in thresholding a byte-oriented raster ob- the Network Analysis process. ject into two data ranges, a threshold of a particular color range, or a data mask. basin: (watershed analysis) The area draining to any particular point in the land- Bing Maps: Bing Maps is a web mapping scape (called a seed point); a subwatershed service provided by Microsoft with street or subcatchment. Standard basins in the maps for many cities worldwide. watershed process are generated using Bing Maps Custom Tile Overlay: “Cus- stream junctions as seed points, so a stan- tom Tile Layer” is the name Bing Maps dard basin is the area drained by a particu- uses to refer to the stucture of the tilesets lar tributary system of the main stream. that its API for an overlay. It conceptu- batch: A DOS batch file is a text file with the ally emulates the way in which Microsoft extension .BAT that contains one DOS stores its proprietary Bing Maps road and command on each line. When you enter aerial layers accessible over the Internet. the name of the batch file at the DOS Tiles for areas of the source image that prompt, the system performs each com- are to be treated as completely covered mand in turn. by the tile are usually *.jpg. Tiles are *.png where the area covered overlaps batch job: (TNTmips) A process or sequence the regular or irregular outer edge edge of of processes that is set up with Job Man- the source image or an inner edge for ager or another process to run unattended, missing internal areas. All tiles can also requiring no user interaction or supervi- be *.jpg or all *.png depending upon the sion. desired appear of the source image in the bathymetry: The science of measuring ocean, application. sea, and lake depths. biomass or total biomass or total plant baud rate: The speed of data transmission material: The amount of plant mate- between a computer and other devices rial per unit of ground area, recorded ei- measured in pulses per second. ther as wet weight or dry weight. It is Bézier curve: A polynomial curve bounded usually expressed in grams per square by four points, which form a “bounding meter, tons per acre, or metric tons per box.” Manipulating the position of the hectare. bounding points lets a user stretch and bit: The smallest unit of computer data position a smooth curved line in the de- having a single value of either “1” or sign of a graphic shape, such as the irregu- “0”. A contraction of the two words lar curving outline of a font character. “Binary” and “digit”. Binary data is 1- bilinear interpolation: A mathematical bit data. Computers normally manipu- method for interpolating a new cell’s value late bits at least 8 at time. A group of 8 within a 2 x 2 neighborhood of cells. Bi- bits is called a byte. A computer’s pro- linear interpolation is used in resampling cessing power is often measured by the a raster object to create a new raster ob- number of bits it handles at once. The ject with a different cell size, orientation, earliest PC’s were 8-bit machines. More or internal geometry. (See also: interpo- recently processors and data structures lation.) for 16-bit, 24-bit and 32-bit data have become common. binary: A base 2 number system that uses only the data values “0” and “1.” Each bitmapped font: A font specification in place represents a power of 2, so, for ex- which each character is described pixel ample, the decimal number 6 is represented by pixel for a particular font size. Thus, in base 2 as 110 (= 1x4 + 1x2 + 0x1). bitmapped fonts do not rescale easily: at smaller sizes, pixels are left out, and at binary raster object: A raster whose cells larger sizes, pixel reduplication causes a contain only the values “0” (typically dis- jagged, blocky, low-resolution appear- played as black) or “1” (white). Binary ance. (See also: outline font.)

page 8 Glossary for Geospatial Analysis bits per pixel or pixel depth: The number rasters for a feature of interest (like all of data bits each pixel represents. In 8- the dark brown areas representing bare bit contexts, the pixel depth is 8, and soil). each display pixel can be one of 256 All of the data triplets in the three raster possible colors or shades of gray. With a objects are tested to determine if they 24-bit raster (or with three coregistered represent a cell inside the boxcar. All the 8-bit rasters) the pixel depth is 24, and inside cells may then be displayed or oth- 16,777,216 colors are possible. erwise recorded as “classified.” BLM: Bureau of Land Management of the Boxcar classification is not restricted to USDI. sets of three rasters. It may be used with BLOB: Bianary Large OBject. The data any number: using 2 rasters designs a 2- type of a field in an RDBMS table that dimensional “boxcar” test in a 2-dimen- can store large image or textual data as sional space, and using “n” rasters defines attributes. an n-dimensional “boxcar” test in n-di- block: A block is a grouping of CAD ele- mensional space. ments and attributes that can be manipu- box cursor or location box: Marks the fo- lated as a whole. All CAD objects con- cus for keyboard activity in a window. tain at least one block, the Main Block. breakline: A linear feature that controls the When a block (such as the detail for a surface behavior of a TIN in terms of door frame) is used multiple times in a smoothness and continuity. Breaklines drawing, the block description is stored are always maintained as linear features once, and each insertion point refers to in a TIN. that source. brightness: The physical property indicat- block insertion element: A block that is ing how much electromagnetic radiation inserted into another CAD block and, is being reflected or radiated by a chosen thus, acts as an element. point. Brightness is similar to the HIS board: An electronic circuit board installed property of Intensity, and is used in the in a microcomputer to add hardware fea- HBS color model. Brightness is also the tures. (See also: display board.) property computed from Landsat MSS or Boolean expression: A type of expression TM images by Kauth’s greenness, bright- that reduces to a logical (true or false) ness, wetness transformations. (See also: condition that contains logical expres- HBS, HIS.) sions (e.g., Flowrate > 50) and Boolean BSD license: A family of permissive, free operators. software licenses modeled after the Ber- Boolean operators: An operator that speci- keley Software Distribution license. fied how to combine simple logical ex- BSpline : A curved smoothing that can be pressions into complex logical expres- applied to a line. A BSpline is calculated sions, such as OR, AND, and NOT. For by a polynomial equation. Different types example, Flowrate > 50 AND Depth < of BSplines, such as Cubic BSpline and 100. Exclusive Or (XOR) and AND NOT Quadratic BSpline, can be calculated from are also Boolean operators. different types of polynomial equations. boxcar classification or boxcar interpre- bubble: A small island (often just a cell or tation: The simplest form of auto- two) of background color in the stream mated image interpretation whereby of a thinned, binary line in a raster. Bubbles three data ranges are selected for three are artifacts of the thinning process and coregistered images (like red, green, and result from binary lines that include un- blue). The three data ranges define a noticed cells of the background color af- boxcar shape if plotted on three dimen- ter thresholding. Bubbles must be repaired sional perpendicular axes that represent by raster editing or else the automatic possible data values in red, green, and vectorization process will create small, blue. The ranges are usually selected to incorrect polygon elements from them. represent the color variation in the three buffer: A portion of computer memory set

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aside for quick temporary storage. A buffer B/W photo, B/W image, B/W display, or is commonly used to store data on its way B&W: A black and white photograph or to or from a hardware device such as a some other monochrome image rendered disk drive. The buffer lets the computer in black, white, and shades of gray. “save up” access operations and not be byte: A data element made up of 8 bits and slowed down by waiting on the hardware having 256 possible values. In text-ori- to respond at every step. ented processes, each byte represents one buffer zone: A border area that acts as a character of text. In 8-bit raster pro- barrier separating or surrounding an area cesses, each byte represents one cell value designated for special protection. Some and may correspond to one pixel on the states have legislated buffer zones around image display. (See also: bit, exabyte, certain wetlands to prevent damage to the gigabyte, kilobyte, megabyte, pecabyte, local ecosystem. terabyte, yottabyte, zettabyte.) bug: An error in a computer program or in a byte-oriented or 8-bit raster object: A piece of electronics that causes it to mal- raster in which each cell is represented function. MicroImages prefers to call by one byte (8 bits) and can therefore these by their real name—errors. assume 256 possible values. building points: Creating and/or adding points in a vector object from imported coordinate data (like text files that contain pairs of coordinates, or database files — C — with fields representing pairs of coordinates). C and C++: High-level programming lan- bus: The circuit channel or path a computer guages. uses to move data and send signals be- CAD:Computer Aided Design. CAD origi- tween devices. A microcomputer’s bus nated on larger, dedicated workstations architecture determines what kinds of pe- and minicomputers and has now migrated ripheral circuit cards can be plugged into to microcomputers. In its simplest sense, its expansion slots. DOS and OS/2 com- CAD is used for computerized drafting. puters have four varieties of bus architec- Many CAD systems also provide more ture: PC, AT (also called ISA), EISA, and advanced features like solid modeling and Micro Channel. The original PC bus simulation. handles 8-bit data. The AT bus doubled the data width to 16 bits and became the cadastre: “An official register of the own- industry standard (thus ISA, for Industry ership, extent, and value of real prop- Standard Architecture). IBM introduced erty in a given area, used as a basis of the PS/2 with a proprietary bus, the 32- taxation” (Random House). bit Micro Channel. Other vendors coun- CAD Editor: The process used in TNTmips tered with a 32-bit Extended ISA (the for creating and editing CAD objects. EISA). The PC/ISA/EISA buses are back- Input can be from your computer’s mouse ward compatible: that is, expansion cards or from an X-Y digitizing tablet. designed for an older bus will normally CAD object: A CAD object, in RVC format, work in a newer bus slot. Thus, an 8-bit like a vector object, is composed of co- display board from a PC bus works in a ordinate data, but uses a different data 16-bit ISA slot or a 32-bit EISA slot, but a structure. A CAD object has a free-form 16-bit display board for an ISA bus does topology, so it may be useful for applica- not work in an 8-bit PC slot. tions that do not require an exact de- button: A control component in a window scription of the relationships between the that is activated by positioning the mouse elements in the object. CAD object to- cursor over it and pressing the left mouse pology does not reconcile things like line button. A button may be one of several intersections, polygon overlap, and poly- types: push button, radio, toggle, check, gon islands. cascade, or option. A CAD object also allows for descrip-

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tions of geometric shapes. For example, low you to design custom map symbols in a vector object, a circle is always stored for many applications. as a polygon, and at a high enough mag- cascade button: A type of button that dis- nification, the discrete point and line el- plays a cascading menu. A cascade button ements become visible. By contrast, a is typically a selection on a parent CAD object stores a circle by its center pulldown menu. It includes an arrow point and radius. Thus, at any magnifi- graphic that points in the direction the cation, it looks circular. cascading menu appears. Since they have reduced topological con- cascading menu: A submenu that opens straints, CAD objects generally require from a selection on a parent pulldown or less storage than their vector object coun- popup menu that provides selections that terparts. [See also: element (CAD).] supplement the parent selection. calibrate or cell size calibration: To es- catchment: (watershed analysis) The entire tablish scale or cell size (for a raster) for area drained by a stream and all of its an object in a project file. Once a raster, tributaries, with all runoff draining to the vector, or CAD object has been calibrated, same outlet. In nature the outlet may be a accurate measurements can be determined lake, the ocean, or other water body. In and displayed. (See also: georeference) the Watershed process, the outlet may calibrated image map: See: image map. also be the point where a particular flow cap style: The ends of dashed line segments, path intersects the spatial boundary of which are components of line patterns, the elevation raster being analyzed. Syn- are caps. You can assign a style to this onym: watershed. cap when you are creating or editing a categorical data: Data in a raster object is line pattern in the Style Editor. The cap said to be categorical if it cannot be rep- can be round or flat. resented by a continuous surface, since capacity: The number that can be accom- intermediate terms cannot be derived with modated by a center in network analysis, meaningful results. Example 1: soil type such as the number of students a school data cannot be interpolated, since a soil can accommodate, the quantity of per- type 14 and a soil type 15 cannot sensi- ishable goods that can be delivered in one bly be averaged to derive a soil type 14.5. day, the number of seats in a theater, or Example 2: feature classification data can- the number of parking spaces at a shop- not be interpolated, since a cell assigned ping mall. membership in the feature “corn” cannot sensibly be used in any process that Cartesian coordinate system: A two-di- averages it with a cell assigned member- mensional, planar coordinate system in ship in the feature “wheat.” which x measures horizontal distance and y measures vertical distance. Each point Do not confuse the terms “categorical on the plane is defined by an x,y coordi- data” and “category”—they have differ- nate. Relative measures of distance, area, ent and distinct meanings. and direction are constant throughout the category: (in Feature Mapping) A subdivi- Cartesian coordinate plane. sion within a region of interest (which capture: To freeze and digitize a standard also has a particular meaning in reference video input signal (such as VHS tape or to Feature Mapping) that lets you divide broadcast video). Some microcomputer the study site so that the measurement display boards offer video capture. (See data in the output text file will be orga- also: frame-grabbing.) nized geographically. So, if you have defined a region of interest as the wetland cartography: The art or science of making duck habitat along a river floodplain, you maps. might want to divide the wetlands into CartoScript: A script written with the car- categories: perhaps ownership areas (like tographic scripting language in the TNT refuge lands, private ownership, and ease- products, which provides a complete and ment areas). Then the text output file flexible set of drawing functions that al- would break down the wetland feature

page 11 Glossary for Geospatial Analysis

measurements by ownership area. If you materials or people are brought or from do not define categories, TNTmips treats which materials or services are distrib- the entire region of interest as a single uted. category (and does not subdivide the fea- central meridian: The north-south me- ture measurements in the output data). ridian of a map projection around which Do not confuse the terms “categorical the map is centered. data” and “category”—they have differ- centroid: “The point that may be consid- ent and distinct meanings. ered as the center of a one- or two-di- CAT scan: A medical diagnostic image pro- mensional figure, the sum of the displace- duced by Computer Aided Tomography. ments of all points in the figure from CCITT Comité Consultatif such a point being zero” (Random Internationale de Télégraphique et House). Téléphonique (International Telegraph CGA: Color Graphics Adapter. An early and Telephone Consultative Committee): microcomputer graphics subsystem de- A standards organization that has devel- veloped for the IBM PC. The CGA was oped a series of communications proto- hampered by low resolution and limited cols for the facsimile transmission of color selection. It has been superceded black-and-white images over telephone by EGA, VGA, SVGA, 8514/A, and XGA. lines and data networks. The CCITT ac- (See also: EGA, VGA) ronym in TNTmips represents a type of CGI: Common Gateway Interface. lossless raster compression that is used for 1-bit images. CGM: Computer Graphics Metafile is a graphic image exchange format. CD-R: Compact Disk-Recordable. A 5" optical disk that can be written to by a CD change image: An image produced using burner. raster algebra that shows change over time between coregistered images. CD-ROM: Compact Disk, Read-Only Memory. A 5" optical disk containing character: An element used for the graphic prerecorded data sets. representation of data (such as a letter, numeral, or symbol) or control of data CD-RW: Compact Disk-Rewritable. A 5" (such as a tab, space, return, or enter). optical disk that can be written to by a Each element has a corresponding char- CD burner in multiple sessions. acter code in the Unicode table. cell: One value in a raster that corresponds check button: A square button in a pop-in to a specific area on the ground. A raster window that presents one selection in a cell may contain a value that describes group of on/off options. When a check the elevation above sea level at one posi- button is “on,” it appears “pushed in”. tion in a survey site or the intensity of Clicking on one check button does not red radiation for a pixel in a video image. effect any other check buttons in the For convenience, a raster cell is usually group. (See also: radio button.) thought of as square or rectangular, although many image collection devices ac- chip: Commonly, any integrated circuit logic tually measure circular or elliptical areas. component of a computer. If a raster object is created from a screen CIR image: Color-infrared image. Color- image, each cell value represents one pixel. infrared images may be collected by an cell size: The dimensions of the area on the electronic scanner or a camera that uses ground to which a raster cell value ap- special film with sensitivity from green plies. A cell size of 30 meters signifies through infrared. The photographic in- that the value in each cell of the raster frared radiation just beyond the range of object applies to a 30 x 30 meter area in human vision is then displayed as red. the study site. Normal red from the scene becomes green, and green becomes blue. Normal cell size calibration: The transfer of cell blue in the scene is filtered out and not size information to a raster. recorded. CIR images are used to show center: A point within a network to which

page 12 Glossary for Geospatial Analysis

the vigor of plant life. Healthy vegeta- registered, overlapping, rasters are reduced tion appears red, while distressed or dam- to a single raster, which is referred to as a aged vegetation may look pink, tan, or cluster map. The rasters used in cluster- yellow. (See also: color-infrared image) ing represent analytical data (such as im- class: (raster) A set of all image features of ages and elevations). Different cluster- the same type. As part of the interpre- ing methods (such as K-means, Fuzzy C- tive process, the user names a class to means, and Isoclass) use varying logic to identify the type of material it contains, accomplish this mapping and dimensional like “corn,” “bare soil,” “wetland,” or reduction. In general, all of the methods “urban.” In a set of coregistered raster use the concept of testing multiple values objects, a grouping of cells with similar for each cell against all other cell values sets of values. A class normally corre- to determine which subpopulation each sponds to a specific land cover type with cell is most similar to and should be a restricted set of biophysical proper- grouped with. All clustering methods first ties. make a preliminary set of groups by testing all cells or a sample of them. They class center The set of raster values that then proceed by various methods to test define the mean vector for the class in individual cells and dynamically redefine feature space. the clusters until every cell is satisfacto- classification: Grouping cells (often by rily assigned a cluster membership in a color characteristics) from coregistered single cluster, which is recorded at that rasters to map the location and type of cell’s position in the cluster map. The image features (like type of crop, sur- maximum number of clusters to form and face cover, and map line type). the number of refinement iterations is class list: A subobject containing a list of usually controlled during setup. (See also: classes associated with a vector or CAD labeling, unsupervised classification) object. cluster labeling: Identifying and grouping class numbers/renumbering (LAS): the clusters in the cluster map raster object that result from any kind of auto- client/server: A software system has a cli- mated image interpretation. The user ent/server architecture when there is a chooses labels (names for types of fea- central processor (server) that accepts tures) based upon his or her knowledge of requests from multiple user processes (cli- the areas or materials in the image. Use ents), such as TNTserver and TNTclient. the TNTmips Feature Mapping process clip: Clipping limits the extents of a layer or to label (and possibly combine) the clus- group for the purpose of display. Clip- ters. ping extents can match a reference ob- cluster map: The output raster created by ject or use geographic coordinates. clustering or by unsupervised classifica- clipping area: The regular or irregular area tion. The clusters are usually identified that will be processed and is defined by or labeled as some useful type of material drawn polygons or a region. (for example, an agricultural crop, a body clip art: Icons, symbols, and drawings dis- tissue type, or a soil type). It is impor- tributed in computer-readable format. tant to note that this raster does not con- Computer clip art was popularized by the tain values that can be subjected to fur- Apple Macintosh, which can use pub- ther mathematical analysis because the lished clip art for electronic cutting and clusters and their reidentification as ma- pasting into drawings or pages of text. terial or area types do not represent data TNTmips users can similarly create and values that are mathematically continu- share a variety of original symbols, pat- ous. For example, cells in a cluster arbi- terns, and line types. trarily assigned the value of 4 by the clustering process does not necessarily repre- clump: A set of contiguous line, node, and sent twice as much of something as a cell polygon elements in a vector object. assigned to a cluster that was given a value clustering: A process in which multiple, of 2.

page 13 Glossary for Geospatial Analysis

CMY or Cyan-Magenta-Yellow: The stan- objects defined by those points, can be dard set of subtractive, processing colors determined in 3D space within the inte- used in printing. Color printing devices rior of an object (for example rooms and use discrete dots of cyan, magenta and hallways in a building; adits, shafts, and yellow to present the appearance of a various tunnels in an underground mine; full-color image to the human eye. The locations in a timber stand; or areas in a combination of cyan, magenta and yel- hydro-geologic environment) and can be low produces black. However, some used to define interior surfaces in vector printers include black ink along with the applications and solid objects in vector above three colors, which is properly and CAD applications. CMYK called . color balancing: Adjusting the intensities CMYK or Cyan-Magenta-Yellow-Black: and distribution of red, green, and blue to See CMY or Cyan-Magenta-Yellow. create an image with a particular color CMYKcm: Used with six-color printers. appearance for display or printing. Cyan-Magenta-Yellow-Black-Light Cyan- color compression: Removing duplicate Light Magenta. (in some cases near-duplicate) colors codec: Short for compressor-decompressor. from a color map to make room for new The term applies to any technology used colors. for compressing and decompressing data. color depth or pixel depth: The number QuickTime Player and Windows Media of data bits each pixel represents. In 8- Player use codec technologies. bit contexts, the pixel depth is 8, and Codec can also stand for coder-decoder. each display pixel can be one of 256 In this context it refers to an analog to possible colors or shades of gray. With a digital and digital to analog converter that 24-bit raster (or with three coregistered converts real-world signals to digital form 8-bit rasters) the pixel depth is 24, and and back again. Codecs can be imple- 16,777,216 colors are possible. mented in software, hardware, or a com- color-infrared (CIR): Color-infrared im- bination of both. ages may be collected by an electronic coextensive: Covering the same ground area scanner or a camera that uses special film. exactly. If two raster objects are both Infrared film records the photographic coregistered and coextensive, there is a infrared radiation just beyond the range 1:1 cell correspondence for ground area of human vision as red. Normal red from coverage in each cell of the rasters. the scene becomes green, and green becomes blue. Normal blue in the scene is COGO: The Coordinate Geometry (COGO) usually filtered out and not recorded. process includes COGO commands that when executed accomplish meaningful Any physical or biological damage to functions for professional surveying and growing plants which begins to cause a civil engineering applications. COGO by deterioration in their vigor (their water definition is a command structured prob- and/or chlorophyll content) causes a lem oriented language and computer pro- rapid decrease in their reflectance of gram for the solution of geometric prob- photo-infrared radiation, and increases lems. COGO tools are useful for creating in their red reflectance. CIR photographs or editing vector or CAD objects with land show these changes much sooner and surveying, global positioning system, and more dramatically than normal photo- other precision data. The COGO ap- graphs or human eyesight. Healthy, proach has been used by surveying and green vegetation appears in bright red, civil engineers since approximately the while damaged, diseased, or dying veg- early 1960’s. COGO relates to the LOGO etation appears in shades of pink, tan, language used in early computing and per- and yellow. mits the creation of precise control and This knowledge was first used during the descriptive data entry into new or exist- Second World War when color-infrared ing objects tied to the ground surface, pro- film was called camouflage detection film. jection, and datum. COGO points and the It provided pre-visual detection of the

page 14 Glossary for Geospatial Analysis

changes in vegetation cut or damaged by log boxes, or separators. military activity and could very easily compose sequence: A sequence of two or separate color-camouflage materials (like more keystrokes used to create a single olive drab canvas) from live foliage. character, as in the case of European lan- color map or color table: A color map is guages that have characters with various the table, or map, used by a computer diacritical marks. system to assign display colors to digital composite color raster object: A raster values. A color map for an 8-bit raster object in which each cell contains a data object can contain a total of 256 colors. value representing one of the colors into A gray scale image may have a color map which all available color data for that cell with 256 shades of gray, ranging from has been compressed. For 8-bit raster black (0) to white (255). The first 64 objects, there are 256 possible colors for places in a color map are normally as- each cell; for 16-bit raster objects there signed to the “standard 64” annotation are 32,768. Composite color rasters are colors. Additionally, certain processes usually compressed from a red/green/blue may use 16 values for standard shades of raster set that retains a wider range of gray. The remaining 176 or 192 colors color information. The composite ras- are then available for the image colors ter still produces near photographic qual- used in the display. Some types of color ity color displays. maps that you will encounter in TNT- mips are optimized color maps and com- composite color video: The standard color posite color maps. video output of a VCR or video camera that adheres to the NTSC video standard. color palette editor: A TNTmips window All the color information is contained in which shows a table of the current dis- one signal (instead of in the three RGB play colors. With 8-bit data and devices, color signals). this palette includes 256 colors in 8 rows and 32 columns of color cells. computed field: A field in a database table with a value calculated from the values of color separation: Manipulating a full-color other fields in the same or different tables image in order to extract features of one of a single database. You define the ex- color or range of colors. The color sepa- pression used to generate the values for a ration process can be used to create a computed field using the same language binary raster object from a composite and syntax employed for database que- color raster object (or a set of three RGB ries. The appropriate record values for raster objects) to lift out blue line im- use in a computed field are determined ages, for example, leaving behind back- through primary and foreign key relation- ground colors and lines images of other ships or by element attachment. colors. Printers use related color separation techniques to prepare process color conflation: Determining a single resultant separates from full-color originals. line from coincident or nearly coincident lines while merging or editing vector ob- column: A vertical list of data values or jects. display cells in a raster object or display. conic projections: This group includes pro- command: A specific instruction to a com- jections that are constructed by placing a puter program entered by the user to per- cone tangent to the globe along a stan- form a desired action. dard parallel in the mid latitudes, or in the command prompt: Formerly called the case of a polyconic projection, placing a DOS prompt on PCs, it is a path that cone secant to two (or more) standard includes a drive letter followed by a : (co- parallels. Conic projections are com- lon) that ends in a > (greater than sym- monly used to depict hemispheres or bol) found in a command shell with each smaller portions of the earth’s surface. directory level separated by a slash. context: A file that describes how to recreate component: Any single element in a win- a web map that may be made up of many dow, including buttons, fields, scroll bars, different layers from many different Web sashes, panels, menus, panes, frames, dia- Map Services (WMSs).

page 15 Glossary for Geospatial Analysis continuous data: Data in a raster object is such as Stereo Modeling. In the manual said to be continuous if it can be repre- mosaic process, a control point is a fea- sented by a three-dimensional surface such ture in a piece of the mosaic (such as a that intermediate values can always be road intersection) for which the map co- derived with meaningful results. Example: ordinates are known. In the raster-to- an elevation raster has continuous data vector calibration process, a control because an elevation of 400 and an eleva- point is a feature that is co-located be- tion of 500 can fairly be averaged to as- tween the ungeoreferenced raster object, sign an intermediate elevation of 450. and the georeferenced vector object over- continuum: Continuous extents with no ob- lay. A control point may be something vious division into parts. like a bend in a river or a road intersection that shows on both a raster object contour map: A topographic map that uses and an overlying vector object. Tying contour lines to portray relief. Contour control points together lets TNTmips lines join points of equal elevation. adjust scale, orientation and geometric contours: Lines on a contour map or other distortion between rasters and vectors. isomorphic map that identify levels of a TNTmips’ georeferencing and registra- parameter at specified, discrete intervals. tion processes rely on control points in- contrast: The difference between bright and troduced and identified on the display dark values in the display or printout of a with the mouse. (See also: tie points) continuous tone (usually grayscale) im- control point list: One type of map regis- age. The stronger the contrast, the more tration subobject (Regist) that contains difference between the brightest and dark- a paired list of map coordinates and cell est values. Most images benefit from a coordinates. TNTmips uses the control process of contrast enhancement, which point information to derive map cali- artificially increases the contrast. bration for the entire object. (See also: TNTmips provides different methods of linear transform) distributing intermediate display or print controls window: The TNTmips display values. The Linear contrast model as- and edit processes always include at least signs straight-line increments of inten- two windows: the controls window and sity. Many images look better when they one or more view windows. A single con- are produced with the Normalized controls window can govern multiple view trast model, which assigns intensity in- windows. crements according to a normal distribution curve. convolution: Mathematically determining the data value for a new cell in an m x n contrast table: A contrast table assigns dis- neighborhood of cells. Raster filtering, play intensity values to raster object cell resampling, and other raster processes values using a specified translation use convolution. Convolution processes method, such as linear or normalized should never be applied to raster objects translation. The type of translation cho- that contain categorical data. Convolu- sen and the limits defined will change the tion is only appropriate for continuous display values but, in general, the result is data. to increase the apparent differences between the majority of cell values, which co-occurrence raster: A raster created in usually fall within a narrow range. the Color Binarization process. The cell values in the co-occurrence raster are the control panel or panel: An area of a win- frequencies of occurrence of the same dow that holds related buttons, sliders, cell value in adjacent cells in the input fields, and other components used to gov- raster object. The Color Binarization ern the behavior of a process. process analyzes groups of eight neigh- control point: Points, elevations, and/or cells boring cells in the input raster object to which are used to establish map coordi- determine the occurrence of the same nate control for ungeoreferenced objects cell value within the group of cells. or objects that are to be used in a process

page 16 Glossary for Geospatial Analysis coordinate: A set of numbers that designate computing engine of a computer. position in a given reference system, such CRS: Coordinate Reference System. as X-Y in a 2D coordinate system and X- Y-Z in a 3D system. CRT: Cathode ray tube. coordinate system: A reference system for cross validation: An option in the Kriging defining precise locations on the earth’s method of Surface Fitting in the Surface surface. Coordinate systems may be in- Modeling process. This option is a pre- dependent of or tied to a particular map processing function that calculates the projection. mean error and standard deviation for es- timated control points compared to the coprocessor: Older microcomputers used actual control points. for heavy computational tasks had a second microprocessor, called a math cubic convolution or cubic interpolation: coprocessor. To speed things up, the main A computationally intense interpolation CPU assigned its tedious arithmetic to method used in raster resampling. This this helpful specialist in much the same method determines a new cell value to way that modern accountants use calcu- produce a smoother result by fitting a lators for the computations their grand- cubic polynomial surface to a 4 x 4 neigh- fathers did by hand. In the Intel CPU borhood of cells. Bilinear interpolation series, the main processor’s chip number normally produces results which are al- ended with the digit 6 and the most as good. Cubic convolution should coprocessor’s chip number is the same not be applied where the mean data value except for the final digit 7: 80286 / for a group of cells is undefined as in cat- 80287; 80386 / 80387. Since the 80486, egorical data (like an 8-bit color raster Intel has included the math coprocessor object, a classification map, or any raster in the basic design. (Thus there was no object containing similar category-type 80487). data). coregistration: The condition in which as- cursor: See: mouse cursor, text cursor. sociated raster and/or vector objects over- cursor hot spot: The pixel location on a lay each other with correct orientation cursor shape at which the cursor activity and geometry so that corresponding in- takes place. For example, the hot spot ternal features align. on an arrow cursor is at the point of the correlation: The degree of relatedness be- arrow, while the hot spot for a cross-hair tween two objects; more specifically, the cursor is at the intersection of the degree to which one value in a set of crosshairs. values can be used to predict the corre- cylindrical projections: This group of pro- sponding value in another set of values. jections includes all projections con- correlation points: (also called tie points). structed by placing a cylinder tangent to A pair of points collocated on a com- the globe along a standard parallel—usu- mon feature, such as a road intersection, ally the equator, or secant to the same in a pair of images. A set of correlation standard parallels in opposite hemispheres, points defines the mutual spatial rela- respectively. tionship of a pair of overlapping images Cyrillic: An alphabet widely applied to the without regard for their real position in a Slavic languages, as in the case of the map coordinate system. thirty-three-letter Russian alphabet. Since cost raster: A cost raster is a raster object the 1930’s it has been used for most of with cell values that represent a price the languages of the former Soviet Union. per distance unit; for example, monetary (Attributed to Saint Cyril, a ninth-cen- expenditure per meter, fuel usage per tury Christian apostle of the Slavs.) mile, traversal time per mile, and so forth. coverage file: See: pcARC/INFO coverage file. CPU: Central Processing Unit. The main

page 17 Glossary for Geospatial Analysis

store attribute values for an individual example in one or more fields. (See also: external database, field, foreign key, in- — D — ternal database, primary key, record, table.) dangling line: A dangling line element in- database query: The database tables at- tersects another line element on only one tached to vector/CAD objects can be que- end. The unattached end terminates in a ried to reveal those elements that meet node element that is not shared by an- the criteria specified in the query and other line element. Dangling lines may drawing styles can be assigned in accor- be either overshoots or undershoots. dance with query results. Database query Dangling lines can be avoided by using can be used to select vector/CAD ele- the snap options when editing. ments for display and assign their drawing styles. database form: A database form allows you to reorganize the information in a table data mask: A processing barrier that only for display in single record view. This allows data values in a chosen range to reorganization may include changing the pass. You might choose a data mask to order and placement of fields and / or dis- block all values outside a selected color playing only selected fields from an ex- range, eliminating all image features existing database table. You can also modify cept those of the color you want to use field titles to include spaces, which are in a process. You can also use a mask to not allowed in actual field names, to ex- select a processing area from a larger ceed the 15 character maximum, or you scene. The mask blocks off the parts can change the name entirely if the origi- that you want to exclude from the cur- nal seems too cryptic for the intended rent analysis. audience. You can also add text that is DataTip: A DataTip contains a raster cell not associated with a particular field to value or element information for vec- provide logical groupings for the infor- tor, CAD, shape, or TIN objects. For all mation presented in the form. A database objects except raster objects, you can des- form cannot exist without an accompa- ignate the database table and field for use nying database table. Editing in the de- as a DataTip. Place the cursor over the fault table layout or in any of the forms cell or element for which you want to created as an alternate means of viewing see a DataTip and wait briefly. DataTips the same information alters the single set operate in a manner similar to ToolTips. of values used in all cases. Database forms In TNTmips, a virtual field can be used are stored as subobjects of the database. to produce a multiline DataTip. Such database object or dBASE object: A data- DataTips present information from mul- base is a collection of information re- tiple fields in one or more database tables. lated by some unifying theme, such as de- datum: A mathematical description of a mographics, epidemiology, or geographic smooth surface that closely fits the mean location. There are a number of popular sea-level surface for an area of interest, database programs, such as dBASE IV, that which provides an imaginary, perfectly assist in the retrieval and management of flat horizontal surface for use as a map such information in electronic form. The base with x,y coordinate measurements. TNT products also handle databases and A datum is derived from a chosen ellip- use specific terminology for the compo- soid, and provides the surface to which a nents that comprise a database. A data- cartographer refers ground control mea- base in the TNT products can be a main surements. Maps of large extent must level object or a subobject of a raster, vec- use consistent parameters for ellipsoid tor, CAD, or TIN object. The object gen- and datum to insure consistency between erally defines the “unifying theme” (for the map projection and ground control. example, the soil type polygons for the (Map Projections Used by the U. S. Geo- Crow Butte area). A database is organized logical Survey, Geological Survey Bulle- into tables, which contain records that tin 1532, Second Edition, U. S. Govern-

page 18 Glossary for Geospatial Analysis

ment Printing Office, Washington, D.C., ject will not usually default to an existing 1982, pp. 13-15). (See also: ellipsoid.) object to avoid accidentally overwriting daughter object: A completely indepen- it. Well thought out defaults are one of dent project file object that may be the simplest and most easily incorporated treated by TNTmips as subordinately re- forms of artificial intelligence that can lated to some other object. For example, exist in a system. objects attached by HyperIndex® to degree or °: A unit of measurement equal to some other object are called its daugh- 1/360 of a circle. A degree of latitude on ters and the object used for the primary the earth’s surface is about 69 miles. A index layer is called the parent. (See degree of longitude is about 69 miles at also: HyperIndex, index area, parent ob- the equator and undefined at the poles, ject, stack) but any point on the surface rotates decibel rasters: Radar images in which the through a degree of longitude in about 4 raster cell values are presented as log scale minutes of time. (See also: arcsecond, values based on the power of 2. Users minute.) can choose to generate decibel raster ob- Delaunay criterion: A condition jects in addition to raster objects with that must be met when a TNTmips TIN linear cell values when they import JPL object is computed. The technique used AIRSAR and TOPSAR radar formats. to generate the TIN object, known as decision rule: The criterion used to assign Delaunay triangulation, produces a set of cells to a prototype feature in TNTmips triangles that are as equi-angular as pos- feature mapping. Cells in the image are sible. All circumcircles of Delaunay tri- tested against the decision rule, and those angles contain no points other than the that match are highlighted as prototypes. three that define the triangle and its cir- You select the desired decision rule when cumference. Satisfying the Delaunay cri- setting up the raster objects to be ana- terion ensures that any point on the sur- lyzed by feature mapping. A simple deci- face is as close as possible to one of the sion rule would be to compare the three nodes, the number of long skinny triangles color values of each cell on the display is minimized, each sample point is con- to three color values known to occur in nected with two nearest neighbors to form the target feature. a triangle, the triangulation solution is unique and independent of the order in DCW: Digital Chart of the World was the which the points are processed, and the first digital 1:1,000,000 map of the world solution produced allows easy generation in VPF format. This data can be down- of Voronoi diagrams (Thiessen polygons) loaded from the NGA website. This origi- for the same set of input points. Voronoi nal product has been replaced by the diagrams are widely used in spatial analy- more detailed VMap0 and VMap1 data sis. sets, which are also available for download from NGA. DEM: Digital Elevation Model. (Also DTM, “Digital Terrain Model”). A computer- defaults: The start-up settings for a system ized representation of an elevation sur- or an individual process. In TNTmips face. Specifically, a raster in which the the defaults are usually automatically set value in each cell represents the surface to be the most probable value desired if elevation at that location in the scene. the process is to be repeated either im- DEMs are USGS geographic elevation data mediately or at some indefinite future distributed in raster form on open reel date. Many TNTmips defaults are set to magnetic tapes. There are 2 basic types: the last value, raster object, position, or 1) The DMA type created by the Defense other parameter used. Some defaults are Mapping Agency in both a fixed cell size always reset to a selected condition, re- and a 3 x 3 arcsecond cell size distributed gardless of the last choice, in order to in 1 x 1 degree files. 2) A newer format prevent inadvertent destruction of valu- for those 7.5' USGS quadrangles that have able results and data sets. For example, been processed into 1 x 1 arcsecond el- the location of a new output raster ob-

page 19 Glossary for Geospatial Analysis

evation cells. procedures look and work the same way demand: The number of something that uses across a variety of hardware configura- a center in network analysis; for example, tions. the number of students living along a road DGIS: Direct Graphics Interface Standard. places a demand on a school (a center). diacritic: An accent mark added to a char- Demand values are necessary before ca- acter to distinguish it in pronunciation pacity limits can be meaningful. or meaning from other uses of the same dendrogram: A tree diagram whose branches character. Common diacritics, for ex- depict a hierarchical classification struc- ample, distinguish several versions of the ture, showing the degree of relatedness of Latin character “a:” á, à, â, ä, ã, and å. different classes. dialog box: A type of subwindow that opens densification: Densification of vector lines to display a message, warning, process- adds vertices to a line to enforce a par- ing message or application components ticular shape generated by splining. TIN that require the user’s input. The user densification is the process of adding must typically make some kind of deci- nodes to a TIN object based on some cri- sion and exit the dialog box before con- terion, such as highest deviation from a tinuing with the process by pressing a planar surface in an underlying DEM or button such as OK, Cancel, or Skip. correlation between a stereo pair of diapir: An upfolded geologic structure, such DEMs. (See also: TIN densification.) as an anticline, in which mobile, plastic depression: (watershed analysis) A depres- core material has broken through or sion exists when the lowest elevation value pierced the more brittle overlying rock. within the watershed is lower than the digital: Information stored and processed lowest value of the cells that form the with numerical digits, often in base 2. watershed boundary. Drainage is inward Digital information processing is con- from the inside perimeter of the depres- strained by the finite set of numbers a sion toward the lowest point. system uses, such that every data value is depressionless raster: An elevation raster forced into its nearest representation. created from the original elevation raster For example, a digital clock may only with all depressions filled. Such depres- show hours, minutes and seconds, but not sions are filled by assigning increased el- fractions of a second. At some point, evation values until a flow direction can every digital system faces the same kind be established without going uphill. The of limit in accuracy. On the other hand, depressionless raster is attained when the digital information is easy to copy, store, number of depressions is reduced to zero. manipulate and reproduce dependably. destripe: Procedure that removes system- (See also: analog.) atic striping within an image. This strip- Digital Elevation Model: See DEM. ing typically occurs in an image gener- Digital Terrain Model: See DEM. ated by a multispectral scanner that sweeps multiple scan lines simultaneously. digitize: Convert analog data into a digital form; also, more specifically, use an X-Y developable surface: A geometric form ca- digitizing tablet to convert data to digi- pable of being flattened without stretch- tal form. ing or tearing, such as cylinder or a cone (both of which can be cut and laid out digitizer: A device that converts an analog flat), and a plane (which is already a flat signal or representation to a digital one. surface). (See also: scanner, video digitizing board, X-Y digitizer.) device independent: Not constrained by idiosyncrasies of hardware environment. digraphia: Use of two different scripts for All processes in TNTmips function inde- the same language, such as Latin and pendently of the physical input, output, Cyrillic for Serbo-Croatian, Devanagari and display devices. Device independent and Arabic for Hindi-Urdu, and Pinyin software is also designed so that all of its and characters for Chinese.

page 20 Glossary for Geospatial Analysis dimensionality: The number of directory. coregistered images in a project file for discrete values: Cell values of rasters that one site. An image contained in one represent discrete data, such as categori- color composite raster has a dimension- cal data, for which interpolated values ality of one. An image contained in a have no meaning. three-raster RGB set has a dimensionality of three. A Landsat TM image map disk drive: A mechanical component of a for a single date will have a dimensional- computer that allows data to be read from ity of up to seven. or written to a spinning magnetic or optical disk. If elevation rasters, panchromatic rasters, and multi-date airphotos are added displacement: The difference between the to the project file, the user will likely apparent x,y position of a feature in a want to reduce the dimensionality of the raw photo and the feature’s true position. image to simplify analysis and manipu- Displacement is caused by camera char- lation. (See also: dimensional reduction) acteristics, tilt, nearness to the target scene, and variations in the elevation of dimensional reduction: Reducing the the target terrain. number of coregistered rasters in a project file to speed up their analysis. TNT- display: Display is used loosely to mean a mips’ dimensional reduction techniques monitor or what is drawn on it, but in the include principal components and Kauth’s context of the TNT Display process, a Tasseled Cap. display is a layout or group that is independent of other layouts or groups in the dimmed selection: A menu selection that process. A display consists of a list of is not currently available as indicated by layers in the Display Manager window and its grayed-out appearance. one or more View windows that show the directly attached: The relationship of an selected layers. attribute table to elements when the table display board or display card: An elec- attachment type is anything other than tronic circuit board installed in a micro- Related Only. Directly attached table computer that translates the computer’s types include implied one-to-one (not display data into signals for the monitor. available for CAD), one record per element, one to one, and no restriction. display group: A standalone grouping of layers for the purpose of display (may also directly linked: Directly linked files are be a single layer). Groups can be com- files that can be read directly by the TNT bined in display and page layouts. products without using the import process to establish the link. Examples of display histogram: A graph showing the file types supported for direct linking, or number of times a data value occurs in a direct use, are JPEG2000, MrSID, raster display plotted against the range of shapefiles, and DWG. For more infor- possible values. For any RGB color the mation see the Quick Guide entitled Di- user selects, the TNTmips display histo- rect Use of Popular Geodata Formats. gram shows how may cells there are in the display for each intensity level of that directory or sub-directory: In DOS, color. Linux, and UNIX, a directory is a logical, user-defined division of a storage display layout: One or more groups arranged device. For example, a user may divide a specifically for onscreen purposes. Can hard disk into several directories, with be converted to a page, or hardcopy, lay- each directory used to store files that out for printing. pertain to a certain task. One directory Display Manager: The window in the Dis- may contain programs and documents play process that lists all the layers in all for word processing, another for spread- the open displays. It provides the means sheet analysis, and another for database to open new or existing groups and lay- manipulation. Newer operating systems outs and to manage their contents. use the word folder synonomously with display monitor or display screen: (historical term) One of the two screens in

page 21 Glossary for Geospatial Analysis

the old DOS MIPS system (v3.3 and ear- dpi: Dots Per Inch. A measure of scanner, lier). The display monitor showed the screen, and printing resolution. The more image and worked with the mouse. The dots per inch, the more detail a device other screen was the text monitor, which can process for a given area of page or worked with the keyboard and displayed display. On the other hand, the more menus and system information. dots per inch, the higher the demands on machine storage and processing (files get dissolve: The removal of boundaries between large and processing slows down). polygons that have one or more specified attribute values in common. drag: To press and hold a mouse button while moving the mouse. distance raster: An output raster created by certain classification methods which drag bar: A window’s title bar. records the Euclidean distance between drape object: An object that takes its three- each cell and its assigned class center. Dis- dimensional shape from a surface object tances are represented as 32-bit floating that is lower in the layer list. Any object point numbers. High distance values may type that is usable in TNTmips can be identify cells which were not adequately used as a drape object. classified using the chosen method and drawing order: The order in which layers input parameters. are drawn during display. The object that dither pattern or dithering: An image pro- is first in the drawing order will appear to cessing technique that creates the visual be on the bottom when all layers are dis- illusion of continuous tones when an im- played. The order of objects in the layer age is printed. The illusion of shading is list reflects the displayed appearance for obtained by the calculated placement of a group with the background always at picture elements that usually can not be the bottom of the list. resolved by the human eye. The calcu- drawing style: The style used to render a lated placement of the picture elements screen or hardcopy representation of a is called the dither pattern and creates vector or CAD element. The drawing more colors and shades of color than style for point features includes size and would be printed otherwise on printers whether unfilled, filled, or represented with fixed intensity, fixed size printels. by a symbol. The drawing style for line dithered raster: A printer-ready 4-bit ras- elements includes line width and whether ter object in which each cell corresponds drawn in solid color or using a line pat- to one dot (printel) on the hardcopy out- tern. The drawing style for polygon ele- put from the printer. ments includes the border color and DLG: Digital Line Graph. A USGS map for- whether or not a polygon is filled. Your mat usually used to distribute topographic choice of single color filling or use of a maps in vector form. transparent fill pattern and whether to draw the border if filled are also part of DMA: 1) Defense Mapping Agency of the the drawing style. US Department of Defense. 2) Direct Memory Access. driver: A set of computer commands that control some input or output process for double precision: A high level of accuracy a particular type of hardware. Drivers based on the possible number of signifi- translate general program features into cant digits that can be stored for each the specific communication protocol re- coordinate or raster cell value. quired by a particular device, such as a DOS:Disk Operating System. DOS for per- particular printer. sonal computers was developed and mar- dropout: A missing piece of an image, or keted by IBM and Microsoft from 1981 more generally, of a data stream. Drop- to 1994. It provided management utili- outs can be caused by the improper use ties for the files and other resources of or function of a hardware device, by sig- the microcomputer. A DOS, or command, nal interference or disruption, or by other shell can still be accessed from Microsoft problems. A dropout in text transmis- Windows.

page 22 Glossary for Geospatial Analysis

sion causes missing letters or words. A definition of eigenvalue is: a scalar for dropout in scanning can cause gaps in which there exists a non-zero vector such the image of a line. Scanning a fine line that the scalar times the vector equals at too low a resolution or with too low a the value of the vector under a given lin- binary threshold is likely to cause drop- ear transformation. outs in the resulting raster image of the eigenvectors: Used in Principal Components line. calculations and the Hyperspectral Analy- DTM: Digital Terrain Model. Elevation data sis process, eigenvectors have value and in a 3 x 3 arcsecond grid form or a simi- direction. Eigenvectors are a mathemati- lar rectilinear form created by the De- cal rather than statistical entity. fense Mapping Agency. EISA: Extended Industry Standard Architec- DVD: Digital Versatile Disc. A 5" optical ture. One of the standard bus architec- disc for video or data with greater stor- tures for microcomputers. (See also: bus.) age capacity than a CD-ROM (currently ELAS: A public domain, first-generation mini- 4.7 Gb). and microcomputer image processing sys- DXF: Data Exchange Format for storing vec- tem developed by NASA at the Stennis tor or CAD data in ASCII or binary files, Space Center in Slidell, LA. which can be used to interchange elastic box: A rectangle displayed by TNT- AutoCAD files with other CAD software. mips which can be moved or resized with the mouse. Elastic boxes are used to select areas on the display monitor in processes like measuring and drawing. — E — elastic circle: A circle displayed by TNT- mips which can be moved or resized with easting: A rectangular (x,y) coordinate mea- the mouse. Elastic circles are used to se- surement of distance east from a north- lect circular areas on the display monitor south reference line, usually a meridian in processes like measuring and drawing. used as the axis of origin within a map elastic line: A line displayed by TNTmips zone or projection. False easting is an which can be moved or resized with the adjustment constant added to coordinate mouse. Elastic lines are used to draw seg- values to eliminate negative numbers. ments on the display monitor in processes edge conditions: In agricultural row crop like measuring and drawing. imagery, the biomass values for cells in electromagnetic spectrum: “The entire the middle of a healthy row are high, spectrum, considered as a continuum, of while the thin plant fringes or bare soil all kinds of electric, magnetic, and visible between rows have low biomass values. radiation, from gamma rays having a Low biomass values along the edges of wavelength of 0.001 angstrom to long healthy rows are normal and are no cause waves having a wavelength of more than for concern. But edges cannot be distin- 1 million km” (Random House). Re- guished by value alone from the low bio- mote sensing devices typically record elec- mass values of regions of insect or dis- tromagnetic bands in the region of opti- ease damage which must be identified and cal light and may include the near infra- given special attention. red. (See also: spectral band) EGA: Enhanced Graphics Adapter. An early electronic atlas: A HyperIndex created from graphics subsystem capable of 64 colors maps, photos and airphotos, airvideo, and that was widely used in DOS-based mi- database links. The electronic equivalent crocomputers. The EGA was developed of a printed atlas. in 1984 to solve the poor resolution and element: (CAD) Any defined shape in a CAD limited color selections of the CGA. object. These include arc, arc wedge, arc elgenvalues: Values used in the chord, box, circle, elliptical arc wedge, Hyperspectral Analysis and Principal elliptical arc chord, ellipse, elliptical arc, Components processes. The dictionary line, point, polygon, and text elements.

page 23 Glossary for Geospatial Analysis

A block inserted into another block also NASA-sponsored mission. acts as an element at its insertion site. epidemiology: The study of the various Unlike vector elements, individual CAD factors influencing the occurrence, dis- elements retain their original shape re- tribution, prevention, and control of dis- gardless of what other elements are added ease, injury, and other health related and where they are placed. events in a defined human population. element: (vector) A vector object is made up epipolar:A condition of geometric copla- of three different types of elements: 1) narity established between a pair of ste- points, which are single coordinate pairs reo images to give them the same rela- (or triplets) that define a point (such as a tive orientation. Stereo images that have well); 2) lines, which are curvilinear epipolar orientation can be used to de- strings of coordinates which define a rive a network of correlation points in curved line (such as a stream) and which preparation for DEM extraction. have nodes at the ends and intersections of lines; and, 3) polygons, which are col- EPPL7: Environmental Planning and Pro- lections of lines which inscribe an area gramming Language. A raster-based GIS (such as a lake). system developed and sold by the State of Minnesota. ellipsoid: An ellipse rotated about its shorter axis. In the context of map projections, EPS: Encapsulated PostScript. an ellipsoid is a geometric reference sur- EPSG: European Petroleum Survey Group. face that closely approximates the geoid. equalized histogram: A histogram whose Since the geoid (that depicts the earth) is distribution has been mathematically ad- an irregular spheroid characterized by justed so as to come as close as possible polar flattening (or ellipticity), many to having an equal number of cells of methods have been developed to describe each data value. its ellipsoidal deviations. Cartographers have a selection of ellipsoids from which equator: The great circle that is equidistant to choose; most of which have “best-fit” from each of the earth’s poles and di- properties for certain portions of the vides the earth into northern and south- globe. In 1924, an International ellipsoid ern hemispheres. Latitude is measured was defined which described the earth el- with reference to the equator. lipsoid as a flattening of 1 part in 297. erasable optical cartridge or EO car- Historically, ellipsoids were derived from tridge: A two-sided removable storage careful surface measurements. More re- unit that typically holds between 300 and cently, satellite data has been used to con- 500 megabytes per side. Data on EO struct ellipsoid models that relate coordi- cartridges can be erased so the cartridge nate measurements to the earth’s center can be updated or re-used. of mass. A few common standards: GRS erasable optical drive or EO drive: A 5 1/ 1980 (North America), WGS 72 (NASA/ 4" high capacity storage device that uses satellite), Australian (Australia), removable double-sided cartridges which Krasovsky (Soviet Union), Clarke-1880 typically store between 300 and 500 (Africa), Clarke-1886 (North America, megabytes per side. EO drives are simi- Philippines), Airy (Great Britain), Bessel lar to WORM drives, with the difference (Central Europe, Chile, Indonesia), that EO cartridges can be erased and re- Everest (India, Burma, Pakistan, Afghan, used, while data on WORM disks is per- Thailand, and other southern Asian coun- manent and cannot be erased. (See also: tries), and International (most other ar- WORM drive.) eas). ERDAS: Earth Resources Data Analysis Sys- EO cartridge: See: erasable optical cartridge. tem. A raster-oriented microcomputer EO drive: See: erasable optical drive. image processing and GIS system by Leica EOS: The Earth Observation Satellite used Geosystems. to study the earth as a system while track- escape code: A code which controls the ing long-term, global changes. EOS is a format of text output. SML supports a

page 24 Glossary for Geospatial Analysis

set of common escape codes: \t (tab), \b sion is true only if the value of numlines (backspace), \n (newline), \ (line continuation: the “stitch” can evaluate to a number (for example: character), and \\ (the ‘\’ character). 2*YIELD). If such an expression is used ESRI: Environmental Systems Research In- where true and false values are needed, 0 stitute headquartered in Redlands, CA. is treated as false, and anything else is treated as true. Ethernet: Ethernet is a local area network that uses a bus topology for reliable high extents: The geographic extent of data speci- speed communications in a limited geo- fied by the minimum bounding rectangle. graphic area, such as an office of univer- external database file: A database file that sity complex. has been linked to a project file and is euclidean distance: The shortest distance maintained as a separate file. An exter- between two points in feature space, cal- nal database file may still be processed by culated using the Pythagorean theorem. your database programs. (See also: database object, internal database file.) exabyte, Ebyte, or EB: A computer unit of measurement for 260 (approximately) external program: A program that is not 1,000,000,000,000,000,000 bytes, part of TNTmips. It may be commer- 1,000,000,000,000,000 kilobytes, cially produced or written by you. 1,000,000,000,000 megabytes, external raster: A raster file that has only 1,000,000,000 gigabytes, 1,000,000 been linked to a project file and is being terabytes, or 1000 petabytes. (See also: maintained as a separate file. An exter- bit, byte, gigabyte, kilobyte, megabyte, nal raster 1) is stored in a DOS file, 2) petabyte, terabyte, yottabyte, zettabyte) follows a very simple format, and 3) is expansion slot: A socket for an optional not stored internally in a project file. To circuit card on the main circuit board of all TNTmips processes, this object still a microcomputer (the motherboard). appears to be a part of a project file. How- explicit destruction: When a user action ever, external programs can modify it. has irreversible or negative conse- extrema points: The highest and lowest quences, the process requires the user to points and flat areas locally as indicated take explicit action and to confirm that by the elevation raster cell values. Ex- intent by responding to an appropriate trema are change points determined by warning message, such as “Are you sure the comparison of each cell to the eight you want to delete selected items?” be- adjacent cells. A cell whose eight bound- fore destruction is performed. ary cells are all lower than the cell is de- exporting vector or raster objects: Ex- fined as a single local maximum. A cell porting an object from a TNTmips whose eight boundary cells are all higher project file converts it to a format rec- than the cell is defined as a single local ognized by other image processing or GIS minimum. Two or more adjacent cells software. Color schemes; arc, node, and with the same value whose boundary cells polygon structure; geographic calibra- are all lower are defined as contiguous lo- tion; and any other supporting data used cal maxima. Two or more adjacent cells in the target format is included. The with the same value whose boundary cells completeness of the conversion is only are all higher are defined as contiguous limited by the extent to which local minima. Two or more adjacent cells MicroImages can decode the format from with the same value whose boundary cells the developer’s information or determine also have the same value are defined as a it from sample files. flat area. expression: A line in a query or script that compares values. An expression evaluates to “true” (1) or “false” (0). Ex- ample: numlines < 3. It compares the numlines variable for the current node element with the number 3. The expres-

page 25 Glossary for Geospatial Analysis

most of the classification automatically when working with high-quality materials like satellite multispectral images. — F — With more input from the user, the process may also successfully map features in images created from 35mm slides or false easting: An adjustment constant added noisy airvideo. to easting coordinate values to eliminate negative numbers. (See also: easting.) feature space: The theoretical n-dimensional space occupied by n input raster false northing: An adjustment constant objects. Each raster object represents added to northing coordinate values to one dimension, and its cell values repre- eliminate negative numbers. (See also: sent positions along one of the orthogo- northing.) nal coordinate axes in feature space. The far range: The region farthest from the set of raster values belonging to a cell aircraft in an image created by a synthetic define a vector in feature space. aperture radar (SAR) sensor. feature type: The identity of a feature sup- FFT or Fast Fourier Transform: one of the plied by a TNTmips user. procedures in raster filters. See also: Fou- fiducial marks: (photogrammetry) In- rier Transform. dex marks, usually four, which are rigidly feathering: One of the options available connected with the camera body and for handling cell values in the overlap- which form images on the film negative ping portions of the input objects in the and usually define the principal point of Mosaic process. Two types of Feathering the photograph. methods are available: Linear and Non- field: (database) One component in a data- linear. Each type uses a weighted average base record. Fields report values (either of corresponding input cells. The qualitative or quantitative) for the indi- weighted average varies with distance vidual represented by that record. For from the image boundaries. The weight- example, a database record in a table con- ing coefficients for each image are zero cerned with agricultural potential may at the boundary and increase inward to contain fields that provide qualitative 1.0 at the feathering distance from the evaluations of a ground areas’ produc- edge (feathering distance is specified by tion potential for grain, legumes, or trees, the user). while a database record in a table of poly- feature: An area in an image that you locate gon statistics may contain fields that re- and map in the TNTmips feature map- port quantitative information such as the ping process. A feature is a continuous polygon’s area, boundary length, and cen- area (it may have holes in it) that does troid coordinates. (See also: database ob- not touch any other area of the same ject, record, table.) type. (When two features of the same field: (video) Background: The image you type touch, they immediately become a see on a TV screen is composed of a set single larger feature.) Features may rep- of about 480 horizontal lines. The lines resent anything the user chooses to iso- are projected in two passes of the signal late and identify, like ponds, lakes, agri- beam. Each pass only projects every cultural fields, a biological entity in an other line of the image: the odd lines in NMR scan, or bones in a CAT scan. one pass, and the even lines in the next feature class: The identity of a feature sup- pass. One scan takes 1/60 of a second, plied by a TNTmips user. A class is a set so the whole picture (the frame) is re- of all features of the same material. A freshed every 1/30th of a second. class is named to identify the kind of A field contains every other line of the material it contains (for instance “corn”). complete video image. The primary field feature mapping: A TNTmips process for contains the odd lines; the secondary field isolating, identifying, and typing areas in contains the even lines. multivariable images. TNTmips can do

page 26 Glossary for Geospatial Analysis field: (window) An area of a window that + 3-digit county FIPS code or TGR31109 allows keyboard entry of text. for Lancaster County, Nebraska. field of view: Area visible from a viewers flat: A raster cell that has the same cell value location. In the Viewshed process you as its eight neighbor cells. Calculated from can adjust the position of the viewpoint an elevation raster object, a raster object location in relation to the vertical plane of flats provides a representation of lo- of the surface object. cations with poorly defined drainage. figure-ground separation: Separation of flat tileset: A flat tileset is one that has no the foreground (figure) from the back- directory hierarchy. All the tiles are ground (ground) in an image. placed in a single directory that might file: A stored collection of related material contain millions of tiles required to cover (programs and data) analogous to a the area of the source images or maps for physical file folder that is used to store a all the zoom levels available. The nam- collection of papers on a particular sub- ing structure of each tile defines where it ject. occurs on the ground (i.e. its georeference) and its zoom level or scale. file format: A particular, pre-described layout pattern for data in a computer file so Operating systems have limits on the it may be used or acted upon by a pro- number of files that can be in a directory. gram. A TNT project file has a complex Vista and Windows 7 limit a FAT32 direc- format recognized only by the TNT fam- tory to 65,536 files. ily of products and by user programs de- flight path: The path taken by aircraft, sat- signed and built with the TNTmips li- ellite or other imaging sensor platform. brary. Similarly, a commercial database The flight path controls the nadir as well system uses only database files that fol- as the area imaged. low its particular file format. floppy disks, floppies, diskettes, or flex- fill color: A solid color used to fill a closed ible disks: A thin, flexible magnetic disk shaped in a vector or CAD object or an for computer program and data files. area defined by specified boundary col- Floppies are inserted into a computer’s ors in a raster object. floppy disk drive much like a cassette tape fill pattern: The drawing pattern for the is loaded into a tape player. Floppy disks interior of a polygon for display or print- come in different sizes and capacities, and ing. TNTmips lets you create and assign must be used in the right kind of drive and fill patterns for raster (paint), vector, computer. Floppies are slower and hold and CAD operations. A fill pattern can less data than a hard disk. (See also: hard be as simple as a solid color, or as de- disk, RAM disk.) tailed as a repeated image of a duck or flow accumulation: In a raster-based analy- tree. Soil types can be represented by sis, the total number of cells, including traditional color cross-hatching. Fill non-neighboring cells, that drain into a patterns can be designed from the 64 stan- selected cell. dard colors plus transparent (so the un- flow direction: In a raster-based watershed derlying image shows through). analysis, each cell is assumed to drain into film recorder: An output device that works one of its eight neighbors (left, right, up, like a printer but produces slides or prints, down, plus the four diagonals). The flow usually on 35mm film. direction of a cell is expressed in degrees: filtering: Clarifying detail, sharpening con- up=0, right=90, down=180, left=270; and trast, smoothing edges, and otherwise en- the diagonals: 45, 135, 225, 315. hancing image quality. flow path: The drainage path through a wa- FIPS code: Federal Information Processing tershed that begins at any selected point Standards code that identifies each state (called the flow path “seed”) and runs to (2 digits) and county (3 digits). TIGER one of the outlets of the study site. files are named by incorporating FIPS flow path raster: A raster that indicates the codes, e.g. TGR + 2-digit state FIPS code

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flow path from one or more seed points the same database. A foreign key con- to one of the outlets of the study site. sists of one or more attributes that can flow path seed point: (watershed analysis) uniquely identify a record in the table Any point selected to be the origin or containing the primary key. The identi- highest point in a flow, or drainage, path. fication and designation of foreign keys are automatic. (See also: database, field, focal length: The distance from the lens at primary key.) which parallel light rays are focused to a point. Focal length is essentially a mea- form: See database form. sure of the “zoom” level of a camera lens. format: The preparation of optical, floppy, Longer focal lengths create a higher zoom or hard disk media; a tape cartridge; or level, capture a smaller area of the target other storage media with basic locational scene, and introduce smaller displacement information so that the media can be errors. 6-inch, 8.25-inch, and 12-inch used. Some manufacturers provide focal lengths are common for aerial pho- preformatted media for their specific de- tography done by government surveying vices, such as hard drives. Other generic authorities in the United States. Focal media, such as floppy disks, are usually length affects the geometry of the photo not formatted when purchased. Some and must be provided as an input to com- media, usually those with a serial record- putational orthoimage and DEM pro- ing format, such as open reel tape, are cesses. automatically formatted as they are used. focus: Focus is generally thought of as a pho- Fourier transform: A type of two-way fre- tographic term, such that when things are quency transform for identifying and re- in focus, they are not blurry. In software, moving unwanted spatial frequency com- however, many actions are defined by ponents in an image. The Fourier pro- which window, field, or item has focus. cess is normally used to identify and re- Focus may be indicated by highlight or move systematic noise “spikes,” such as text cursor position, and is generally ac- regular lines that may have been intro- quired by a mouse click. Focus is some- duced by a faulty image collection de- times moved from one field to the next vice. The process works as a two-way using the key. operation. First the forward transform folder: A folder contains a set of logically creates a pair of intermediate raster ob- related objects in a Project File that have jects that reveal abnormal data variabil- been organized so they can be accessed ity. After the values in those raster ob- together. A folder is equivalent to a DOS jects have been edited to remove the data directory. (See also: nested folders.) spikes, the inverse transformation creates a raster object with the same image font: A single set of glyphs (characters, sym- as the original, but with lines or other bols, numerals, and letters of both upper noise removed. This Fourier Transform and lower case) of the same style (such as process has somewhat the same smooth- Times, Helvetica, or Schoolbook). Fonts ing effect as the low-frequency TNTmips can be stored and manipulated in comput- image filtering process. ers as bitmapped or vector (outline, or stroke). Font sizes are specified in points. frame: (video) A complete video image A 72-point font is one-inch high, from which consists of two interlaced fields. the highest ascender to the lowest de- Odd lines of the frame are contained in scender in the set. A 12-point font is 1/6 the primary field which is alternated with inch high. (See also: bitmapped font, out- the secondary field that contains the even line font, point size.) lines. The primary field lasts 1/60 of a second in standard broadcast video. The font set: A collection of one or more fonts secondary field follows in the next 1/60 that provide all the characters used by a of a second. The entire frame takes 1/ particular language. 30 of a second to display. There is a foreign key: A primary key in one table difference of 1/60 of a second between that also exists in another table within alternate lines in the image.

page 28 Glossary for Geospatial Analysis frame: (window) The border around a win- FSA: Farm Service Agency. dow in TNTmips. The active window frequency transform: An operation that (where any typing or selecting of op- breaks down an image into its fundamen- tions will occur) is indicated by a high- tal spatial frequency components for sub- lighted or different colored frame. sequent analysis or filtering. framegrabber and framegrabbing: Back- fuzzy C-means: An unsupervised classifi- ground: Prior to digital broadcasting, cation or clustering process developed by composite video and US standard broad- Robert Cannon et al. and documented in: casts repeated each field every 1/60 of a Robert L. Cannon, Jitendra V. Dave, second. Two interlaced fields, each con- James C. Bezdek, and Mohan M. Trivedi taining alternate lines of the image make (1986) IEEE Transactions on Geoscience up one video frame that lasts 1/30 of a and Remote Sensing. GE-24(3):400–408. second. Segmentation of a Thematic Mapper Im- A video framegrabber is a microcomputer age Using the Fuzzy C-Means Clustering interface board that accepts a video in- Algorithm. put signal and passes it to a color monitor. A program signals the video framegrabber to both freeze and digitize one video frame. — G — Digitizing a video frame may transform each picture element in the frame to a GAC : Global Area Coverage. single byte in the board’s memory. More commonly, it simultaneously captures, gadget: A graphical X object, like a widget, digitizes, and stores the video’s separate that does not have a window of its own red, green, and blue color values. Some (as most widgets do) but appears inside a framegrabbers can be set to grab only a parent window. single field to avoid the relative move- gap: A line segment undershoot leaves a blank ment between a frame’s two fields. If space in the T-junction of two lines. The the video comes from a camera that has raster thinning process often leaves gaps high-speed electronic shuttering (like 1/ that should be repaired by raster editing 1000 of a second), movement in the 1/ before final vectorization. 30 of a second between the primary field GEM: A window and mouse desktop operat- and the secondary field causes saw- ing system developed and marketed in the toothed edges on alternate lines in 1980's by Digital Research, Inc. straight features like road edges, and vertical poles. genlock: To synchronize two video signals (usually NTSC) to match the color video As soon as the video is saved in the board frames. Genlocking is necessary to mix memory (1/30 or 1/60 of a second), pic- and combine two signals, like a live video ture motion on the monitor freezes (even image and a graphic overlay. Some dis- if the live video input continues) while play boards can output an NTSC signal the data in the board memory is con- but cannot genlock, or mix, that signal verted into a display image. Then TNT- with another video signal. mips reads the memory of the board and transfers the image into project file ras- geocatalog: A geospatial catalog, or geocata- ter objects. log, gives a geographic overview of all the project materials in a selected direc- Framegrabber boards should not be con- tory on your system so that you can find fused with video digitizing boards, which all the objects in the same location as the gradually sample and construct a digital object in your current view and select representation of a still scene video im- them if desired. age. Sampling video boards represent an older technology, but are still used for geocoding: See: georeference. non-standard, higher resolution video geodesy: Investigation of scientific ques- sources. (See also: video digitizing board.) tions connected with the shape and di-

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mensions of the earth. geometric layer: A vector, CAD, shape, geoid: The figure that represents the irregu- TIN, or LAS layer composed of points, lar spheroidal shape of the earth is called lines, and/or polygons. the geoid. The geoid is an equipotential geometric transformation (or rectifica- surface (which means the direction of grav- tion): A process in which an image is ity is perpendicular to all points on the stretched differentially so as to change surface) at mean sea level. Because of its internal geometry is said to have un- variations in the distribution of the mass dergone geometric transformation or rec- and density of the earth’s constituents, tification. A transformation specifically the geoid generally rises over the conti- refers to the process of projecting an nents and is depressed in oceanic areas ; image from its plane onto another plane the geoid also conforms to various lumps by translation, rotation, and/or scale and depressions that depart from average change. smoothness on the earth’s surface. For georeference or geographic calibration: mapping purposes, the attributes found Information that relates raster cells or on the geoid must be transferred to a more vector/CAD elements to a specified co- regular geometric surface, an ellipsoid. ordinate system or map projection. The GeoJP2: A file with JPEG2000 compression RVC file format keeps the information and self-contained georeference informa- needed to relate every raster cell or vec- tion. No companion files are required to tor coordinate point to some geographic provide without additional files to con- coordinate system (like a particular map tain that information. (See also: projection) in subobjects associated with JPEG2000 compression.) the parent object. Geographic calibra- GeoLock: A standard View window / View tion may be established when creating an menu option that can be used when more object (like extracting an image map than one View window is open. Select from a Landsat or SPOT satellite im- GeoLock to open a menu where you can age). Calibration can also be added to an select the position locking feature or the existing object either by entering con- scale locking feature. When one of the trol points or by associating it with some locking features is selected, all open View calibrated object (like overlaying a cali- windows change in concert based on your brated vector to calibrate a raster). An locking choice. RVC subobject identifies a calibrated object’s map projection. geomashup: A geomashup combines geospatial data (such as maps, images, and point georeferenced image map: See: image locations) from multiple sources into a map. single interactive web page display. Geo- geospatial intelligence: the exploitation mashups commonly show geodata for a and analysis of imagery and geospatial particular area or a particular theme and information to describe, assess, and visu- overlay it on a global reference map or ally depict physical features and geo- image such as the proprietary map and graphically referenced activities on the satellite layers offered by Google Maps earth. and Bing Maps. The Application Program- geoviewer: The viewing component of lo- ming Interface (API) for Google Maps, cal and web applications that view geo- Google Earth, Bing Maps, or OpenLayers located source materials via the Internet, provides the geomashup with familiar such as Google Earth, Google Maps, Bing controls for panning the view and zoom- Maps, World Wind, and TNTmips. ing through different levels of detail. A tileset structure is the most efficient way GIF: Graphics Interchange Format. to store geodata for a geomashup. You gigabyte, Gbyte, or GB: A computer unit can create geomashups in TNTmips us- of measurement for 230 (approximately) ing the Assemble Geomashup process. (See 1,000,000,000 bytes, 1,000,000 kilo- also: Assemble Geomashup, mashup, bytes, 1,000 megabytes, or .001 tera- tileset.) bytes. (See also: bit, byte, exabyte, kilo-

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byte, megabyte, petabyte, terabyte, ally emulates the way in which Google yottabyte, zettabyte.) stores its proprietary satellite, terrain, and GIS: Geographic Information System. “A roads base layers that are accessible over Geographic Information System is a the Internet. Tiles for areas of the source computer system designed to allow users image that are to be treated as completely to collect, manage, and analyze large vol- covered by the tile are usually *.jpg. Tiles umes of spatially referenced and associ- are *.png where the area covered over- ated attribute data. The major compo- laps the regular or irregular outer edge nents of a GIS are: a user interface; sys- edge of the source image or an inner edge tem/database management capabilities; for missing internal areas. All tiles can database creation/data entry capacity; also be *.jpg or all *.png depending upon spatial data manipulation and analysis the desired appear of the source image in packages; and display/product generation the application. functions.” — from USGS Open File Re- GPIB: General Purpose Interface Board. An port 88-105 [A process for evaluating older interface standard for computers and Geographic Information Systems]. In the a peripheral devices, such as a scanner, broadest sense, a GIS is any integrated printer, or scientific instrument. system of information that includes a GPS: Global Positioning System. A network geographic component. of radio-emitting satellites deployed by global variable: (SML) All variables not the US Department of Defense. Ground- explicitly declared local are called “glo- based GPS receivers can automatically bal variables” and are insulated from the derive accurate surface coordinates for all operations of a function or procedure kinds of GIS, mapping, and surveying data only if the function or procedure declares collection. a local variable of the same name. gradient filtering: A method of edge detec- glyph: Characters, letters, numerals, and tion using two filters. One filter enhances symbols that make up a font typeface. horizontal edges and the other enhances Glyphs can include alpha-numeric char- vertical edges. The results are then com- acters, ideographs, international currency bined into a single output cell value. Gra- symbols, and directive symbols and icons dient filtering usually produces better re- such as curved arrows and dingbats. sults than a single high-pass filter. (See gnomonic projection: A type of perspec- also: filtering) tive azimuthal map projection. The point Grain Shape Index: One of the 12 fuzzy of the projection is the center of the properties that can be calculated for vec- sphere. Gnomonic is the only projec- tor objects. The Grain Shape Index mea- tion on which all great circles represented sures shape with a minimum value ap- are straight lines. proximating two for long skinny poly- Google Maps: A free, online, 2D, web map gons, pi for circles, and four for rectangles. service provided by Google. You can The Grain Shape Index can be very large view map (roads), satellite, or terrain- for fractals. The equation for calculating with-map base layers. Extensive search this property is: Grain Shape Index = capabilities are provided, inclding address Perimeter / Long Axis. search for parts of the world. Route plan- GRASS: Geographic Resources Analysis Sup- ning is also available from Google Maps. port System. A public domain GIS system Street View is another Google Maps developed at the U.S. Army’s Construc- viewer, which supplies drive-by images tion Engineering Research Laboratory in for an expanding number of cities (cur- Urbana, Illinois. It is now managed by rently in North America, Europe, and the GRASS Development Team. The sys- Japan). tem was designed for minicomputers and Google Maps Tile Overlays: A “Tile Over- has since been implemented on various lay” is the name Google uses for the struc- microcomputers. It is a raster-based sys- ture of a tileset that is optimized for its tem that can interface to vector data sets API to use as an overlay. It conceptu- for data preparation and import/export.

page 31 Glossary for Geospatial Analysis graticule: A network of parallels and merid- puted from Landsat MSS or TM images ians for equal intervals of latitude and lon- and stored in a raster object by Kauth’s gitude on the earth’s surface. The form greenness, brightness, wetness transfor- and appearance of a graticule depends on mations. the map projection employed. The lines ground control: Targeted terrain surface comprising a graticule may form a square features, such as road intersections, of / rectangular network; a graticule may known (surveyed) horizontal and verti- also be comprised of two families of curves cal coordinates used to orient and other- having variable separation between them. wise relate airphotos and satellite images The mathematical framework of a map to a map projection. is comprised of a grid, or a graticule, or both. A grid is always comprised of a ground range: The horizontal distance square network of parallel lines represent- along the ground for the flight path of a ing particular linear distances on the side-looking radar system. Ground range ground. is calculated by converting slant range using raster resampling and the flight pa- gray out: To dim a label that is nonfunc- rameters to correct the geometric dis- tional / unavailable in current context. tortions in the raw geodata. graytone or grayscale: An image or raster ground resolution: The limit of detail clar- object that contains tone levels and in- ity in an image of the earth’s surface tensities that grade gradually from black collected by some remote sensing device, (no intensity) to white (high intensity). usually measured in meters. An image Differences between one tone level and with a ground resolution of 10 meters another correspond to differences be- shows no ground features smaller than tween one data level and another. 10 x 10 meters. Each data cell in such an graytoned image or raster: An image or image contains a value for a distinct 10 x raster object that contains tone levels and 10 meter surface area. intensities that grade gradually from black ground truth: Information collected at the (no intensity) to white (high intensity). same site and at the same time as a re- Differences between one tone level and mote sensing system is collecting data. another correspond to differences between Ground truth is considered more accu- one data level and another. rate, and is used to interpret and cali- great circle: “A circle on a spherical surface brate remotely sensed observations. such that the plane containing the circle group or display group: Each view win- passes through the center of the sphere” dow in the TNTmips display process can (Random House). For example, the equa- include multiple groups of objects, and tor is a great circle. each group can contain multiple layers greeking: An on-screen substitution, such of objects. Groups allow side-by-side dis- as a wide gray line or an empty box, for play of related items in a single window. graphic text that is too small to be drawn TNTview does not provide group han- and viewed distinctly. dling tools, although you may encounter green biomass or phytomass: The amount groups as part of a display layout saved of wet weight or dry weight of growing, in TNTmips. chlorophyll-containing plant material per group list: A list in the control window of unit ground area. It is usually expressed in the display process that shows the cur- grams per square meter, tons per acre, or rently defined groups. metric tons per hectare. GUI: Graphical User Interface. A system greenness: The biophysical property of the program that provides windows and icons surface of the earth that indicates its green- and a way for the user to manipulate ness in a biological sense and gives a quali- them with keyboard and mouse. In the tative estimate of green biomass. It mea- X Window System, the GUI is a client sures plant vigor, water wellness, and chlo- and not part of the X server. Thus sev- rophyll content. Greenness can be com-

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eral different GUI’s are possible under X. nents to produce all colors. An HBS ras- TNTmips uses the LessTif GUI. ter set in TNTmips is a set of three rasters with the same dimensions that represent the hue, brightness, and saturation components of an image. — H — The hue-brightness-saturation model uses a six-sided pyramid (or hexcone) with the apex at the bottom to describe the col- handles: A tiny square used to mark a se- ors. Black is at the point of the hexcone lected graphic (non-textual) element at and the purest, most intense colors are at the corners or along the edges. Handles the top of the hexcone. Like the HIS can be dragged with the mouse to move model, on any horizontal slice of the cone, or resize the selected element. the hue varies as you move around the Hangul: Korean alphabetic system of writ- slice and the saturation increases as you ing created in the fifteenth century. move outward from the center. The HBS hanzi: Traditional written Chinese charac- model may be more intuitive than the ters which are not strictly tied to the HIS model, because the Brightness factor spoken language to the extent that mu- is at its most intense at 100%, rather than tually unintelligible Chinese dialects (such the Intensity factor which is most intense as Mandarin, Wu, Hakka, Cantonese) use at 50%. (See also: HIS, RGB.) the same written forms. HelpTip: Pop-up information that tells a hardcopy layout: A layout designed specifi- user how to proceed when using an APPLIDAT cally for printing. developed using TNTmips. The text for a HelpTip is stored as a subobject under hard disk or hard drive: A mechanical, the SML script for the APPLIDAT. This text magnetic storage device for computer file also specifies the delay and color data and program files. Internal hard scheme for the HelpTip. disks (sometimes called fixed disk) are mounted inside the computer chassis and HI:See: HyperIndex. so are not removable. An external hard hierarchical picklist: A picklist that is disk is an enclosed unit that is linked to a grouped by the values in another database computer by appropriate connecting field. cables. Hard disks are much faster and hierarchical tileset: The common popular hold much more than a removable floppy web geoviewers use hierarchical tilesets disk, but are slower than RAM disks. (See where a collection of subdirectories in also: floppy disk, RAM disk.) each directory contain all the tile files hardware key or software license key: for one prerendered zoom level. These A small device that contains sealed cir- directories are all arranged pyramid-style cuitry and is attached to a microcom- where each directory at a given level rep- puter (as through a USB, parallel, or se- resents a portion of the image at that rial port) to verify and authorize soft- level’s scale or zoom. MicroImages’ in- ware and hardware system configuration. ternal tileset raster objects use a hybrid TNTmips will not run on a microcom- approach combining both flat and hierar- puter that does not have a valid hard- chical structures. ware key. high-boost filter: A process that enhances hatch pattern: A polygon fill pattern com- and sharpens spatial features in a con- posed of line elements, rather than a tinuously varying raster object. (See also: bitmap. The line elements can be a filtering.) simple, solid color or a more complex highlight: A temporary color change to in- line pattern. The area between line ele- dicate attention to an element, such as ments is transparent. mouseover highlight. HBS:A method of defining color space, high-order characters: Characters in a sometimes known as HSV, that combines computer’s 8-bit character set above the hue, brightness, and saturation compo-

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standard 128 ASCII characters. High-or- life sightings that an animal or commu- der characters (also called “extended” nity of animals uses under normal condi- characters) are numbered 128-255, and tions. Environmental stresses may cause most PC’s use the IBM extended charac- a preferred home range to shrink, enter encoding scheme (also called the PC- large, or be abandoned. 8 character encoding scheme) for screen horse latitudes: The range of latitudes from display of the high-order characters. approximately 30–35° N and S over the The mapping of the high-order charac- oceans characterized by hot and dry ters to the text-mode character encoding weather and calm or very light winds. scheme of a particular printer is not stan- hot spot: See: symbol hot spot, cursor hot dard. In order to see what characters a spot. printer provides for the high-order characters, consult the printer’s documenta- HPGL: Hewlett Packard Graphics Language. tion or generate your own test page. In A protocol language used by a number of some application software, in order to pen plotters. get a printer to generate a particular char- HTTP: Hypertext Transfer Protocol. acter, you may have to use a different hue: One of the three coordinates needed character on the screen. to specify a color in the HBS and HIS high-pass filter: A process that enhances color domain. Hue tells the color such as and sharpens the boundary edges in the red, blue, or green. (See also: HBS, HIS.) spatial features of a continuously varying hull: A hull is the two dimensional area for raster object. (See also: filtering) which a TIN is generated. Within the hiragana: Cursive form of kana. hull, including its edges, the Z value at HIS: Hue, Intensity, and Saturation. Some- any X-Y position can be interpolated. A times called HLS, for Hue, Luminance and hull is convex when all lines that con- Saturation. The system of defining video nect two points on the hull boundary fall output color from hue, intensity and satu- entirely within the hull. A hull for a U- ration characteristics. HIS controls are shaped area, for example, is not convex. commonly used with color television sets. hydrography: The description and study Most computer displays use RGB (red/ of bodies of water or their representa- green/blue) color mixing information in- tions on a map. stead. HyperIndex® or HI: A TNTmips process The hue-intensity-saturation color model that creates and manages large collec- uses a double cone (with its greatest cir- tions, called stacks, of graphically indexed cumference at the midpoint of the z-axis) objects (raster, vector, CAD, text and to describe specific colors. On any hori- database objects). You can retrieve zontal slice of the cone, the hue varies as HyperIndexed images and information you move around the slice and the satura- from the object hierarchy by selecting a tion increases as you move outward from feature of interest (or “index area”) in the center. Intensity is the z-axis of the the current display image with the mouse. model. The shades of gray are found along (See also: index area, stack.) the z-axis, where hue and saturation equal hyperspectral image: Imagery acquired by zero. (See also: HBS, RGB.) hyperspectral remote sensors that col- histogram: A graph of the number of times lect image data simultaneously in dozens a value occurs across a range of possible or hundreds of narrow, adjacent spectral values. One axis of a raster histogram bands. (See also: mulispectral image) shows how many times a cell value is hyperspectral object: A hyperspectral im- found in the raster. The other axis shows age can be stored in a TNTmips Project the range of possible data values (like 0 to File in one of two ways: as a set of sepa- 255 for 8-bit cell values). rate raster objects with one object for home range: The area defined by a swarm each wavelength band or as a single of spatial observation events. Classically, hyperspectral object, or hypercube, that the home range is the area defined by wild-

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includes raster value and wavelength in- IETF: Internet Engineering Task Force. formation for all the bands in a Ikonos satellite: A satellite that collects high hyperspectral image. resolution imagery providing 1m panchro- hypsography: Measurement and mapping matic or 4m multispectral imagery. A of the variations in earth surface eleva- pan sharpened multispectral product is tion in reference to sea level, which are also available. often represented by contour lines on image: Any analog or digital two-dimen- maps. sional array of values whose spatial inter- connections convey useful information. Image has a wider sense than photographs, TV, or human vision. A photographic — I — print is an image but an image is not necessarily a photograph. What a human sees can be called an image but image is ICC: International Color Consortium. The not restricted to describing human vision. ICC developed the profile formats used The raster scan of a color map is an im- to tell hardware devices how to produce age until it is reduced to a vector object. sRGB colors. However, the display of a vector object ICM: Image Color Matching or Integrated on the monitor creates an image of that Color Management. Also the file exten- vector file. Properly, that which is stored sion used by Microsoft Windows for pro- in a raster object can be called an image, file files. but that which is stored in vector, text, or icon: A stylized representation of an object database objects cannot. that consists of an image and a label. A image map or georeferenced image map: window icon is a minimized representa- An image that has been processed to be tion of a window or window family used like a map in appearance, scale, geom- to help organize windows and tasks in etry, boundary, and projection with a de- the display. Iconifying a window changes gree of precision that satisfies the user. nothing about the state of the active pro- Measurements made from an image map cess in the window. yield results equal to those made from the icon button: A button with a simple picture corresponding planimetric, topographic, and a ToolTip to identify its function, or other map. Similarly, either the image which is usually found on a toolbar but map or the conventional map can be over- may be found in isolation in some soft- laid and matched with the other. ware products. For example, a 7.5' image map prepared ideograph: A symbol that represents mean- in TNTmips from Landsat or SPOT sat- ing without indicating pronunciation. ellite images will accurately match the Often opposed to “phonetic.” Chinese corresponding USGS topographic map. is often, but erroneously, called an ideo- Similarly, the color scan of a topographic graphic language. Its origins (like those map that has been assembled by tiling and of Western alphabets) were ideographic calibrated to map coordinates is an image and pictographic, but it is more accu- map. (See also: nominal image map.) rately described as a “morphosyllabic:” a impedance: The opposition to flow along a combination of syllabic characters with given line; that is, the cost of traveling nonphonetic techniques, such as along a given line. determinatives, to suggest the meaning impedance limit: The maximum imped- category of written items. ance allowed for any path to a center in IDIMS: A minicomputer, raster-based im- the allocation mode of the Network age processing system originally devel- Analysis process. oped by NASA then sold to TRW and implied georeference: A georeference that then to Terra-Mar and ported to the PC. uses geographic coordinates as element IEEE: Institute of Electrical and Electronics coordinates (object coordinates = geo- Engineers.

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graphic coordinates). Vector, CAD, and the TNTmips Object Editor used to cre- TIN objects can have an implied ate vector or CAD lines. georeference. interface: The type of signal protocol for importing vector, CAD, or raster objects: connecting computer devices. You can Decoding the raster data values or the only connect a peripheral device to a vector/CAD coordinates in another microcomputer through a matching in- system’s format and converting them to terface. Common interface types include TNTmips project file objects. Color serial, parallel, SCSI and GPIB. schemes; arc, node, and polygon struc- interface card: Any electronic circuit board tures; geographic calibration; and all other installed in a microcomputer that handles supporting data is converted into the ap- translation between the computer and propriate subobject as long as their for- some particular hardware device. For ex- mat can be decoded from their developer’s ample, an interface board may translate information or determined from sample output data into display signals for an files by MicroImages. image display monitor, or translate in- index: Special data structure used in a data- put signals from a color scanner into digi- base to speed searching for records or spa- tal data for the computer. tial features in geographic data sets. interlaced video: Background: The im- index areas: The regions in a HyperIndex age you see on a TV screen is made from parent object linked to a daughter object, a set of about 480 horizontal lines. The which may be rectangular, circular, or lines are projected in two passes of the quadrilateral in shape. HyperIndex will signal beam. Each pass only projects display the daughter object when the every other line of the image: the odd mouse selects a point within the index lines in one pass, and the even lines in area. Active index areas can be revealed the next pass. One scan takes 1/60 of a on the display of the parent object when second, so the whole picture (the frame) the option “Show Index Areas” under the is refreshed every 1/30th of a second. View window menu HyperIndex is on. (See There is a time difference of 1/60 of a also: daughter object, link, parent object.) second between any pair of adjacent lines infinite loop: see loop, infinite. in a frame. INFO: The database program used by ARC/ Thus, a single, still video image of 1/30 INFO. (See also: ARC/INFO.) of a second duration consists of two interlaced fields of the source video signal. input redistribution: Automatic redistri- Displaying a single frame of interlaced bution (rescaling) of the cell values in each video causes vertical jitter. This jitter is input raster object prior to classification especially pronounced when an image in the Auto-Classify process. contains horizontal lines. This is called integer: A number without a decimal, such as umpire shirt jitter on conventional broad- 0, 8, and -3. cast TV and can be seen along the black intensity: One of the three coordinates and white edges of an umpire’s shirt or needed to define a color in the HIS color along the sharp horizontal edges of large domain. Intensity represents a color’s letters. This effect can cause eye strain. brightness or average radiance level. In- Interlace jitter is best overcome by using tensity data is very similar to the infor- a monitor with long-persistence phos- mation in black and white representations phor. This phosphor holds each line of color images. (See also: HIS) longer until it can be refreshed by the next scan. interactive line-following: The Interac- tive Line-Following process lets you in- internal database: A database created by a teractively trace easily distinguishable lines TNT product maintained in RVC format. in a RGB, or color separated, type raster (See also: database object, external data- object and create vector (or CAD) ele- base file.) ments with minimal guidance. Interac- internal tables: Information that is auto- tive Line-Following is a tool available in matically created in the TNT products

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for vector, shape, and TIN objects and interpretation: Identifying and grouping some raster types, but is not shown by classes of features in an image. TNT- default with the user-defined tables. In- mips provides three kinds of interpreta- ternal tables include internal object in- tion processes: Interactive (Feature Map- formation, which is not actually main- ping), Automatic (simple clustering, K- tained in tabular form but is provided so means, fuzzy C-means, and minimum dis- that you can view the standard, internal tribution angle), and Semiautomatic information for each and every element (maximum-likelihood ratioing, stepwise in vector, shape, and TIN objects and linear discriminant analysis, and Suits- for each cell in some raster object types. Wagner classification). In a fully inter- Each element type in vector, shape, and preted image, every pixel is assigned to a TIN objects has its internal table. Inter- class. In many cases, partial interpreta- nal tables are not available for CAD ob- tion is adequate, such as just showing cul- jects because they require referencing by tivated land, or just showing wetlands. element number interpreted programming language: (as The internal tables keep track of all to- opposed to a compiled language) A com- pology information for vector elements, puter language that is evaluated and ex- what elements are connected in TIN ob- ecuted by the system one command or jects, and element numbers in directly statement at a time. By contrast, a pro- display shapefiles. To view internal gram in a compiled language is completely tables, use the Show System Tables right evaluated and translated into machine mouse button menu option at the ele- code by the system before any of it is ment level of a layer manager window. executed. (See also: system tables.) intersection: A merging of two vector ob- internationalized X application: A projects such that only the elements in the gram for the X Window System that is shared area of the two objects are copied not “hard wired” to any specific language to the resulting vector. or culture, and so is capable of operating inverse distance: Value used in some statis- using a single user-selected language and tical calculations and equal to one divided set of cultural conventions. The TNT by the distance between two points of products can be used in any language and interest. script in the world. ISA: Industry Standard Architecture. One of Internet: a global comptuer network con- the bus architectures for microcomputers sisting of thousands of networks typi- used in PC/XT and PC/AT. Replaced in cally interconnected by fiber optic ca- 1993 by Plug and Play ISA (See also: bus.) bling. It had two parent networks whose ISO: International Organization for Stan- joining began the ongoing evolution: (1) dardization. The ISO defines and pub- U. S. Military (Tactical communication lishes standards that can be adopted by in the event of telephone downtime dur- many manufacturers. For example, one ing wartime) (2) Academics (Shared in- ISO standard defines the format for eras- formation between researchers). able optical disks, so they can be used on interpolation: Applying mathematical es- drives from any manufacturer that sup- timation techniques to sets of numbers ports the standard. to find intermediate values. Interpola- ISO 10646: A character encoding scheme tion is a collective term for various tech- that is a super set of the ASCII, Latin-1, niques of determining an approximate and Unicode character sets that has room value of a function at a point in the do- for 4,294,967,296 characters (a 32-bit main between given points at which the or 4-byte character encoding scheme). Ul- function values are known. Bilinear in- timately, ISO 10646 will assign codes to terpolation, for example, is based on the every known symbol and character of presumption that the value being sought both modern and ancient languages. lies on or near a straight line joining two known values. (See also: convolution.) ISODATA: Iterative Self-Organizing Data Analysis. An unsupervised classification

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method in the Auto-Classify process. linear combinations of the Landsat TM isoline: A line connecting points of equal spectral bands which computationally re- value. Examples are contour lines and duce the images to maps of a site’s green- lines depicting ocean temperature gradi- ness, brightness, and wetness. Kauth, a ents. scientist at the Environmental Research Institute of Michigan, extended the green item: Anything that can be placed on the biomass concepts developed by Dr. Lee page in the page layout design process, D. Miller, a principal of MicroImages, including rasters, vectors, CAD objects, to extract more biophysical information text files, scale bars, and tick marks. The from Landsat MSS and TM multispec- page layout process provides tools to se- tral images. He developed the combina- lect, size, and position items. tions by carefully correlating ground measurements made by Miller and others with values in the satellite images. The plots of the data distribution in the original — J — spectral bands resemble a tasseled cap — hence the general name by which these transformations are called. Java: A simple, platform-independent programming language for writing applets, key field: A field in a database table identi- which are obtained by a client from the fied as of importance is designated a pri- Internet and run on the client’s machine. mary key. There can be only one primary key in a table. A primary key field JavaScript: Netscape’s simple, cross-plat- must have unique entries for each record form, Internet scripting language that runs in the table. A primary key field also may in a limited number of environments. not be blank in any of the records in a JPEG: Joint Photographic Experts Group table. A foreign key is a field with the responsible for the standards for still im- same name as a primary key that is lo- age compression formats, such as JPEG, cated in a different table. Foreign keys JBIG, and JPEG 2000. are identified automatically when pri- jumper: A physical connector on a micro- mary keys are designated in other tables computer circuit board that bridges two attached to the same vector/CAD ob- neighboring terminal posts. The jumper ject. (See also: database, foreign key, is either slid down onto the posts or re- primary key.) Primary and foreign key moved according to the configuration op- relationships between tables let you es- tions described in the documentation that tablish computed fields that incorporate came with the device. values from more than one table in their defining expression. kilobyte: A unit of measure equal to 1024 bytes (2 to the 10th power), but loosely used for 1,000 bytes. So also with its — K — multiples: megabyte (loosely 1,000,000 bytes), gigabyte (loosely 1,000,000,000 K or KB: See: kilobyte bytes) and terabyte (1,000,000,000,000 kana: Japanese syllabic characters derived bytes). (See also: bit, byte, exabyte, from Chinese. There are two varieties: gigabyte, megabyte, petabyte, terabyte, hiragana and katakana. yottabyte, zettabyte.) kanji: Japanese term for Chinese charac- K-means: An iterative method of unsuper- ters. vised classification (clustering). The n- katakana: Angular form of kana, roughly dimensional raster space is divided into parallel to Latin block letters, and used K clusters. The cluster means are used to much like English italics. determine cluster membership. After all cells are processed, new cluster means Kauth’s Tasseled Cap Kauth’s green- or are determined and the process is repeated ness / brightness / wetness: A set of

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a predetermined number of times or un- You choose labels (names for types of til convergence is achieved. features) based upon your knowledge of KML: Keyhole Markup Language. These the areas or materials in the image. Use files are used to provide overlays in the TNTmips Feature Mapping process Google Earth and Google Maps. You can to label (and possibly combine) the clus- render any display in the TNT products ter map output of automatic image inter- to KML for viewing in combination with pretation processes. their native imagery. LAI: See: leaf area index. Kuan (Adaptive Noise Smoothing) fil- LAN: Local Area Network. ter: Filter that removes speckle from land cover: The materials that cover a study radar images using a minimum mean site, such as vegetation, bare soil, rock, square error calculation to estimate the sand, and water. value of the true signal for the center cell in the filter window. The filter then Landsat satellite: A satellite that collects calculates the signal estimate from the multispectral images. At various times it local mean and variance and the noise uses 1) a Return Beam Vidicon (RBV) de- standard deviation. vice, 2) the Multispectral Scanning (MSS) device, and 3) the Thematic Mapping Kuan (MAP): Kuan Maximum A Posteri (TM) scanning device. Landsat also re- filter; this filter removes speckle from lays data from ground observation sta- radar images using a maximum likelihood tions. Landsat was originally called the probability approach to estimate the true ERTS or Earth Resource Technology Sat- signal value for the center cell in the ellite. filter window. The filter then maximizes a probability function involving the cen- LAS: The file extension for LiDAR data. ter cell value, the local mean and stan- Also the file extension for latitude-shift dard deviation, and the noise standard files used in TNTmips by one of the geo- deviation. detic conversion methods. Latin alphabet: The character encoding scheme used by most Western nations, based on the alphabet developed in Ro- man antiquity, itself a derivative of the — L — Greek and Western Semitic alphabets. The Latin alphabet is used by the lan- label: (CAD context) A CAD element that guages of Western Europe, including En- contains text used to identify a point, glish, as well as many other languages such line or polygon element. as Turkish, Swahili, and Vietnamese. The label: (vector context) Text in a vector Latin alphabet is sometimes referred to object used to identify a point, line, or as the Roman alphabet, but “Roman” is polygon element. TNTmips can create not used in this discussion so as to avoid label text automatically from attached confusion, since the term “Roman” is of- database tables. Also, you can manually ten used in typeface and character style assign arbitrary labels independent of contexts. class membership that need not be asso- Latin-1: (also known as ISO 8859-1) A ciated with individual elements. super set of the 7-bit ASCII character en- label: (window context) The static text part coding scheme that includes various sym- of a component that presents informa- bols plus letters with diacritics commonly tion to the user about that component, used in European languages. Latin-1 is an such as the action invoked by a push but- 8-bit character encoding scheme, contain- ton or the mode selected by a check but- ing 256 characters. Latin-1 makes dif- ton. ferent assignments for codes 128-255 than does PC-8. Latin-1 is, however, con- labeling: (raster context) Identifying and sistent with the Unicode and ISO 10646 grouping the clusters that result from any standards, and is the common encoding kind of automated image interpretation. scheme used by Unix systems.

page 39 Glossary for Geospatial Analysis latitude: The angular distance in degrees of values that are not used in the process. a point on the earth north or south of the line: (raster) One horizontal row of cells equator. (or pixels) in a raster object (or display layer: A display entity comprised of one or image). (vector, CAD) An ordered set of more components that can be manipu- coordinates that represents a linear fea- lated separately from other layers. There ture (see: line element). is often a one-to-one correspondence be- linear contrast: See: contrast. tween layers and objects in TNTmips, but an individual layer may be comprised of linear transform: (map registration) One multiple objects, such as the red, green, kind of map registration subobject and blue components used to create a (Regist) that contains an object’s math- single layer in multiple raster display. Each ematical representation for its calibra- group in the TNTmips display process tion solution (least squares) derived from may be composed of multiple layers of a control point list. objects. The background layer may be line element: One of the types of ele- overlaid by a raster object, such as an ments that make up a TNTmips vector airphoto, which may in turn be overlaid object. A line is defined by an ordered by layers of CAD and vector objects string of coordinates, which define a which show soil boundaries, roads, or pin- curved path in space. Line attributes in- mapping symbols. clude: layer list: The layer area of the control win- Vector element class attributes may be dow in the TNTmips display process cross-indexed to a list containing the el- shows the objects and drawing order of ement drawing style, which may include the current layers. polygon fill pattern, line drawing pattern, point symbol, line width or sym- leaf area index or LAI: A unit-less, biologi- bol/point size, RGB color, RGB label cal measure equal to the ratio of the one- color, RGB fill color, label font number, sided surface area of the leaves in an in label font size, label font zoom factor, situ crop, forest, or grassland canopy to label font style, and label rotation angle. the ground area. line pattern: The drawing style of a line least squares: A mathematical method for for display or printing. TNTmips lets fitting a line or curve to a set of data you create and assign line patterns to points. Least squares minimizes the sum vector and CAD line elements by class. of the squares of the error term at each You can control the width, color, and point. design (dashes, outlines, center stripes). legend: The area on a map that provides a Line patterns can be designed from the key to the colors, patterns, and symbols 64 standard colors plus transparent (so used in the map. the underlying image shows through). level: In HyperIndex, any object or file that link: (to external database or raster object). is displayed in the Display / Spatial Data A project file link to an external data- window is called a level. A level may origi- base file contains the file name, device nate from a raster, vector, or CAD ob- location, and field/record information ject. However, in HyperIndex, the level about the database file. When a TNT assumes an identity beyond that of the product accesses the database, it depends object or file itself, because the level in- on the link information to find and ma- cludes the index areas that have been de- nipulate the information contained fined and any links to other objects. Thus, therein. If an external system moves or in addition to being an image, a level lets restructures the database, the project file you access many different kinds of infor- link must be created again. A project file mation. (See also: HyperIndex, index area, link to an external raster format con- link, stack.) tains the file name and path. For the limit line: An adjustable graphic line on a most part, linked raster files are treated process control screen that defines the just as internal raster objects. Subobjects boundary between values that are used and created for use in the TNT products, such

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as histograms and pyramids, are stored radar sensor is pointing when transmit- with the project file link. ting and receiving for a particular cell in link: (HyperIndex). The relational con- an image. nection between a region (or index area) loop, infinite: see infinite loop. on a parent object and daughter object in low-pass filter: A process that smoothes or a HyperIndex stack. When a user clicks reduces the spatial variability or detail in on an index area on a parent object, the a continuously varying raster object. (See link tells TNTmips how to retrieve the also: filtering) daughter object on the next level. The user who creates the HyperIndex stack LSCV: Least-Squares Cross Validation. A defines the links as the stack is built. (See statistical method. also: daughter object, HyperIndex, index area, parent object, stack.) list box: A scrollable list of options from which to choose. — M — local engineering: A type of georeference that relates one obect to another with- manifold: The 3D surface defined by the 3D out specifying a Coordinate Reference control points assigned to the vector or System or relating it to a position on the raster object onto which the vector or Earth. raster object is then projected. Used in- terchangeably with manifold surface. local variable: (SML) Variables that be- long to a function or procedure and exist mapping unit: See: soil mapping unit only for that procedure are “local vari- map projection: “A device for representing ables.” No variable is local unless it has all or part of a rounded surface on a flat been explicitly designated so with the sheet. Since this cannot be done without “local” statement in the function or pro- distortion, the cartographer must choose cedure. A local variable may have the the map characteristic (area, shape, scale, same name as a variable used elsewhere direction) which is to be shown accurately in the program without affecting it. at the expense of others.” Map Projec- locale: One collection of data that defines tions Used by the U. S. Geological Sur- the semantics for a specific language and vey, Geological Survey Bulletin 1532, Sec- set of cultural conventions. Standard C ond Edition, U. S. Government Printing provides a Locale structure which includes Office, Washington, D.C., 1982, p. 5. The six aspects of the local culture and lan- map projection geometrically or math- guage: 1) Collation / sort sequence for ematically generates the grid of lines of characters, 2) Character type, 3) Money latitude and longitude. and currency symbols and formats, 4) Every process that establishes or trans- Numerical formats: a point or comma lates map projections offers the same stan- for decimal demarcation, 5) Time - dard selection list of projections. The names of the weekdays, 6) Messages - practical choice of map projections for yes/no, program status and prompts. ungeorefer-enced project materials is nor- localization: Providing the run-time data mally determined by the kind of projec- that describes the necessary elements of tion used by those project materials that a locale for an internationalized program are calibrated to a projection. For ex- so it can use the correct character en- ample, if you have a scanned USGS topo coding scheme, font, keyboard conven- map in the polyconic projection, you may tions, collation sequence for the alpha- decide to calibrate (or translate existing bet, and so on. calibration) satellite images and vector overlays to the same projection. (See longitude: The angular distance in degrees also: ellipsoid.) of a point on the earth east or west of the Prime Meridian. map quadrangle or map quad: The geographic area covered by a map. One kind look angle: The direction an antenna of a of map quadrangle is the 7.5' x 7.5' area

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that is covered by a standard USGS 7.5' maximum-likelihood classification: A topographic map. Referring to a 7.5' map supervised image processing routine usu- quadrangle does not imply the presence ally applied to multivariable images that of an actual paper map. The term may have a dimensionality greater than 3. simply designate the area covered by elec- First, the user selects sample areas, (called tronically stored materials. prototype or training set areas) for each map scale: The relationship that exists be- feature to be mapped. The maximum- tween a distance on a map and the corre- likelihood process then computes the sta- sponding distance on the earth. It may tistical properties of these features. Simi- be expressed as an equivalence, one inch larly, it determines the statistical char- equals 16 statute miles; as a fraction or acteristics which separate feature types. ratio, 1:1,000,000; or as a bar graph (sta- After this identification model has been dia bar) subdivided to show the distance built, the process tests each cell to deter- that each of its parts represents on the mine in which prototype group it most earth. probably belongs. A threshold can be set so that if the highest probability of a map scale control: The ability to turn feature match is below the threshold, the groups, layers, and elements on and off cell is designated as unknown. This dependent on the map scale of the dis- “catch-all” group insures that a cell rep- play. resenting a feature type not defined in marking features: Saving prototype areas one of the training sets will not be forced that have been classified in feature map- into membership. ping, clustering, or some other TNTmips maximum movement for steadiness: interpretation process as permanent fea- greatest allowable movement of locations tures. Marked features can be unmarked. of class centers in each iteration of the (See also: labeling) Auto-Classify process. Specifying maxi- mark: To select one or more of a group of mum movement for steadiness in this elements in preparation for acting upon process limits the number of iterations them by some program operation such as of the process. move, copy, edit, open, analyze, display, maximum zoom level: The maximum or delete. zoom level or most detailed zoom level mashup: (software) A web page or applica- contains the tiles that provide the maxi- tion that combines features from more mum detail in content that is available in than one source into an integrated expe- the source image or map. It sets the rience typically using an API to acquire maximum resolution at which the area content developed by others. For ex- covered by the tileset can be viewed. A ample, TNTmap Open that uses an API tileset must use predetermined zoom lev- from OpenLayers and the extended els and thus the source image or map is Google Maps that launches from TNTmap unlikely to match any of these zoom Builder and uses the Google Maps API. levels in detail or resolution. Thus the mask or data mask: A processing barrier or maximum zoom level is usually set to be boundary that only allows selected data the zoom level that is the closest match values (perhaps in a chosen range or area) at a higher resolution or detail to the to pass. Users might choose a data mask resolution of the source image or map. that blocks all values outside a selected MCA: Micro Channel Architecture. The value range, eliminating all image features 32-bit bus architecture introduced for except those in the range they want to 80386 IBM PS/2 machines in 1987. use in a process. A mask is more often medium Average or middle; a choice for used to confine the effects of a process to smoothing options in some TNTmips a selected area of a raster object. (See processes. also: processing mask.) megabyte, Mbyte, or MB: A computer unit matte: The background, surrounding area, and of measurement for 220 or (approxi- border for a group, primarily legends, in a mately) 1,000,000 bytes, 1,000 kilobytes, layout.

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.001 gigabytes, or .000001 terabytes. edges of the box indicate a minimum or (See also: bit, byte, exabyte, gigabyte, maximum coordinate value for that ele- kilobyte, petabyte, terabyte, yottabyte, ment. zettabyte.) minute or ': “The sixtieth part of a degree menu: A pulldown or popup list of selection of angular measurement, often repre- options. sented by the sign ‘ as in 12° 30’, read 12 menubar: A graphic component at the top degrees, 30 minutes” (Random House). of a window that displays the titles of USGS quadrangle maps are common in the pulldown menus. both 15 and 7.5 minute sizes. For example, the 7.5 minute map for Crow meridian: A great circle on the earth’s sur- Butte, Nebraska covers from 103° 15' to face that passes through the terrestrial 103° 22' 30" west, and 42° 37' 30" to 42° poles. All locations on the circle have 45' north. (See also: arcsecond, degree.) the same longitude. MIPS: Map and Image Processing System message box: A type of dialog box that from MicroImages, Inc. First marketed contains a message or warning provoked for DOS computers in 1986. (See also: by a user request or processing condi- TNTmips.) tion. The user must respond (for example by selecting the OK push button) miter: one of the joining methods for line before the interrupted process can re- and polygon segments when creating off- sume. sets for vector elements in the Spatial Data Editor. The Miter option creates a metadata Information stored in a subobject single vertex where the segments meet at attached to an object. This information an angle. can includes the source of the geodata in the object, the date the image was cap- mnemonic: A single keyboard character as- tured, the scale of the image, the loca- sociated with a labeled component (such tion of the image, and so forth. as a push button or menu selection). The mnemonic is underlined in the label, or if MI: MicroImages, Inc. the mnemonic is not contained in the MICROPIPS: An early raster-based micro- label, it can follow the label in parenthe- computer image processing system. ses. The underscore in the menu selec- MIDI: Musical Instrument Digital Interface. tion “View”, for example, indicates that the letter “V” is the mnemonic for that MIME: Multipurpose Internet Mail Exten- selection, and that pressing the “V” key sions. on the keyboard will activate the View minimum distribution angle: An unsu- selection. (See also: accelerator.) pervised classification or clustering pro- model area: The area of overlap in a pair of cess developed by Dr. Jack Paris and pre- stereo images that is selected for creation sented in: Jack F. Paris and Helenann H. of a DEM. Kwong (1988) Photogrammetric Engi- neering and Remote Sensing 54(8):1187– MODIS: Moderate Resolution Imaging 1193. Characterization of Vegetation Spectroradiometer that collects multi- with Combined Thematic Mapper (TM) spectral images aboard NASA’s Terra and Shuttle Imaging Radar (SIR-B) (EOS AM) and Aqua (EOS PM) satellites. Image Data. These satellites view the entire earth’s surface every 1 to 2 days with the ability minimum zoom level: For tilesets, the to directly broadcast in real time its raw minimum zoom level, or least detailed data to appropriately equipped ground sta- zoom level, contains the tiles that pro- tions. vide the most synoptic or overall view of the area covered by the tileset. It is monochrome image: An image displayed the lowest resolution at which the area in a single color or shades of a single color. covered by the tileset can be viewed. morphological analysis: A process that al- min/max box: A rectangle that encloses a ters or extracts shapes within an image. vector or CAD element such that the The morphological functions provided in

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TNTmips are dilation, erosion, opening, MRI: Magnetic Resonance Imaging. A tech- closing, clump, and sieve. nique used in medicine to collect com- mosaic: A large image assembled from seg- puter images of internal organs and sys- ments. Each segment may come from a tems for examination and evaluation. A different source and have a different cell device used in medicine. size and angle of orientation, but all the ms (millisecond): One thousandth of a segments must be geometrically rectified second. A measure of average disk access and calibrated to a common coordinate time (the time it takes the drive to posi- framework. The mosaic process rotates tion the read/write head over the re- and re-scales each piece and creates a quested track). single combined object. If all segments MSS: Multi-Spectral Scanner. A sensing de- are georeferenced to the same map pro- vice on the Landsat satellite that col- jection, they can be automatically lects simultaneous images over multiple mosaicked based upon their geographic ranges of the spectrum. calibration without additional adjustments. Recognized verbal forms of mosaic are multi-byte strings: Text in some charac- mosaic, mosaicked and mosaicking. ter encoding schemes exceeds the 256- character limitation of single byte en- MOSS: Map Overlay and Statistical System. coding. In multi-byte systems, charac- A pioneer vector-based geographic infor- ters are allotted 2 or 4 bytes each. mation system (GIS) developed and still widely used by groups in the USDI, espe- multi-frame capture: Capture of two or cially the USF&WS and BLM. MOSS vec- more frames in a video. tor data files contain strings of coordi- multilingual application: A computer nate pairs which describe closed polygo- program that allows the user to mix mul- nal areas, lines, and single point features. tiple languages and character sets is said Common boundaries between adjacent to be multilingual such as a word proces- polygons are repeated twice in this data sor that allows side-by-side columns of structure, once with each polygon. Much English and Japanese, or even mixture geographic data is available in this for- of Latin characters within a longer Japa- mat, especially that portion of the NWI nese text. Multilingualization is more wetland maps which have been digitized. complex than internationalization, motherboard: The main circuit board in a which limits the program to one local microcomputer. The motherboard nor- language at a time. TNTmips offers mally contains the main processor, logic multilingual support, paticularly with chips, memory, and expansion slots for annotation tools for map and poster lay- optional circuit cards. out which allow mixing fonts of different character sets. Thus for example, it mouse: A computer graphics pointing de- is possible to create a map that has both vice. As you move a mouse across the Thai and English annotations. desktop, the mouse cursor moves across the image display. multiple raster set: A set of coextensive raster objects displayed in unison. When mouse cursor: Shows the position of mouse the multiple raster display mode is RGB, activity or focus on the screen. The mouse HIS, or HBS, three objects are included cursor changes shapes to show the func- in the set. When the multiple raster dis- tion currently assigned to the mouse. For play mode is RGBI or RGBB, four ob- example, an arrow pointer indicates that jects are included. One object in the set is the mouse may be used for selection. An assigned to each display component. hourglass or clock shape shows that the mouse is inactive during a processing ac- multisensor images: Coregistered images tivity. with the same cell size collected by different sensing devices. For example, a mouseover highlight: A color or other 10-meter SPOT panchromatic image can change to identify the element the mouse be coregistered with a resampled Landsat is paused over. TM image so that their cells correctly mouse pointer: See: mouse cursor match. This combination is called a

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multisensor image. ministration. multispectral images: Images optically navigation: Moving a selection highlight or acquired in more than one spectral or location cursor with a mouse or keyboard wavelength interval. Each individual through the levels of a menu and window image is usually of the same physical area system. and scale but of a different spectral band. ND, ND6 and ND7: Normalized Difference. The MSS and TM sensors aboard the Vegetation index computations developed Landsat satellite both collect simultaneous for use with Landsat MSS. These vegeta- multispectral images. The TM sensor tion indices are now commonly used with scans and stores seven individual images any image that has the required spectral in spectral bands ranging from the blue bands. The bands required are approxi- wavelengths up to those in the thermal mately equivalent to the red and the infrared. photo-infrared spectral bands measured multitemporal images: Coregistered im- by color-infrared film. The ND6 index ages collected at different times by the used MSS band 6, and ND7 uses band 7. same device. For example, airvideo im- Since these two Landsat MSS infrared ages collected one year apart, digitized, bands are so highly correlated, similar re- and warped to the same geometry are sults are possible using either of the com- called multitemporal images and can be putations or with any images that have analyzed to map the changes between an equivalent photo-infrared spectral the dates. band. Good color-infrared image sources multivariable images: An image stored for processing into an ND or green biom- on more than one independent, ass raster include Landsat MSS and TM, coregistered raster. For example, a video SPOT CIR, 35mm CIR film, 9" CIR film, frame-grabbed image stored as indepen- and CIR video. dent red, green, and blue rasters is a mul- near range: That portion of a synthetic tivariable image. So too is any aperture radar (SAR) image that is near- multitemporal, multispectral, or est the aircraft flight path. multisensor image. nearest neighbor sampling/interpola- multivolume project file: A project file tion: Resampling a source raster to yield that is spread over more than one media a new raster with a different cell size, ras- unit by linking to objects on other deter orientation, and/or internal geometry vices. by computing the distance between the center of each cell in the output raster and the 4 nearest cells in the input raster. The data value for the closest input cell is assigned without alteration to be the data — N — value of the output cell. Therefore, the input value of one input cell may be as- nadir: The point on the ground vertically signed to more than one output cell. It beneath the imaging sensor. That is, if also means that some input cells may not you imagine a straight line drawn from a be transferred at all to the output raster. sensor to the center of the earth, the These undersampling and oversampling nadir is point where that line intersects situations occur when the cell sizes of the the surface of the Earth. For radar imag- input and output raster are different. ing, the nadir corresponds to the begin- For example, a resampled output raster ning of the near range. which is coparallel to the input raster but NAPP airphotos: National Aerial Photog- which has cells half as big, will repeat the raphy Program airphotos. USGS CIR high input values in a 2 x 2 cell pattern. How- altitude airphotos. The NAPP series re- ever, since nearest neighbor resampling places the NHAP series. (See also: does not mathematically compute the new NHAP.) cell’s value, it is the only suitable choice NASA: National Aeronautics and Space Ad- for rasters that are not mathematically

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continuous such as land cover maps. With ground control points. such maps, mathematical resampling (like A topographic map that has been scanned bilinear, or cubic convolution) is totally (but not yet calibrated) is another ex- incorrect since mean values cannot be ample of a nominal image map. Simi- computed. larly, using TNTmips to mosaic airslides neatline: A cartographic term that means or airvideo images that cover the area of the border drawn around the perimeter of a 7.5' map provides a nominal image map. an object. (By contrast, rectifying and assembling nested folders: A set of folders within each these source images yields an image map, other. since that process used ground control points in some map coordinates.) (See Network Analysis: A process that deter- also: image map.) mines the optimal path between two points with any number of stops and route non-interlaced video: Video signal for- control parameters taken into consider- mats used in some display boards and ation (route mode). You can also locate monitors. A non-interlaced video dis- centers (points) and identify the linear play board refreshes the whole display components of the network that should every 1/60 of a second. It does not feed that center or that the center should intersplice fields but paints each succes- service (allocate mode). Both modes use sive line from top to bottom of the the characteristics of the lines and nodes screen. in the network. normalized contrast: See: contrast. NGA: National Geospatial-Intelligence Normalized Difference: See: ND Agency (formerly NIMA). normalized histogram: A histogram whose NHAP: National High Altitude Photography distribution has been adjusted so as to program. NHAP was coordinated by USGS have as close to a normalized (bell- and operated from 1980-1989 to provide shaped) distribution as possible. The data a publicly available collection of black and value that occurs most frequently will be white and CIR airphotos covering the near the center of the histogram. conterminous United States. The pro- Multimodal histograms are those which gram was renamed NAPP in 1987. have two or more significant peaks in NIMA: National Imagery and Mapping their distribution and cannot usually be Agency (formerly DMA, now NGA). satisfactorily normalized. nibble: A data element made up of 4-bits and northing: A rectangular (x,y) coordinate having 16 possible values. Nibbles are measurement of distance north from an stored two to a byte. east-west reference line, usually the equator or other parallel used as the axis of NOAA: National Oceanographic and Atmo- origin for a map zone or projection. False spheric Administration. northing is an adjustment constant added node element: A vector element required to coordinate values to eliminate nega- for topology that has no attributes ex- tive numbers. cept position; nodes occur at the ends of NRCS: National Resources Conservation all lines and at all line intersections if the Service. A service of the United States vector object has polygonal topology. Department of Agriculture to provide nominal image map: A preliminary map leadership in a partnership effort to help form that approximates an image map people conserve, maintain, and improve and that can usually be prepared using fully our natural resources and environment. automated procedures. For example, Formerly SCS. TNTmips can automatically extract a 7.5' NTSC video: National Television System nominal image map from Landsat or SPOT Committee video. The standard format satellite images using the positional and used by all American home video equip- angular properties provided with the im- ment (like VCR recorders and television ages. However, to convert it to an accu- sets). All the necessary color informa- rate image map, the user must introduce

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tion is encoded in a single interlaced sig- of magnetic tape in standard format. nal which is often called composite color operand: A parameter that designates a ras- video. ter object’s identification and location in null value: The absence of a value in a ras- a raster algebra expression. ter object. Null values often occur when operator: The function in a raster algebra a raster is extracted or resampled such expression that describes action upon a that the minimum bounding rectangle is raster object or the process by which ras- not coincident with the raster edges. Null ter objects, or operands, are to be com- values may also occur within the image. bined. Null is not the same as zero. optical disk: (historical term) A medium number of weighted runs: A type of infor computer file storage consisting of formation provided with a spectrum in a removable optical disk cartridges. Each Hyperspectral Analysis spectral library. side of a two-sided optical disk typically Each spectrum in the library is generated holds from 300 to 500 megabytes of data. in a laboratory and is actually the result These disks havbe been supplanted by CDs of multiple runs. The number of labora- and DVDs. tory runs is reported as the number of weighted runs. optimization: The process by which TNT- mips assigns display colors to the raster NWI: National Wetlands Inventory con- object cell values for display of multiple ducted by the USF&WS. raster objects for 8-bit (256-color) display modes. After TNTmips condenses the values, 4096 possible colors remain. Of the 256 colors that can be displayed — O — on an 8-bit display board, there is a standard set of 64 colors assigned to all raster objects, which are always “known” and object: An integrated, organized unit of data available for annotation and vector over- stored either in a TNTmips project file lays. The remaining 192 colors assigned or in an external, but attached file. These to the color map, are those that occur include raster, vector, database, and text most frequently in the RGB set of objects object types. being displayed. The colors in this RGB OCR: Optical Character Recognition. set that are not found in the 256-member ODBC: Open Database Connectivity is used color map are assigned to be displayed as to communicate with database manage- their closest match in the color map. This ment systems. process produces a very good natural color image on an 8-bit display board. OGC: Open GIS Consortium. option: An item on a menu. on-the-fly labels: Labels that are not stored as elements in a vector object but are option button: A type of button that opens generated during the display process us- an option menu. When a new selection is ing specified parameters. chosen from the option menu, the new selection is displayed as the button label. opaque color: When a new color feature completely masks out an earlier feature Oracle Spatial: A relational database man- in an image, the new feature is composed agement system from Oracle Corpora- of opaque color. For example, a poly- tion that includes spatial elements, which gon can be overlaid or drawn in opaque TNTmips can directly display as a shape color upon an image so as to completely object or import to a vector object. obliterate the original features in that orthoimage: An airphoto or satellite image portion of the image. that has been processed to remove per- open reel tape: (historical term) Medical spective distortions and so to have the images and satellite images from main- properties of an orthographic projection. frame and minicomputers were once Distortions of tilt and relief are removed commonly distributed on 12-inch reels

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so that all features in an orthoimage are OWS: Open GIS Consortium (OGC) Web in their true orthographic positions. Services. orthophoto: An airphoto that has been scanned, rectified, and reconstructed so as to represent its features in a map projection or at least in a flat rectangular — P — form without the usual distortions of geometry and perspective. Usually page layout: The process of selecting, siz- orthophotos are prepared from very high ing, and positioning multiple items to resolution stereo pairs. compose a page for printing. Also the outliers: Geodata points that lie far from result of this process. the regression line. Outliers can be legiti- PAL: Phase Alternating Line. A video stan- mate geodata points that show the ex- dard generally used by the rest of the treme variability of the geodata or they world outside the United States and can represent errors, such as incorrectly Canada that is not compatible with recorded geodata, an instrument malfunc- NTSC. tion, and so forth. Researchers drop outliers from statistical analyses when the pan: To move over an area of an image that outliers are shown to be errors because is larger than the on-screen viewing area. the outliers can skew statistical analyses. panchromatic image: An image collected outline font: A font in which each character in the broad visual wavelength range but is described by a set of lines or polygons rendered in black and white. The term rather than by individual pixels. Thus, has historically referred to a black and outline fonts can be rescaled to any size white photograph of a color scene. Since and displayed at any resolution with no the SPOT satellite 10-meter images are degradation of appearance. (See also: collected over this broad visual spectral bitmapped font.) band and are usually rendered in black and white, these images are called pan- outline highlight or location box: Shows chromatic. which menu selection or button in a window is the object of keyboard or mouse pane: A resizable subarea of a window con- focus. taining related options or components and set off from other areas of the win- out-of-gamut colors: Colors that are not dow by separators. The Tab key moves convertible to the “gamut” of colors the location box from pane to pane. displayable on a color monitor. Out-of- The arrow keys move the location box gamut colors may be encountered when from component to component within PhotoCD imagery is imported into TNT- one pane. mips. panel: A work area in a window composed overlay: (vector, CAD, shape, TIN) A largely of basic controls such as an array of but- transparent layer placed on an underlying tons and sliders. image. The overlay is where symbols, annotations, or image traces can be cre- panoramic: A type of view in which the ated or displayed without changing the viewer has an unobstructed view of an underlying image. A TNTmips symbol extensive area. overlay is a vector object with symbol parallax: The apparent change in relative shapes assigned to its nodes so that the positions of stationary objects caused by symbols line up with features of interest a change in viewing position. Parallax on the underlying image. For example, a displacements in overlapping images duck symbol might overlay a duck habitat only occur parallel to the line of flight. feature and be linked to a database record parallel: Two or more lines that are sepa- with site specifics. rated by the same distance at all points. overshoot: A line that extends beyond an in- Also a horizontal circle on the globe at a tersecting line where it was intended to constant latitude. end.

page 48 Glossary for Geospatial Analysis parallelepiped classifier or decision ing directories, seperated by a delimiting rule: A simple form of automated com- character, most commonly the slash "/" puter interpretation slightly more com- (as in Unix/Linux) or backslash character plex than boxcar interpretation. For par- "\" (as in Windows). allelepiped classification, the boundaries PC ARC/INFO: A vector-based Geographic between classes need not be rectangular Information System (GIS) developed and or parallel to the axes. A parallelepiped marketed by ESRI, Inc. area representing the location of each material sought is prism-shaped in the 2- PC ARC/INFO coverage file: pcARC/ , 3-, or n-dimensional distribution of the INFO’s legacy data directory for the 13 available multivariable images. (See also: different file types used to store the boxcar classifier) equivalent of a single TNTmips vector object. parallel port or parallel interface: A physical connection between a computer PCIPS: (historical term) A raster-based mi- and a peripheral device, such as a printer. crocomputer image processing system de- A parallel port uses a connection that veloped in the early 1990's and distrib- has more than eight wires. Eight of the uted by IBM. PCIPS was a menu-ori- wires simultaneously convey the eight ented entry-level system for systems with bits in a byte of data, while the remain- CGA and EGA video boards. ing lines control status information such PC-8: An 8-bit (256-character) IBM super as “send me more” and “stop sending.” set of the 7-bit ASCII character encoding Standard parallel ports in Windows are scheme that includes various symbols plus named LPT1, LPT2, and LPT3. Latin characters with diacritics. Printers parallel projection: A visualization of a and other output devices do not deal with three-dimensional object as a wireframe the upper 128 characters in a standard object in which parallel lines remain par- fashion. Thus, what looks like an “i” allel throughout the view. with two dots instead of one (ï, PC-8 character 139) on the screen may print as parallels: Circles on the earth’s surface, or something completely different. PC-8 lines on a map that are perpendicular to makes different assignments for codes the axis of the earth, and mark latitude 128-255 than does Latin-1, and thus is north or south of the Equator. not a proper subset of Unicode or ISO parent object: An independent prime ob- 10646. ject in a project file related to some other pen: One type of pointing device (some- prime object below it in the project file times called a “stylus”) used with an X-Y hierarchy. An object linked by Hyper- digitizing tablet. It has a pencil-like feel Index to some other objects is the par- which makes it ideal for free-hand draw- ent of those objects (referred to as its ing. (See also: pointing device, puck.) daughter objects). (See also: daughter object, HyperIndex, index area, link, pen plotter: An output device for line draw- stack.) ings that mechanically moves an ink pen over the drawing surface. Paris classification: An unsupervised classification or clustering process developed perceptual rendering: A rendering intent by Dr. Jack Paris and documented in: Jack that is best for photographic images when F. Paris and Helenann H. Kwong (1988) the destination gamut is narrower than Photogrammetric Engineering and Re- the source gamut. Perceptual rendering mote Sensing 54(8):1187–1193. Char- compresses the entire source gamut while acterization of Vegetation with Combined preserving the relationship between col- Thematic Mapper (TM) and Shuttle Im- ors. aging Radar (SIR-B) Image Data. peripheral device: A hardware device that is path: A description of the hierarchical chain not part of the computer, such as a of directories that define the logical lo- printer, scanner, or digitizer. cation of a file. A path specifies a loca- perspective projection: A visualization of tion using a string of characters signify- a three dimensional object in which par-

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allel lines converge towards a vanishing data bits each pixel represents. In 8-bit point. contexts, the pixel depth is 8, and each petabyte, Pbyte, or PB: A unit of computer display pixel can be one of 256 possible measurement for 250 (approximately) colors or shades of gray. With a 24-bit 1,000,000,000,000,000 bytes, raster (or with three coregistered 8-bit 1,000,000,000,000 kilobytes, rasters) the pixel depth is 24, and 1,000,000,000 megabytes, 1,000,000 16,777,216 colors are possible. gigabytes, or 1000 terabytes. (See also: planimeter: “An instrument for measur- bit, byte, exabyte, gigabyte, kilobyte, ing mechanically the area of plane fig- megabyte, terabyte.) Also petabyte. ures” (Random House). TNTmips con- photogrammetry: Obtaining precise mea- tains the electronic equivalent of a surements from images. planimeter; you use the mouse to draw around a shape on the display screen and photointerpretation: Analyzing, measur- TNTmips calculates and displays its area. ing, and categorizing chosen features from airphotos. planimetric map: A map designed to portray the horizontal positions of features; physiographic: Describing the characteris- vertical information is specifically ig- tics of a site’s physical geography. nored. picklist: A defined set of allowable attributes PNG: Portable Network Graphics. An image for a particular feature type that is pro- format for lossless compression devel- vided as a list. oped as a patent-free replacement for pictograph: A pictorial sign or symbol, for GIF. instance, representing a person with a point element: A single point defined by a stick figure. set of coordinates in space, and one of picture element or pixel: “The smallest the types of elements in a TNTmips vec- element of an image that can be individu- tor object. ally processed in a video display system” Vector elements may cross-index their (Random House). class attribute to a list containing the piecewise affine: A transformation method element drawing style, which may include for rectifying images that assumes each polygon fill pattern, point symbol, line control point is correctly positioned and width or symbol/point size, RGB color, then uses these points in groups of three RGB label color, RGB fill color, label font to transform an image by transforming number, label font size, label font zoom each triangular portion of the total im- factor, label font style, and label rota- age. tion angle. Pinyin: (literally, “spell sounds”) The pho- pointing device: A hand-held drawing tool netic alphabet based on Latin letters used with an X-Y digitizing tablet to reg- adopted in the People’s Republic of China ister coordinate data. This can be either in 1958 based on the Beijing/Mandarin a mouse-like puck or a pen. (See also: version of spoken Chinese. pen, puck) pixel or picture element: “The smallest point size: The vertical size of a text font element of an image that can be individu- is expressed in points. There are 72 points ally processed in a video display system” in an inch, so a 12-point font would be (Random House). The text and images 12/72, or 1/6 of an inch tall, while a 36- on a computer display are created by com- point font would be 36/72, or 1/2 inch binations of individual dots (pixels). Dif- tall. Of course the heights of different ferent display hardware allows for more letters vary (‘L’ is taller than ‘e’). The or fewer pixels on the screen, determin- point size refers to the distance between ing the display resolution that is possible. the highest ascender in a font’s charac- The more rows and columns of pixels, ter encoding scheme (the part above the the finer the image detail that can be re- line in a letter like ‘l’ or ‘b’), and the solved. lowest descender in the set (the part be- pixel depth or color depth: The number of low the line in a letter like ‘g’ or ‘y’). page 50 Glossary for Geospatial Analysis

(See also: bitmapped font, outline font) project file objects with which a TNT- polygon element: A type of element in a mips user works: raster, vector, CAD or TNTmips vector object. A polygon is database. (See also: project file.) defined by a list of line elements stored Prime Meridian: The meridian on the elsewhere, which can be retrieved and as- earth’s surface from which longitude is sembled to form a closed shape. measured; generally the meridian of Vector elements may cross-index their Greenwich, England. This meridian di- class attribute to a list containing the vides the earth into eastern and western element drawing style, which may include hemispheres. polygon fill pattern, point symbol, line principal components: A statistical tech- width or symbol/point size, RGB color, nique for reducing an image’s dimension- RGB label color, RGB fill color, label font ality. Principal components chooses number, label font size, label font zoom uncorrelated linear combinations of a set factor, label font style, and label rota- of rasters in such a way that each succes- tion angle. sively extracted linear combination, popup menu: A hidden menu that opens by called a principal component, has a pressing a mouse button, usually in some smaller variance. If the rasters have sig- specific area of the display, such as over nificant linear intercorrelations, the first the background. The system gives no few components will account for a large visual clues that indicate the presence of part of the total variance. a popup menu. principal point: (photogrammetry) The port: A physical and logical interface for a foot of the perpendicular from the inte- connection device between a computer rior perspective center to the plane of a and another component (such as a printer photograph. The principal point is physi- or a modem). cally located at the center of the photo- ® graph by intersecting the lines that con- PostScript : A standard page-description nect opposite fiducial marks. language for sending image information from a computer to a printer. PostScript printel: The smallest element a printer can was created by Adobe Systems, Inc., and print, or a single “dot” on a printed page. is used in many computerized phototype- The printed equivalent of a pixel. setting systems. print-file: A file created from a TNT page pour point: (watershed analysis) The low layout that includes all information nec- point on the boundary ridge between two essary for a designated printer to print neighboring watersheds. It is the point the file. Unlike print-rasters, print-files through which water from one watershed are not viewable in the TNT diaplay pro- would begin spilling over into its neigh- cess. Print-files created using the TNT bor if it were completely filled. print drivers are actually a pair of files: one with the name you assign and a .prf precomputed: An object saved in the for- extension (small file), the other with the mat in which it will be viewed, such as a name you assign and a .p1 extension (large tileset. file). If the layout is printed with TNT prerendered: An object saved in the for- drivers and covers multiple pages, there mat in which it will be viewed, such as a will also be a *.p2 file and so on. There is tileset. just one *.prf file regardless of the num- primary key: An important field within a ber of pages. Print-files created using the database record. Each table may have Windows printer driver have a .prn ex- only one primary key. Designation as a tension and there is only one print-file primary key requires that all records have regardless of the number of pages. Print- an entry for the field and that each files are supported on the Macintosh but record’s entry for this field be unique. only using TNT printer drivers. (See also: database object, field, foreign You may want to create print-files when key, record, table.) you will be printing at a later time par- primary object: One of the basic types of ticularly if the printer is attached to a

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machine that does not have TNT installed. raster object for both the processing ras- Print-files can be printed from within ter object and your reference on the dis- TNT (Main/Print From/Print-File) or by play. In a more complex case, you use copying the file to the port for the printer one raster object for the display image, designated when the print-file was cre- and a whole set of raster objects for pro- ated. cessing. (The processing set may include print-raster object: A raster that contains a the display raster.) For instance, you could dot-by-dot representation of a color print use a raster object with a composite natu- page that is viewable and can be manipu- ral-color image of the study site for the lated in the TNT products like any other display, while using the seven raster ob- raster object. Print rasters are either 4- jects containing the spectral bands of the bit (dithered) or 24-bit (undithered). Each Landsat Thematic Mapper data for pro- cell in a dithered print-raster object is a cessing. (See also: reference image.) nibble (1/2 a byte or 4 bits), which can profile: XY plot of values, such as eleva- specify 16 data levels. The 8 values cur- tion / distance. rently used define one color composite profile format files: These files tell print- dot on the printed page. Printers create ers, monitors, and other hardware devices each color composite dot from dots of how to provide sRGB colors. Profile for- cyan, magenta, and yellow (and possibly mat files go by two names: ICC on the black) or red, green, and blue (and possi- Macintosh and ICM on WIndows plat- bly black). Combinations of the three forms. colors together with black and white are specified by each nibble’s 8 possible data Project File: TNTmips’ integrated data levels. structure for large, user-defined collections of objects and subobjects. This You may want to create print rasters when single structure allows for the creation you are planning additional modifications and manipulation of rasters, vectors, da- of the raster or you want to be able to tabase files, and text files. A Project File view it before printing. You specify the is a single, conventional Windows, desired printer at the time you print a Macintosh, Linux, or Unix file that may print raster (Main/Print From/Print-Ras- be as large as 4 gigabytes for Windows 98 ter). and XP, and up to 16 terabytes for newer probability: “A statistical description of the operating systems. relative possibility that an event will oc- projection or map projection: “A device cur. Probability is expressed as a ratio of for representing all or part of a rounded the number of actual occurrences to the surface on a flat sheet. Since this cannot total number of possible occurrences” be done without distortion, the cartogra- (Random House). pher must choose the map characteristic processing mask: You define a processing [area, shape, scale, direction] which is to mask in the Feature Map process to iden- be shown accurately at the expense of tify which portions of an image to in- others.” Map Projections Used by the U. clude in the Feature Mapping analysis, and S. Geological Survey, Geological Survey which to exclude. The processing mask Bulletin 1532, Second Edition, U. S. Gov- can be as complex as you like. For in- ernment Printing Office, Washington, D. stance, you can outline an irregular area C. , 1982, p. 5. in an airphoto to include, but exclude lake Every process that establishes or trans- surfaces in that area, and yet include is- lates map projections offers the same lands in the lakes. (See also: mask) standard selection list of projections. processing raster(s): TNTmips image in- The practical choice of map projections terpretation processes can use either a for ungeoreferenced project materials is single raster object or a set of raster ob- normally determined by the kind of projects. That is, you can use one raster jection used by those project materials object for the display, and another raster that are calibrated to a projection. For object or set of raster objects for process- example, if you have a scanned USGS ing. In the simplest case, you use the same

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topo map in the polyconic projection, (See also: toggle button.) you may decide to calibrate satellite images and vector overlays (or translate existing calibration) to the same projection. (See also: ellipsoid.) — Q — prompt: A screen display, such as a blinking underline or a question mark that may be quad, quadrangle, map quad or map quad- accompanied by a beep, indicating the rangle: The geographic area covered by need for a keyboard response by the user. a map. One kind of map quadrangle is the prototype or training set: Sample cells in 7.5' x 7.5' area that is covered by a stan- an image known to represent a feature dard USGS 7.5' topographic map. Refer- type or ground cover of interest that you ring to a 7.5' map quadrangle does not define from ground visitation, detailed imply the presence of an actual paper airphoto interpretation, or other per- map. The term may simply designate sonal experience. the area covered by electronically stored prototype cell or training cell: One materials. sample cell that you select as belonging quadkey: Short for quadtree key. This term to a feature type. May also be called a is used by Microsoft in connection with “training cell.” Bing Map tilesets to index the positions proximity map: A map that shows the dis- of individual tiles. tance from selected features by gradient Quadratic BSpline: A curved smoothing shades of color. TNTmips can produce a that can be applied to a line. A BSpline is “distance raster” that shows distances calculated by a polynomial equation. Dif- from vector elements. Cells that are close ferent types of BSplines, such as Cubic to the vector elements have low values, BSpline and Quadratic BSpline, can be cal- and cells that are farther away have culated from different types of polyno- higher values. When displayed such ras- mial equations. ter objects show greater distances with quadtree: A method of representing two-di- greater display intensities. mensional space by recursively breaking pseudo-color image: A color image that a square of space into four squares half its does not directly render the colors of the size, which are made its children in a tree original image from individual red, green, data structure. and blue color values. A pseudo-color quantization: Dividing a continuous range image could result from such processes into a finite set of discrete values called as assigning colors to the gray levels in a quantization levels. If too few quantiza- grayscale image or assigning colors to a tion levels are used, false contours may cluster map. A color map pairs a display appear in an image. Quantization levels color with each possible cell value in a are often referred to as “gray levels,” but pseudo-color image. (See also: compos- the concept can also apply to color im- ite color raster object.) ages. puck: One type of pointing device (some- query: A query, or database query, is a set of times called a “cursor”) used with an X- instructions defining attribute criteria that Y digitizing tablet. It has a crosshairs are used to select records from a database. lens which allows for precise placement The specific spatial elements (such as of digitized points. (See also: pen, point- lines or polygons) to which those records ing device) are attached are then automatically se- pulldown menu: A menu that opens under lected for the current process. a menu title on the menu bar. push button: Button that starts the operation indicated by the button’s label. A push button cannot be left “on” or “off.”

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raster object is a raster that is stored in an RVC project file. raster algebra: Manipulations and func- — R — tions that operate on raster objects cell by cell. Any raster object can be used as radar image: An image composed of many a variable, or operand, in a raster alge- pixels, each of which represents the radar braic expression. You just set up a com- back scatter for that area on the ground. bination of operands in an equation and Darker areas have less back scatter than then assign a raster object to each oper- brighter areas. Bright features in an im- and. The result of the operation is stored age are those that return a large fraction in a new raster object. of the radar energy to the sensor, while raster cell: One value in a raster. If the dark features reflect little or no energy to raster contains geodata, such as an image the sensor. or elevation surface, each raster cell cor- radiance: “Radiant brightness or light: the responds to one specific area on the radiance of the tropical sun” (Random ground. A raster cell value may be the House). elevation above sea level at one position in a survey site or the intensity of red radio button: A type of toggle button in a radiation for a pixel in a video image. group of toggle buttons where only one of the toggle buttons can be on at a time. For convenience, a raster cell is usually thought of as square or rectangular, al- A radio button is preceded by a graphic though many image collection devices indicator of the state of the button. actually measure circular or elliptical ar- RAM: Random Access Memory. Read/write eas. memory for programs and data that the raster space: The area of a raster object computer uses as a general work area. The stored in an RVC Project File. This area more RAM in a computer, the more general work space it has and the larger the can be very large, up to 2,000,000,000 by 2,000,000,000 cells. projects it can handle. RDBMS: A Relational Database Management RAM disk: RAM that is reconfigured to work System has data organized in tables that like a very high speed disk drive. can be related to each other using pri- The system uses a RAM disk just as it does mary/foreign keys. any other disk drive. But since a RAM record: A database in TNTmips is organized disk is not a true magnetic storage device, its contents are lost when the computer is into tables, which contain records. Each rebooted. Any permanent files must be record supplies information gathered for an individual example. Records contain copied from a RAM disk to permanent one or more fields related to the topic of storage before turning off or rebooting the table in which they are found. For the computer. instance, the Crow Butte soil polygon range extraction: A method of converting database has a table of crop potentials, a grayscale raster object into a binary ver- and there is a record for each soil type. sion. In range extraction, two boundary (See also: database, field, table.) values are selected to bracket the desired rectification: Removing geometric distor- range of grayscale values. Everything tion from a raster or a vector object. above and below the boundary values is Rectification is usually achieved by align- set to 0 (black), while everything between ing raster features or vector coordinate the boundary values is set to 1 (white). positions with features in a base map or raster or raster object: A single, related, other coordinate reference framework. two dimensionally grouped set of num- Rectification may be used to bring sev- bers of a single data type. Each number eral distorted image segments into a com- represents the value of some parameter. mon framework so they can be combined Its position in the group represents its into a larger image. relative position to the other values. A reference image: An image on the display

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used for visual reference that is gener- dering intent in which an exact color ated by (or otherwise corresponds to) a match is required in everything but bright- raster object or set of raster objects. For ness, which may be modified so that the instance, TNTmips image interpretation range of brightness matches that of the processes can use either a single raster destination gamut. The source white is object or a set of raster objects. That is, transformed into the destination white, you can use one raster object for the dis- and all other colors are shifted accord- play, and another raster object or set of ingly. raster objects for processing. In the simplest case, you use the same raster relief: (as in shaded relief) The variation in object for both the processing raster ob- a raster object’s values that shows differ- ject and your reference on the display. ences between a surface’s higher and lower In a more complex case, you use one parts in elevation and slope. raster object for the display image, and a render: Create an electronic or hardcopy whole set of raster objects for process- representation, particularly of an outline ing. (The processing set may include the font. When an outline font is rendered, display raster.) For instance, you could it assumes a fixed size and shear angle on use a raster object with a composite natu- the screen, raster, or hardcopy to which ral-color image of the study site for the it is rendered. display, while using the seven raster ob- rendering intent: Determination of how to jects containing the spectral bands of the handle colors that are available in the Landsat Thematic Mapper data for pro- source image that are not available for cessing. (See also: processing rasters.) printing from the following choices: ab- region: A simple object used to define a com- solute colorimetric, relative colorimet- plex geographic area of interest. Re- ric, perceptual, and saturation. gions have rudimentary topology in that reproject: To change an object from one map alternating nested polygons are inside projection to another. In the TNT prod- then outside the region. Regions pro- ucts, reprojection can be done on-the-fly vide sophisticated and powerful selection in the Display Spatial Data process, or it capabilities for analytical tasks. can be used to create a new object with region of interest: (Feature Mapping) De- the desired projection using the resam- fines the area of the input raster objects pling or warping processes. to be considered for all subsequent pro- resample: To interpolate cell values in a cessing while that region is selected. A raster object and create a raster with larger selected region of interest affects the cat- or smaller cells. TNTmips resamples ras- egories that can be defined, limits the ters “on-the-fly” to change their scale or area in which cells that satisfy the deci- orientation for display purposes. The sion rule are searched for, and defines means to save raster objects with changed the region of the feature mapped raster scale, orientation, or geometric propor- for which measurements are tabulated in tions is also provided. (See also: interpo- Feature Mapping’s statistical report. Fea- lation.) ture marking is also limited to the region of interest. (See: categories, feature map- residual: The difference between a value ping.) computed by a model and the value entered by a user such as is found in the registration: Geometrically aligning sets Georeference process. of image data such that corresponding features are coincident. (See also: resize: To change the height and/or width of coregistration.) a window. regression line: A line that best describes resolution: The level of object detail or all the data points using a particular sharpness determined by how many pic- method of error estimation, such as least ture elements compose an area of a dis- squares. play or corresponding raster. Resolution may refer to sensors, raster objects, or relative colorimetric rendering: A ren- displays. Low resolution display devices

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produce images with a grainy visual tex- then substitutes a fourth coextensive ras- ture. High resolution displays use such ter object for the intensity component small picture elements that they can pro- before conversion back to RGB compo- duce a near-photographic quality image. nents for display. The object selected for (See also: ground resolution.) the intensity component is generally of higher resolution than the objects selected resolution: (digitizer) The smallest move- for the RGB components and imparts a ment that can be detected by the digi- higher pseudo-resolution to the displayed tizer. Resolution is usually expressed in image. (See also: HIS, RGB.) either measurement units (.001") or dots- per-inch (1000 dpi). RGB set: A set of coregistered, coextensive rasters that represent the red, green, and restitution: The determination of the true blue bands of an image. (map) position of objects or points; the image appears distorted or displaced on RGB video: A video image composed of unprocessed aerial photographs. Restitu- separate red, green, and blue signals. RGB tion corrects for displacement resulting video is a general term that applies to from both tilt and relief displacement. different technologies (analog or digital) Restitution in classic photogrammetry is and standards (like TTL and RS-170). commonly achieved by analytical meth- RMBM: right mouse button menu. ods or through the use of stereoscopic root table: A table at the root of the hierar- plotting instruments. The chical database tree (left-most side of the orthorectification processing step in tree) in the Database Editor. TNTmips applies elevation information from an elevation raster object to an im- root window: The main window of the X age to produce an orthoimage output ras- server in X desktop mode. Each client ter object. process runs as a subwindow within the root window. On Windows systems, you RGB: Red, Green, and Blue. The red-green- can choose to display the MicroImages blue color model uses position within a X Server title bar if desired. Besides iden- cube to describe colors. The axes of the tifying the MicroImages X Server, this cube are the red, green, and blue values. title bar provides access to preferences, The shades of gray are found along the the overview window, the X server ver- diagonal from the origin of the cube, where sion number, and MicroImages’ techni- red, green, and blue values are zero and cal support email address the apparent color is black, to the opposite corner, which appears white (red, row: A horizontal list of data values or dis- green, and blue values are 100%). RGB is play cells in a raster object or display. generally used in reference to the sepa- RPC: Rational Polynomial Coefficient used rated spectral bands of an image so that for producing an orthorectified satellite the red, green, and blue bands taken to- image. gether create a natural color image. (See RS-170 video: An historical standard for also: HBS, HIS.) RGB analog video in the USA that gov- RGBB: A display method that converts an erns the form of the RGB color signals. RGB raster set into an HBS raster set and RS-170 video has a 15.7 kHz horizontal then substitutes a fourth coextensive ras- scan rate and a 30-cycle per-second frame ter object for the brightness component rate. It is not modulated with a carrier as before conversion back to RGB compo- is broadcast video. nents for display. The object selected for rubbersheeting: Any process in which a the brightness component is generally of raster is stretched differentially to match higher resolution than the objects selected a new set of geometric constraints. This for the RGB components and imparts a shape change could be defined by any higher pseudo-resolution to the displayed one of many transformations such as image. (See also: HBS, RGB.) changing a map projection, trilateration RGBI: A display method that converts an to change the absolute position of cells RGB raster set into an HIS raster set and within a raster, fitting a polynomial to a

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surface, least squares movement of con- many of the returned echoes are focused trol cells, and so on. on a single point effectively increasing run-length encoding: A compression the length of the antenna that is imaging method for raster data stored by row with on that point. Very precise knowledge of two or more adjacent cells being recorded the relative motion between the sensor as a single value and its run (number of platform and the imaged objects is re- cells with that value). quired. RVC file: Raster/Vector/CAD formatted sash: A small graphic control component on file. The extension for the TNTmips the separator between two panes. A sash format for Project Files is .RVC. These moves the separator to change the size files incorporate the benefits of a 32-bit of the panes. Drag the sash with the compiler. (See also: Project File.) mouse to make a pane larger or smaller. RVF file: Raster/Vector Format(ted) file. saturation: One of the three coordinates The DOS extension for all MIPS (v3.3 that the HBS and HIS color domains use and earlier) Project Files was .RVF. to define a display color. Saturation designates how far away a color is from a gray or neutral color of equal intensity. (See also: HBS, HIS.) saturation rendering: A rendering intent — S — in which the original colors are modified to exactly fill the destination gamut while samples: Groups of cells in an image se- preserving the saturation of the colors lected to represent one feature type or such that some parts of the color space land cover of interest. You define samples are expanded and others are compressed. from your knowledge of the site. (See No other rendering method can expand a also: prototypes, training sets.) narrow gamut to be wider. sample set: For unsupervised classification scalar: An SML variable for numeric values. processes, a set of sample cells that is The SML naming conventions presume selected from the input raster set and any variable that begins with a lower case used to automatically define classes. The letter is a scalar value or a string. selection of the sample set during pro- scale bar: A map component that shows the cessing is controlled by a sampling inter- map scale graphically. Also called a sta- val (in line and column directions). dia bar. sampling: The process of approximating scale-lock: A GeoLock option; adjusting the an image using a subselection of pixels. Sampling is usually done at constant in- map scale of one View window in a set of tervals though this is not required. Gen- open View windows changes to the new map scale all View windows for which you erally, as the number of samples increases, set up scale-locking. the quality of the image increases. (See also: resample.) scale value: A number used as a multiplier to translate a set of numbers from one range SAR: Synthetic Aperture Radar. SAR uses a of values into another. For example, a microwave instrument that sends pulsed signals at targets and processes the reset of decimal values that range between turn signals that it receives. The SAR 0 and 2 could be projected into the numeric range of 0 to 100 by multiplying sensor can function day or night and re- each number in the set by a scale value of gardless of weather conditions. SAR dif- 50. fers from other radar imaging processes because it synthesizes a greater antenna scanner: A digitizer that produces an image length than actually exists. Signals re- (raster object) from flat input material ceived and recorded by the radar system such as photographs, maps, and drawings. as it moves along its flight path are Dop- scatterplot: A graph of point geodata. pler-shifted. By comparing the Doppler script: An uncompiled program written with frequencies to a reference frequency,

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SML. A script may define styles, create a that forms part or all of a glyph. A glyph new display layer, perform custom pro- made from polygons will be filled when cessing, or a define a tool or macro. printed but may optionally be displayed scroll: “To move the current text or image in outline form. A glyph made of line up, down, or across the monitor so that segments rather than polygons is known new text or image appears on one edge of as a stroke font. It is faster for the com- the screen as it disappears from the other” puter to draw a stroke font than a font (Random House). Scrolling is controlled made of polygons. in TNTmips with the mouse and the ar- select: To choose objects or element types row keys. For example, a list of objects for display or other operations. in a project file which is too long to fit on select button: The mouse button used to the text screen can be scrolled up and make a selection. TNTmips assigns the down with the vertical arrow keys. select function to mouse button one, scroll bar: Indicates position of current view which is generally the left mouse button in relation to the whole, and used to change unless you have reconfigured your mouse the user’s viewpoint. The scroll bar con- setup. sists of a slider, scroll area (“trough”), selection box: (more properly called the and scroll arrows. location box) A graphical symbol that SCS: Soil Conservation Service. A service of marks the current location of keyboard the United States Department of Agricul- focus for an operation. Moved with Tab ture. Now called the NRCS. and arrow keys. SCSI port: Small Computer Systems Inter- selection highlight: An item displayed in face (SCSI is pronounced “skuzzy”). A reverse video in a text list, that indicates physical connection between a computer which member of the list is selected. You and a peripheral device, such as an exter- complete the selection by pressing the nal hard drive or optical drive. Now largely key (or double clicking with the supplanted by USB connectors. left mouse button). seam: The junction in the area of overlap selection query: (in database queries) A between raster objects combined by tiling selection query is constructed from one or mosaicking in TNTmips. or more comparison expressions. Only SECAM: Sequential Couleur à Memoire. A if the entire query evaluates to “true” video standard used in France and the (non-zero) for an element, is the ele- former USSR. ment included. sections of land: The U.S. Public Land Sys- selection set: All elements currently se- tem divided much of the U.S. into square lected by the Element Selection tool for sections of land with an area of approxi- viewing or editing make up the selection mately 1 square mile (sides 1 mile long). set. One element in the selection set, Since most of this survey was completed generally the last element selected, is the in the late 1800s, these sections vary active element. Attribute assignments greatly in area and shape. In some areas and editing changes can be applied to just survey adjustments have created sections the active element or to all elements in as big as 2 square miles. Sections are the the selection set. (See also active ele- basic unit of land ownership in the central ment.) and western U.S. They are usually bounded semivariance: Statistic that compares ad- by roads that give rise to the checker- jacent cells and calculates their related- board land patterns characteristic of these ness. areas. semivariogram: Plot of semivariance val- seed point: (watershed analysis) Any speci- ues. fied point in the landscape used to deter- separator: A dividing line that marks a logi- mine the upslope area (basin) that drains cal division between areas of a window or to that point. menu. segment: A segment is a line or polygon serial port: A physical connection between

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a computer and a peripheral device, such slider: A graphic control component that as a plotter. The eight bits in a byte are controls the setting of a variable. Move transmitted serially, or end to end, the slider by dragging it with the mouse to through a single line while the remaining make its associated value larger or smaller. lines contain status information such as sliver polygon: A polygon with a very high “send me more” and “stop sending.” perimeter to area ratio or simply very Windows standard serial ports are named small area. Such polygons are often COM1 and COM2. formed when vector objects are merged. serpentine order: A grid cell numbering slope: A measure of how steeply a surface or scheme found in the Polygon Grid analy- line inclines. Slope is computed by divid- sis process. When a user selects the Ser- ing a line’s vertical rise or fall by the dis- pentine Order scheme, the sequential tance the line travels on the surface (the numbering proceeds from the lower left “rise over the run”)—usually expressed cell upward to the top of the first col- as a percent. umn; numbering then proceeds downward through the second column, and so forth. smart line following: An interactive process for converting raster line images to shaded relief: See: relief. line elements in a vector object. The shapefile: a popular geospatial vector data user clicks on a line image, and the pro- format developed by ESRI that can be cess follows the line, over-tracing a vec- used by a number of different software tor line. The process stops at the edge of products. Shapefiles contain only one the raster, at the end of the line, or at a element type and have only one attribute spaghetti junction of lines that the user table, which has an implied one-to-one must guide it across. attachment type. A shapefile is actually SML: Spatial Manipulation Language. A pro- a collection of same-named files with dif- gramming language for manipulation of ferent extensions, some of which are re- the geospatial objects in the TNT prod- quired and some are optional. The file ucts. SML allows you to enter either im- with the spatial elements has a *.shp ex- mediate commands or to write a full pro- tension. The other required files are the gram. To use SML interactively, you en- index file (*.shx) and a database file ter single commands from the keyboard (*.dbf). and SML executes each command as it is shape object: A coordinate data object with entered. To use structured programs with no topology used for direct display of SML, you prepare a script ahead of time. ESRI shapefiles and Oracle Spatial lay- soil association: A soil mapping unit con- ers. taining adjacent soils, but the survey did shear: Angular slant given to a vector font not take the time and effort to delineate to produce the effect of italics. them. Soil association information is suit- shift sequence: A keyboard technique for able for general planning only: to com- text entry in a language that uses more pare areas, to locate refuge tracts, and than one character set, such as Japanese certain kinds of land use. which uses a mix of ideographs, Latin soil complex: A soil mapping unit with two characters, and Japanese phonetic char- or more soils so intricately mixed that acters. The user enters a shift sequence they cannot be shown separately on the to switch from one character encoding map. scheme to another. Electronically, each soil group: (undifferentiated) A soil map- character is preceded by a shift sequence ping unit with two or more soils. For the byte that identifies its character set. purposes of the map, there was little value slant range: The distance measured along in separating them. a line between the radar antenna and each soil mapping unit: An area on a soil map target (that is, each reflecting point in with a complete, closed border drawn by a the illuminated scene). The measure- soil scientist, usually representing an area ment is perpendicular to the line of flight. of one type of soil. A mapping unit is nearly equivalent to a soil phase with the page 59 Glossary for Geospatial Analysis

exception of small scattered bits of other electromagnetic spectrum. (See also: soils that are not worth showing. color-infrared, electromagnetic spec- soil phase: A subset of a soil series differen- trum.) tiated by slope, stoniness, or other char- spherical web mercator: Google and acteristics that affect the soil’s usefulness. Microsoft tilesets structures were de- soil profile: The sequence of natural layers, signed for global coverage using a spheri- or horizons, in a soil. A profile extends cal adaptation of the Mercator projec- from the surface down into the parent tion called the Spherical Web Mercator material that has not been changed much (EPSG code 3785). Google Earth and by leaching or by the action of plant roots. NASA World Wind tilesets use Plate Car- rée (Equirectangular). TNTmips tilesets soil series: A U.S. category of soil classifi- can use any projection and datum de- cation including soils that have similar fined by EPSG and projections defined profiles (thickness, arrangement) named by other sources. for a town or geographic feature near its first observation. Soils in a series are es- spheroid: Any shape that closely resembles sentially alike in characteristics that af- or approximates a perfect sphere. In fect their behavior in an undisturbed land- the context of map projections, a spher- scape. oid is an ellipsoid of rotation that is flattened at the poles, like the earth. solid modeling: The process of rendering a 3D surface from vector type data. This spline: An interpolating polynomial for a process is widely used in CAD software set of coordinate points used to fit a curve packages to prepare a realistic color pre- that connects the points. (See also: Bézier sentation of a component part, a build- curve) ing, or other solid object from complex SPOT: The French Systeme Probatoire vector-oriented engineering drawings. In d’Observation de la Terre from Spot GIS vector-oriented software, contours of Image S.A. SPOT 1 was launched in 1986 the surface of the land stored as vectors The SPOT 5 satellite, launched in 2002, might be used to render a solid model of provides panchromatic images with syn- the land’s surface. thetic 2.5 meter resolution. They can be spaghetti digitizing: Entering line data in color-enhanced with SPOT 10-meter no particular order using a digitizer. color images. SPOT satellites may be pointed at an angle off-axis or off-nadir SPANS: The SPatial ANalysis System from to collect forward and rearward images: a TYDAC AG.. SPANS was developed and technique that yields stereoscopic image marketed in the 1990's. pairs from which accurate elevation ras- spatial: An adjective applied to objects that ters can be computed. vary in space in two or three dimensions. spread: The spread operation changes the Spatial Manipulation Language: See: SML colors between two selected tiles in the speckle: The image noise typically found in Color Map Editor window. TNTmips radar images. Radar images with speckle takes the colors in the starting and end- have a grainy appearance that comes from ing tiles and assigns even color grada- random variations in the strength of the tions to each tile between them. You back-scattered signal. can select different spread types to tell TNTmips which way to traverse the spectral band or spectral region: A well- color space between the endpoints. (See defined, continuous wavelength range in also: HBS, HIS, RGB.) the spectrum of reflected or radiated electromagnetic energy. Red, green, and blue sRGB: The standard color space developed are all spectral regions within the portion by Hewlett-Packard and Macintosh. of the spectrum that is visible to humans spur: A false line segment that extends a as light. Color-infrared images are com- short distance beyond a T-junction of posed of red, green, and a spectral region two lines. Binary raster thinning pro- commonly called the photoinfrared, cesses often leave spurs that should be which is not in the visible portion of the

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erased by raster editing before final the subdued natural tones of the underly- vectorization. ing image. SQL: Structured Query Language. An ANSI State Plane Coordinate System or SPCS: standard for accessing and manipulating The State Plane Coordinate System databases. (SPCS) defines map coordinates by zone stack: A hierarchical arrangement of im- for the United States. Each zone has one ages and other information used by central meridian and scale factor, which HyperIndex that graphically links logi- permits all USGS quadrangle maps in a cally related objects or files. A stack has zone to be mosaicked exactly. Zones with the inverted tree form of a genealogy greater north-south extent use the Trans- chart. (See also: HyperIndex, link.) verse Mercator projection, while those with greater east-west extent use Lam- stack profile: A series of profiles for visu- bert Conformal Conic. (The panhandle alizing a three-dimensional surface. The of Alaska is the only exception, and uses stack profile is saved as CAD object. Oblique Mercator). standard attribute tables: standard at- stepwise linear classification: A super- tributes can be calculated for geometric vised image processing routine applied in lines and polygons in Project File for- the same fashion as maximum likelihood mat and for line- and polygon-contain- classification using training sets, or pro- ing shapefiles that are directly used. The totypes. This method applies the classi- attributes calculated depend on the ele- cal techniques of stepwise linear discrimi- ment type. For example, length and the nant analysis to set up the classification center point for x, y, and z are deter- model and map the materials desired from mined for lines; and area, and the cen- the input raster objects. (See also: maxi- troid x, y, and z are determined for poly- mum likelihood classification) gons, among other properties. Standard attribute tables can be created and main- stereo elevation: An elevation surface de- tained in TNT’s Editor or created in a rived from stereo pairs of remote sensing separate TNT process (Geometric/At- imagery. For example the SPOT satellite tributes/Standard). can collect an “off nadir” image and then in a subsequent fly-over collect its coun- standard lossless: A raster compression terpart to make a stereo pair. The stereo method. The compressed output from elevation process takes the 3D effect of this method maintains 100 percent fi- that stereo pair to derive an accurate ras- delity to the colors of the uncompressed ter object of elevation values. input raster object. Standard Lossless is best for objects that have good pixel-to- stereo viewing: An elevation raster and an pixel correlation in the image. image overlay are combined to produce a 3D effect when viewed with a stereo view- standard parallel: A parallel of latitude ing device (e.g., anaglyph glasses). used as a control line in the computation of a map projection, and which is there- style query: (in database queries) A style fore, true to scale. Some map projec- query is constructed from a combination tions have no defined standard parallel, of comparison expressions, which exam- others have one, while others have two. ine values of element and database variables, and assignment statements, which standard 64 annotation colors: In 8-bit set the values of drawing variables. contexts the Color Palette Editor window normally reserves the first 64 col- stop: (also called a waypoint) an intermedi- ors for a standard set of user annotation ate point along a route that must be vis- colors for text and overlays. That leaves ited and is consequently included in your 192 colors for the image itself - ample network analysis. color space for representing most natu- Sub-extremum: A method for calculating ral color images to the human eye. The important points in the Irregular 3D 64 standard colors are chosen at fixed Points method of the Extract Important intervals in the RGB color model. They Points process. generally appear brighter and purer than

page 61 Glossary for Geospatial Analysis subobject: A component of a TNTmips each class as plus and minus one standard project file attached to a primary object. deviation from the mean of the values A subobject contains data that describes of the prototype, or sample, values se- some aspect of the primary object. Ex- lected to represent that class. This amples: 1) map registration information method has the advantage that like a is kept as a subobject (Regist) under the simple boxcar classifier, it is very fast to raster object it calibrates; 2) a pseudo- apply the resulting decision rule to the color table is kept as a subobject (ColMap) unknown pixel values. More informa- under the raster object it describes; 3) a tion on this process can be found in: H.L. HyperIndex subobject attached to a vec- Wagner and G.H. Suits (1980) Proceed- tor overlay polygon maintains the links ings of the 14th International Sympo- TNTmips uses to retrieve that polygon’s sium on Remote Sensing of the Environ- associated daughter objects. ment, vol. III pp. 1525–1529. Envi- subtractive color: Creating color by using ronmental Research Institute of Michi- absorption or scattering to selectively re- gan, Ann Arbor Michigan. A Low Cost move some of the colors of light, or ra- Classification Algorithm for Developing diation, reaching the human eye is a sub- Countries. tractive process. The use of pigments, supervised classification: A type of auto- such as color printing or a painting, dem- matic multi-spectral image interpretation onstrate this subtractive color process. in which the user supervises feature clas- The greater the number of different col- sification by setting up prototypes (colored pigments mixed together, the darker lections of sample points) for each fea- a pigmented object appears. This dark- ture, class, or land cover to be mapped. ness results from an increased absorption TNTmips statistically analyzes these col- of visible light by the pigments and, con- lections of points to characterize each sequently, less light reflected to the eye. feature and then maps them by math- The presence of fewer pigments or their ematical comparison. absence altogether results in greater re- surface fitting: Techniques that use 3-di- flectance of visible light. Selective ab- mensional vector point data to create a sorption removes a color(s) from the re- raster object containing an elevation sur- flected radiation and results in the per- face. Various methods can be used to fill ception of the complementary color. the gaps between the vector points and subwindow: An auxiliary window that opens derive the elevation values for the inter- as the result of some user action in the mediate raster cells. parent window (such as pressing a but- surface object: A raster object whose cell ton), or of some processing condition (a valuse are used as elevation values to de- dialog box subwindow might open with a fine a three-dimensional surface over message or warning.) which other objects can be draped. Suits’ Maximum Relative classification: SVG: Scalable Vector Graphics. A W3C stan- A supervised Auto-Classify method that dard for vector graphics based on XML. is computationally quicker than the other methods. The algorithm for this process S-video: Separate video. S-video maintains computes the composite brightness and the video in two separate signals: lumi- the ratio of each band brightness to the nance and color. composite brightness. The mean and stan- symbol hot spot: The place on a TNTmips dard deviation of each of these param- symbol that controls its position. TNT- eters is then calculated for a class and used mips locates a symbol by putting its hot to define the class boundaries. spot on the point that provides its coor- Suits-Wagner classification: A simple dinates. Every symbol has a hot spot: it form of supervised or semiautomatic clas- defaults to the center of the symbol de- sification that operates similarly to a box- sign area, but may be relocated. The hot car or parallelepiped classification. This spot is also called the origin. method defines the sides of the box for symbol overlay: A vector object can have symbol shapes assigned to some or all of

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its point features. When this vector ob- groups, such as a selection list, can be ject is displayed over (or overlaid on) an composed of multiple items through image, you can also choose to display which the location cursor can be moved the symbols over the top of the features by the arrow keys. in the underlying image. Such symbols table: A database is organized into tables that may also be attached to database records contain records. Tables cover different and used to graphically retrieve such ref- topics related to the same common theme. erence information. For example, a sym- The theme and its extent of development bol overlay that uses ducks to represent determine the number of tables that com- nesting sites could be shown over a habi- prise the database. For example, the Crow tat map. A click on a particular duck Butte soil polygon database contains symbol could retrieve a record from an twelve tables, in such areas as yield, crop associated database and display it on the potential, and statistical information. (See text screen to provide such information also: database object, field, record.) as the date of first occupancy, number of eggs, number of fledglings, and so on. tag: A temporary number that can be as- (See also: overlay.) signed to a class in the Training Set Edi- tor of the Auto-Classification process. For symmetric minima: A raster cell that has example, you import a set of classes into a value less than two opposite neighbors the Training Set Editor. Each class has a in any direction. A raster object of sym- value when it is imported. If a class does metric minima is calculated from an el- not have the value that you want to use, evation raster object and provides a rep- you can assign a tag number to the class. resentation of the relative roughness of You can assign different tag numbers to terrain. TNTmips includes symmetric as many different classes as you wish. minima and flats (see above) in the same When you assign the same tag number to output raster object. more than one class, the Training Set synthetic resolution: An apparent increase Editor merges the classes. in spatial resolution achieved either by tail: The portion of a distribution curve that resampling image rasters or by combin- has few values and extends away from the ing images from different sensors of vary- peak area of the curve where most values ing resolutions (such as SPOT panchro- are located. matic and TM multispectral). TARGA file: Truevision Advanced Raster system table: one of a few table types not Graphics Adapter file. The TGA format shown to the user by default. System supports color maps, alpha channel, tables include style assignment tables for gamma value, postage stamp image, tex- all geometric object types and internal tual information and developer-definable tables for vector, shape, and TIN ob- data. jects. Some raster object types also have an internal table. You can show system Tasseled Cap A transformation that rotates tables from the right mouse button menu four LANDSAT MSS bands such that the at the element level in a layer manager majority of information is contained in window (See also: internal tables.) two components or features that are directly related to physical scene characteristics, brightness and greenness. The tasseled cap transformation is used for agricultural crop monitoring. — T — TCP/IP: Transmission Control Protocol/In- ternet Protocol are low-level communi- tab group: (also, “Field”) A component of cation protocols that allow computers to a window such as a button, list, scroll bar, send and receive data. pane, sash, or slider (sometimes “scale”) template: A hardcopy layout with designated that can be selected with the location constant and changing layers and groups. box by pressing the Tab key. Some tab A template automatically prompts for re-

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placement layers for those designated as as soils, hydrology, and roads. changing when opened. theme map: A map that uses a color gradi- terabyte, Tbyte, or TB: A unit of measure- ent to illustrate the variation of a quan- ment for 240 (approximately) titative attribute, such as population or 1,000,000,000,000 bytes, 1,000,000,000 income. kilobytes, 1,000,000 megabytes, or 1000 Thiessen polygons: Polygons that bound gigabytes. (See also: bit, byte, exabyte, an area closest to the points that form gigabyte, kilobyte, megabyte, petabyte, the boundary than to any other points. exabyte, zettabyte, yottabyte.) TINs are more efficient than other data terrain: The elevation raster used to provide structures at generating Thiessen poly- surface values for a 3D simulation, such gons. They are also known as Voronoi as in TNTsim3D. diagrams. terrain tileset: A tileset designed for pre- thinning: (rasters) To remove cells from sentation of surface elevation informa- wide line images in a raster object. When tion particularly for 3D stereographic view- a scanner creates a raster object, the lines ing. in the drawing typically are several cells terrain scene: A rendering of geometric rep- wide in the result. Some automatic resentations of geographic entities upon vectorization techniques work on the a land surface in such a way as to simulate data after the line images in the raster the view of a human observer. (OpenGIS object have been thinned to make the Consortium) line images just one cell wide. Terra-Mar: An early vendor of a raster-based thinning: (vectors) Reducing the number microcomputer image processing and GIS of coordinate pairs that describe a system. vector’s line and polygon elements. Some of the coordinate pairs will be dis- text: A string of characters grouped in a file. carded when straight line lengths replace text cursor: A graphic mark such as a blink- curved or noisy segments in the original ing underscore, vertical line or character- lines. sized box on the screen that indicates the threshold: (binary) The separation point focus of keyboard text entry and editing. for converting grayscale raster cell data text field: A component of a window that into binary (black and white) data. For a can be selected with the location box for raster object scanned with 256 levels of textual information that can be entered gray, a threshold might be set at 180. and edited from the keyboard. Then the output binary raster object text monitor or text screen: (historical would have a 1 for every cell in the input term) In the old DOS MIPS (v3.3 and raster object that had the value 180 or earlier) The B/W or color monitor used higher, and 0 everywhere else. to display text materials (like menus, da- thresholding: Setting a data conversion tabase records, and keyboard input). MIPS separation limit such that any incoming used a second screen (the display moni- value above the designated limit, or tor) for images and maps. threshold, is assigned one value (in bi- text object: Anything from a simple string nary thresholding, a “1”) and any in- of ASCII characters to a more complex, coming value below or equal to the limit formatted page description. A text object is assigned another value (in binary may be output from some TNTmips pro- thresholding, a “0”). Thresholding can cess, reference information created by a be used to generate a binary raster from a text editor, or a file generated by a word 16-gray-level scan, or to find feature processing program. edges during the steps of raster to vector conversion. texture: The raster used as a surface drape in a 3D simulation, such as in TNTsim3D. tick mark: A line that sticks out or in along a map grid boundary that may also occur theme: The common property used to orga- internally at specified intervals. nize vector data into separate objects, such

page 64 Glossary for Geospatial Analysis tie point: A point that is co-located on two bers are encoded into the filename for raster objects that have an overlapping each tile file. In the hierarchical tileset geographic extent. Tie points are used structures created for use in Google Maps in the manual mosaic process to estab- and Bing Maps, tile files are named by lish the relationship between adjacent their tile column number and grouped in pieces of the mosaic that provide no ab- directories named for their tile row num- solute ground control information, but ber. do show some common ground feature tile format: The formats that can be used in in each piece. For example, multiple each type of tileset structure are dictated frames of airvideo can be tied together by the application that that will use the with tie points (farm buildings, field cor- tileset and the specific uses within that ners, bushes, rock outcroppings, bends in application. Although the allowed for- streams) even if the map coordinates are mats vary, Google, Bing Maps, and World not known for such features. Then, the Wind tilesets all support the use of JPEG map calibration for the entire sequence and PNG tile file formats. can be established from control points sparsely located in the mosaic sequence tile map: A tile map identifies which tiles are (such as road intersections) for which the available in the corresponding tileset. It map coordinates are known. (See also: lets you examine a tilesets spatial cover- control point.) age, assess its completeness, identify missing tiles, and view the file format of tiles. TIFF: Tag Image File Format. A series of A tile map is a series of TNT raster ob- image file formats designed to transfer jects, one for each zoom level in the tile- images between different software pack- set. Each tile map raster has one cell for ages. .TIF files are wildely used for each tileset tile. The cells are color-coded lossless 24-bit color images. to indicate the file format of the corre- TIGA: (historical term) Texas Instruments sponding tile file (green for JPEG, red for Graphics Architecture. An early soft- 8-bit PNG tiles, and yellow for 24-bit ware interface that standardized commu- PNG tiles). nication between application software tiles: Rectangular areas of defined size in a and display boards that used one of the raster object used for storage of the in- TMS340 chips. TIGA divided tasks be- formation. Storing raster objects in tiled tween the TMS340 display processor and format generally increases display speed the CPU of the host microcomputer to when viewing less than the entire object. improve performance and generalize display driver requirements. Also, raster object image pieces that are assembled and trimmed in the TNTmips TIGER files: topologically Integrated Geo- mosaic process or one of the other pro- graphic Encoding and Referencing files cesses on the Tileset menu. (See tilesets compiled and distributed by the U.S. Cen- for more on this use of the term.) sus Bureau. A third usage of the word tiles occurs in tile column and row numbers: tiles in the Color Map Editor where the upper Google Maps, Bing Maps, and World part of the window displays the colors in Wind tileset structures are aligned to a the map with small sample squares, or predetermined global grid at each zoom tiles. The active or selected tile is out- level. The position of each tile within lined in white, and its cell value and a the grid is indicated by its tile column larger sample is displayed below. number (east-west position) and tile row number (north-south position). Tile rows tileset: A multifile object in a predefined struc- are numbered from top to bottom and ture designed for very efficient viewing tile columns from left to right, each be- of geodata particularly over the Internet. ginning with 0 in the upper left corner of A tileset can range from a few tiles cover- the global grid. In tilesets using the Bing ing a local project to 100s of million tiles Maps flat quadkey structure and the World covering a continent or the globe. Wind structure, tile column and row num- TNTmips can generate tilesets in its own structure and in Google Maps, Google

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Earth, Bing Maps, and World Wind struc- each existing triangle and adds a new node tures. when it finds a point of high correlation. A tileset structure is the most efficient Then it recomputes the local topology way to store each image for use in a geo- and goes on to the next triangle. mashup. Its hierachical directory struc- TIN elements: TNTmips TIN objects con- ture and small compressed tiles, which are tain four element types: nodes, edges, precomputed at each available zoom level, triangles, and hulls. Nodes are the most permit an image of any size to be effi- fundamental element of a TIN and the ciently viewed in a geomashup. Viewing only element type that references spa- or adding any part of a tileset to a geo- tial coordinates (x,y,z). An edge is an viewer requires reading only a few small oriented line segment that connects two tiles from any available Internet source nodes. Three edges connect three nodes that is hosting it. to form a triangle that satisfies the tileset cache: Tiles are downloaded cached Delaunay criterion. Triangles represent locally when initially requested. The tile elementary areas of the surface that de- cache can be cleared using the Clear tile- scribe topological relationships between set cache button on the Storage tabbed all other elements of the TIN data. A panel of the General System Preferences hull represents the area covered by a TIN (Tools/System/Preferences) or from the structure. Interpolation of z-values is Options menu in the Display Manager. only valid within a hull region. tileset size: The time it takes to view or TIN object: A TIN, or Triangulated Irregu- refresh a view of a tileset is independent lar Network, object represents a continu- of its size. Any view always directly ac- ous surface as a set of conterminous tri- cesses and reads the few tiles that are re- angles computed from irregularly spaced quired at the view’s scale or zoom level. 3D points. TIN topology is more re- The tileset’s directory hierarchy means strictive than the topology of other co- that any individual tile can be directly ordinate data objects; every node is part located. The small tiles, made even of some polygon, every polygon is a tri- smaller by lossy compression, insure that angle, and every triangle satisfies the they can be rapidly read even when they Delaunay criterion. (See also: Delaunay are read over the Internet or a local net- criterion.) work or even from a DVD. A single tile- title bar: The area across the top of a win- set can contain a few thousand or 100s of dow that displays the name of the win- millions of tiles in a single directory struc- dow, the resize graphic, the iconifying ture. button, and the close button. tileset structure: A tileset can be flat, with TM: Thematic Mapper. A sensing device on all tile files in a single directory, or use a the Landsat satellite that scans and stores scale-pyramided hierarchical directory 7 individual images in spectral bands rang- structure of tile files. MicroImages’ tileset ing from the blue wavelengths up to those raster objects are also hierarchical tileset in the thermal infrared. structures. TNTatlas®: A free product in the TNT fam- tiling: Assembling large images from smaller ily for publication of spatial data that is segments that have common angular ori- graphically organized into stacks for entations, cell sizes, and map projections. point-and-click navigation through all in- The process is similar to that of assem- formation of interest. An atlas may also bling floor tiles, except that the raster be a single display or page layout with or tiles may overlap at the onset. (See also: without layer visibility controlled by map montage, mosaic.) scale. TIN Densification: A DEM extraction TNTbrowser™: A free, standalone Java method that builds a TIN surface from applet for use with TNTserver. This prod- the initial set of user-supplied tie points, uct was supplanted by TNTmap Builder and then iteratively densifies the TIN ob- and TNTmap Viewer. Now web tilesets ject. The process looks in the middle of produced in TNTmips and your browser

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are used for viewing your and others GIS (raster, vector, CAD, relational database, data over the web. and other layer types) from TNT Project TNTclient™: MicroImages’ free applet for Files and other popular geodata formats. web browsers that works with TNTserver. This product is no longer supported be- TNTclient can be requested in Java or cause technological advances have made HTML versions. This product was sup- it obsolete. planted by TNTmap Builder and TNT- TNTsim3D™: A free, standalone program for map Viewer. Now web tilesets produced Windows that lets you fly over 3D ter- in TNTmips and your browser are used rains with keybord or joystick controls. for viewing your and others GIS data over This product is no longer supported be- the web. cause you can now view your geospatial TNTedit™: Provides professional, interac- data created in TNTmips in 3D in Google tive tools to create, georeference, and Earth. edit project materials consisting of vec- TNTview®: Provides the visualization capa- tor, raster, CAD, TIN, and relational da- bilities of TNTmips and some interpre- tabase products. tive abilities for those who do not require TNTlite®: A free version of TNTmips for the full set of features included in TNT- small-scale projects. TNTlite is not a mips. demo, but a full-featured geospatial toggle button: A toggle button offers an on/ analysis software package (now called off control option for the current pro- TNTmips Free). cess. A toggle button’s label tells what TNTmap Builder: Lets you select and ar- state it controls, and it is preceded by a range map layers from any number of graphic indicator of the on/off state of WMS sources. Launches views of se- the button. lected layers in your choice of TNTmap toolbar: Row of icons appearing below the Viewer or other WMS viewers, such as menubar that provides direct access to Google Earth, Google Maps, or NASA’s tools and other actions. World Wind. ToolTip: A ToolTip pops in naming the menu TNTmap Viewer: Lets you view map layers item selection that duplicates the func- from any number of WMS sources. This tion of the icon button when the mouse viewer is launched from the layers se- cursor pauses over an icon button. lected in TNTmap Builder. topographic map or topo map: A map that TNTmips®: The latest, full-featured version uses colors and symbolic patterns to rep- of the Map and Image Processing Sys- resent the general surface features of the tem from MicroImages, Inc. earth, such as grassland, forest, marsh, TNTmips® Basic: A very low cost version of agricultural, urban, and barren rock. TNTmips for small-scale projects. topography: The features of the actual sur- TNTmips Basic is not a demo, but a full- face of the earth, considered collectively featured geospatial analysis software according to their form (for example, package with support for larger images grassland, cultivated, desert, forest, than allowed by TNTmips Free. swamp). A single feature, such as one TNTmips® Free: A free version of TNTmips mountain or one valley, is called a topo- for small-scale projects. TNTmips Free graphic feature. is not a demo, but a full-featured geospa- topology or vector topology: A description tial analysis software package. of the relationship between node, line, TNTsdk®: A software development kit for and polygon elements in a vector object. computers equipped with a full TNTmips Three levels of vector topology are avail- license to create custom products for dis- able for RVC vector objects: polygonal, tribution and use with the TNT prod- planar, and network. Polygonal topol- ucts. ogy is the highest, or strictest, level of topology. Polygonal topology requires TNTserver™: Lets you directly publish over that no two nodes have the same X and Y an intranet or the Internet your geodata

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coordinates, all lines start and end in transcoder: A device that converts video nodes, lines do not intersect without sepa- signal formats from an input type (like ration by nodes, enclosed areas are de- SVHS) to an output type (like RGB ana- fined as polygons, and any point can be in log). at most one polygon. Planar topology transfer rate: The number of XY coordi- requires that all lines start and end in nodes nate pairs produced per second when you and lines do not intersect without separa- are digitizing with the streaming method. tion by nodes, just as for polygonal objects. However, polygon information is Transformed Vegetation Index: A com- not maintained (which means planar ob- monly used vegetation index derived from jects have no polygons). Network topol- images of certain spectral bands. The ogy places nodes at the start and end of TVI is equal to the square root of the all lines, but lines may cross themselves quotient of the photo-infrared minus the or other lines and there are no polygons. red band, and the photo-infrared plus the All three topology types may be either red band {SQRT[(IR - red) / (IR + red)]}. 2D or 3D. Topology for polygonal and Common color-infrared image sources planar 3D objects is maintained in the X- that TNTmips uses to compute TVI in- Y plane, which means that polygon di- dex rasters include Landsat MSS and TM, mensions and the location of nodes sepa- SPOT CIR, 35mm CIR film, 9" CIR film, rating lines that would otherwise cross are and CIR video. determined by projecting onto the X-Y translation curve: The curve used to ad- plane. The constraint imposed by 2D just a raster object’s cell values to the topology on 3D objects is eliminated by brightness values used for display. TNT- network topology, which allows two nodes mips offers a selection of different trans- to have the same X and Y coordinates. lation curves (including linear) that are Polygonal topology is necessary for ob- normally selected to strengthen the vi- jects such as soil maps and property own- sual contrast in the display representa- ership maps. Planar topology may be tion. suitable for hydrology in the absence of transliterate: To represent the words of lakes or road systems that lack underpasses one language, with the alphabet of an- and overpasses or other features that re- other language. Usually the language is quire network topology for correct rep- foreign to the reader, and the alphabet is resentation. familiar. topology errors: Violations of the TNT- transparent color: The ability to overlay mips vector topology, such as line ele- one color image over another image or ments with polygonal or planar topology map so that the spatial details of both that are missing nodes at the point of are revealed for comparison is achieved intersection, or polygons with polygonal with transparent color. The colors that topology that overlap without defining result from such an overlay depend on an intersection polygon. TNTmips pro- whether the color in the images is addi- cesses that refer to the vector topology tive or subtractive. information either will not work, or will transparent patterns: Patterns that only return erroneous results if the input vec- partially obscure the image upon which tor object has topology errors. they are superimposed are transparent. trace: To create a vector line element by For example, a pattern could consist of a manually or interactively tracing over line drawing of a duck that leaves the remain- images in a raster object. der of the pattern tile transparent. When training set or prototype: A group of this pattern is used to fill a polygon that sample cells in an image known to repre- contains a lake, the lake colors and fea- sent a feature type or ground cover of tures will be visible through the transpar- interest defined by the user from his or ent portions of each tile. her knowledge of the site (perhaps trend: A steady change in contrast across an through ground visitation or detailed image. The change is introduced by the airphoto interpretation). collection device or by the geometric ori-

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entation of the instrument in relation to the Earth’s surface. TriDEF: An inexpensive application that converts Google Earth views into stereo — U — using DirectX (Windows only). tropic of Cancer: the parallel 23° 27' north underlay: To place a raster object so that it of the equator that marks the position at appears to be behind an existing object or which the sun is directly overhead at the image and will show around the perimeter summer solstice. This latitude is the and through any internal data holes in northernmost latitude reached by the the object on top. overhead sun. undershoot: A line that does not quite meet tropic of Capricorn: the parallel 23° 27' the line it was intended to intersect with south of the equator that marks the po- leaving a gap. sition at which the sun is directly over- Unicode: A character encoding scheme that head at the winter solstice, which is the is a super set of ASCII and Latin-1 with southernmost latitude reached by the room for 65,536 characters (a 16-bit or overhead sun. 2-byte set). The Unicode standard is still true scale: At large sizes, every map pro- in committee; it is in the care of the In- jection distorts the scale of distance, es- ternational Organization for Standardiza- pecially towards the edges. The location tion (ISO) and Unicode, Inc. (formerly of the true scale of a projection identi- the Unicode Consortium). Unicode itself fies the position where map measure- is a subset of ISO 10646, and in terms of ments correctly correspond to actual sur- ISO 10646, Unicode is the “Basic Multi- face distances. lingual Plane.” Unicode is designed to TSD: Tileset definition file extension. A tile- include all characters needed for the writ- set definition file defines the location ten languages of the modern world. and properties of a tileset. This defini- union: A merging of two vector objects such tion may be for a local tileset (both the that all the elements from two objects TSD and tileset files reside on an attached are copied to the resulting vector. storage device or a local network), a re- unsupervised classification or automatic mote linked tileset (TSD resides on a lo- interpretation: The operation of a group cal drive but the tileset is on the Inter- of multispectral image interpretation net), or an Internet tileset (TSD and tiles functions (such as K-means) that statisti- reside on the Internet). cally cluster cells into similar collections. TSR: (historical term) Terminate and Stay When the classification procedures are Resident. Under DOS, a software pro- complete, you identify and label the cess that became resident in memory ground features or conditions that the clus- when executed and performed some spe- ters represent. cial activity when the appropriate con- URL: Uniform Resource Locator. ditions were detected. For example, A USB: TSR program could be loaded to memory Universal Serial Bus. An external pe- and wait for a particular non-standard ripheral interface standard that uses series of keystrokes to initiate printing a biserial transmission created in January text screen out on paper. 1996. USDA: TVI: See: Transformed Vegetation Index. United States Department of Agri- culture. TYDAC: Formerly, a raster-based commercial GIS system. More recently, a pro- USDI: United States Department of the In- vider of ESRI and MapInfo software along terior. with consulting and related services. USF&WS: United States Fish and Wildlife Service of the USDI. USGS: United States Geological Survey.

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UTM: Universal Transverse Mercator map a point feature (such as a well); 2) lines, projection. which are curvilinear strings of coordinates that define a curved line (such as a stream); and 3) polygons, which are collections of lines that inscribe an area (such as a lake). A fourth type of element, — V — nodes, are necessary to maintain vector topology. variable: (in database queries) A named en- vector format: A data structure for repre- tity that has an assigned value. There are senting point and line data by means of four kinds of query variables: (1) those 2- or 3-dimensional geometric (Carte- are associated with the vector elements sian x,y or x,y,z) coordinates with topo- (like numlines, class, and startnode); (2) logical requirements (see the following those which are fields from a database definition for vector topology). In con- (perhaps Name, Acres, and Yield); (3) nection with GIS and computer graphics, those which control the drawing styles of “vector” can refer to a set of line seg- vector elements (like size, color, and ments joined end-to-end to make a fillcolor); and (4) the ten temporary user curved path in space. Vector objects also variables for numeric operations (temp0, have a set of attributes (such as ID num- temp1, temp2 ... temp9). For example, ber, color, drawing style) attached to the point element variable “size” can have them. a value from 1 to 64. It controls the size at which a point element is drawn. An vectorize: A general term for any technique assignment statement can change only that converts raster data into vector data. the values of drawing style and tempo- vector object: A collection of vector ele- rary variables; it cannot change the value ments and attributes stored in a complex of variables that are associated with a vec- topology as one entity in a TNTmips tor element or a database. project file. (See also: vector topology). variogram: A plot of the degree of spatial vector topology: A description of the rela- continuity based on the control points, tionship between node, line, and poly- that is points of known value in a vector gon elements in a vector object. Three or database object with continuous geo- levels of vector topology are available data. Variograms are used by the Kriging for RVC vector objects: polygonal, pla- method in the Surface Fitting operation nar, and network. Polygonal topology of Surface Modeling. is the highest, or strictest, level of to- vector: “A quantity possessing magnitude and pology. Polygonal topology requires that direction, represented by an arrow, the no two nodes have the same X and Y direction of which indicates the direction coordinates, all lines start and end in of the quantity and the length of which is nodes, lines do not intersect without sepa- proportional to the magnitude” (Random ration by nodes, enclosed areas are de- House). In connection with GIS and com- fined as polygons, and any point can be puter graphics, this term is used more in at most one polygon. Planar topol- loosely to refer to a set of vectors joined ogy requires that all lines start and end in end to end to make an arc or irregular line nodes and lines do not intersect without with a uniform set of properties. TNT- separation by nodes, just as for polygo- mips uses this looser definition and also nal objects. However, polygon informa- imposes topology and attaches a set of tion is not maintained (which means pla- attributes to the vector in place of the nar objects have no polygons). Network magnitude in the Random House defini- topology places nodes at the start and tion. end of all lines, but lines may cross themselves or other lines and there are no vector element: A vector object is made up polygons. All three topology types may of three basic types of elements that can be either 2D or 3D. Topology for po- have associated attributes 1) points, which lygonal and planar 3D objects is main- are single sets of coordinates that define

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tained in the X-Y plane, which means 1989. that polygon dimensions and the loca- VGA: Video Graphics Array. A microcom- tion of nodes separating lines that would puter video subsystem introduced by IBM otherwise cross are determined by pro- with the PS/2 microcomputer in 1987 with jecting onto the X-Y plane. The con- support for 256 simultaneous colors. The straint imposed by 2D topology on 3D VGA was an enhancement of the older objects is eliminated by network topol- EGA. (See also: CGA, EGA.) ogy, which allows two nodes to have the same X and Y coordinates. VHS: Video Home System. A popular format for low-cost video recording and Polygonal topology is necessary for ob- playback, common in home video sys- jects such as soil maps and property own- tems. ership maps. Planar topology may be suitable for hydrology in the absence of video capture: Some image display boards lakes or road systems that lack under- have the ability to display live broadcast passes and overpasses or other features or taped programming and then freeze that require network topology for cor- and grab an image, storing it in the rect representation. computer’s memory or on disk. vector units: The units in which vector video digitizing board: A video interface coordinates and vector object extent are circuit board installed in a PC that samples expressed. These units are specific to or frame-grabs a video frame and con- individual vector objects and are depen- structs a digital image. Video digitizing dent on how the vector was created. The boards can be used for non-standard, higher unit size may be a screen pixel and the resolution video sources. (See also: frame- object extents the same as the drawing grabbing.) area in pixels if the vector object was video field: The image you see on a standard drawn without a reference object. The TV screen is composed of a set of about unit size is related to the number of ras- 480 horizontal lines. The lines are pro- ter cells if the vector is created using an jected in two passes of the signal beam. ungeoreferenced raster for reference; the Each pass only projects every other line object extents equal the number of raster of the image: the odd lines in one pass, cells times the cell size. The units corre- and the even lines in the next pass. One spond to geographic coordinates and the scan takes 1/60 of a second, so the whole object extents correspond to the geo- picture (the frame) is refreshed every 1/ graphic extents if the vector is created 30th of a second. over a georeferenced object. A field contains every other line of the vegetation index: The output from stan- complete video image. The primary field dard manipulations of multispectral im- contains the odd lines; the secondary field age raster objects. The system processes contains the even lines. the input spectral information and cre- video frame: A complete video image, which ates output raster objects whose cell val- consists of two interlaced fields Odd lines ues represent the site’s biophysical prop- of the frame are contained in the pri- erties: amount of vegetation, leaf area, mary field which is alternated with the greenness, brightness, and wetness. secondary field which contains the even VersaCAD: A popular, commercial micro- lines. The primary field lasts 1/60 of a computer Computer Aided Design (CAD) second in standard broadcast video. The software package developed and mar- secondary field follows in the next 1/60 keted by Archway Systems, Inc. of a second. The entire frame takes 1/30 vertex: The point at which a line changes of a second to display. There is a differ- direction or terminates. ence of 1/60 of a second between alternate lines in the image. VESA: Video Electronics Standards Associa- tion. An international standards organi- view: The current contents of the view can- zation for computer graphics founded in vas. view canvas: The area of the View window

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used for layer display. as section, township, and range or create viewshed: The boundaries of sight from a a multiline DataTip from a number of single vantage point, assuming an unob- different fields, such as address, owner structed surface (disregard trees and build- name, and property value for a parcels ings). The TNTmips Viewshed process vector object. takes an elevation raster object, and com- virtual process: (for MIPS v3.3 and ear- putes the viewshed for selected points in lier) An operation performed on a raster the area. or vector object that is bigger than the view window: The TNTmips display pro- display screen (rasters up to 32,000 x cess always works with at least two win- 32,000 cells and vector collections of up dows: the control window and one or more to 2 billion coordinate pairs). You set up view windows. The control window pre- and guide the process on the display sents process options and controls, and screen, and the system applies the pro- the view window displays the images. cedure to the whole image. vignetting: Darkening at the edges and cor- VMap0: An improved version of the DCW, ners of an optical image. Vignetting oc- also distributed by NGA. VMap1 is a curs because lenses are physically unable higher resolution of VMap0 and is also to pass as much light to the fringe of an publicly available. VMap2 is classified. optical field as they do to its center. Sev- volume: An individual storage device such eral techniques compensate for vignett- as a tape or floppy disk. ing, but it is almost always present to some VPF: Vector Product Format is used by NGA degree. For color rasters, vignetting for the digital distribution of its map prod- means that the color of a feature at the ucts (DCW, VMap0...) edge or corner of an image may not match the color of that same feature in the cen- VQ Filtering: An image transformation ter. procedure in Hyperspectral Analysis. This procedure is related conceptually virtual display: A display management to the Self-Organizing Map (SOM) clas- scheme that displays as much of an image sifier. The VQ Filtering procedure ap- as will fit on the monitor, while buffering plies the SOM classifier to the image to the rest of the image in a temporary file derive 256 spectral classes and assigns from a RAM disk or the hard drive. The each image cell to the class with the closest user never needs to give new file infor- mean value in spectral space. The re- mation in order to access another por- sulting residual (filtered) image of each tion of the image. A virtual display works input band shows how well each cell fits like a window that can slide anywhere on its assigned class at that wavelength. a raster object. How quickly it moves depends on the hardware available. virtual field: A TNTmips database field that draws information from other database fields. This information can be used di- — W — rectly or combined with the information from other fields or additional compo- warping: Any process in which an object is nents. There are two types of virtual stretched differentially so as to change fields: numeric, which are referred to as its internal geometry. This shape change computed fields, or strings, which are could be defined by any one of many called string expression fields. An ex- transformations, such as changing a map ample of a computed field is population projection, trilateration to change the density, which may take population from absolute position of specified nodes in one table, area from another, make the the vector object, fitting a polynomial division and apply appropriate conver- to a surface, least squares movement of sion factors for the desired output units. control nodes, and so on. A string expression field might concat- watershed: The entire area drained by a enate the contents of separate fields, such stream and all of its tributaries, with all

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runoff draining to the same outlet. In web browser or other web application nature the outlet may be a lake, the ocean, (e.g., Google Maps, Google Earth, or or other water body. In the Watershed NASA World Wind). Such tilesets can process, the outlet may also be the point also be viewed in TNTmips Pro and where a particular flow path intersects TNTmips Basic. the boundary of the elevation raster be- wetness: The physical property mapped by ing analyzed. Synonym: catchment. Kauth’s greenness, brightness, wetness watershed basin: The area draining to any transformations on Landsat TM images. particular point in the landscape (called It measures how wet the combined veg- a seed point); a subwatershed or etation and soil surface is, including the subcatchment. Standard basins in the wa- water suspended in the vegetation bio- tershed process are generated using mass. stream junctions as seed points, so a stan- WFS: Web Feature Service. dard basin is the area drained by a par- widget: ticular tributary system of the main An interface component; that is, a stream. graphical X object such as a button, separator, menu bar, or scroll bar. Widgets watershed outlet: The lowest point in a are composed of data structures and pro- watershed toward which all water drains. cedures. Widget manipulations are sup- In nature the watershed outlet may be a ported by Xtoolkits; in particular by GUI lake, the ocean, or other water body. In libraries such as the one from OSF/Motif. the Watershed process, the outlet may window manager: also be the point where a particular flow A special client applica- path intersects the spatial boundary of tion in X that provides user controls for the elevation raster being analyzed. window size and position. Several window managers are available for X. TNT- watershed seed point: Any specified point mips under MI/X with X Desktop uses in the landscape used to determine the the TWM window manager. upslope area (basin) that drains to that wireframe: point. A graphical representation of a two-dimensional or three-dimensional waypoint: (also called a stop) an intermedi- solid or surface by means of regularly- ate point along a route that must be vis- spaced, connected line segments. The ited and is consequently included in your wireframe surface looks as if it had been network analysis. molded by a flexible wire mesh. Com- WCS: Web Coverage Service. puter systems use wireframe representa- website: A virtual location on the World tions for many intermediate 3D render- Wide Web consisting of a collection of ings because they take much less process- interlinked pages that collectively rep- ing time to create and manipulate than a resent a company, organization, or indi- continuous-surface representation. vidual. A website is located by its URL. WMMR-MED: Weighted majority with mini- Web Map Service: Produces views of geo- mum range-median. This is one of the referenced data dynamically from spa- raster enhancement filters. The WMMR- tial data. This specification standardizes MED filter is a nonlinear edge-enhance- the way in which clients request views ment filter that also suppresses image and servers describe their data holdings. noise (outlier values). Web Terrain Service: Produces views of WMS: Web Map Service. georeferenced data over the Internet. WORM drive: (historical term) Write Once, Can provide 3D perspective views in a Read Many drive. A type of drive that 2D pictorial format, such as PNG, GIF, reads and writes to non-erasable optical or JPEG. This specification standardizes disks, which are used for permanent, file the way in which clients request views storage. Data is recorded with reflective and servers describe their data holdings. pits in the coating laid on the surface of a web tileset: A tileset prepared for use with a glass or metal disk. Once the pits have been burned into the coating, they can-

page 73 Glossary for Geospatial Analysis

not be removed, which makes this me- library that contains higher-level mecha- dium non-erasable. (See also: erasable op- nisms than Xlib for generic tasks like tical cartridge, erasable optical drive, op- drawing window borders, scroll bars, and tical disk) buttons. W3C: World Wide Web Consortium. X Window System: A standard method of WTS: see Web Terrain Service. handling displays that can be used to build a windowing environment. Two popular GUI’s, Motif and OpenLook, have been built on the X standard. X-Y digitizing tablet: A peripheral device — X — for manually translating line and point data (like engineering and technical draw- X client: A program that uses the X server’s ings) into some computer format (usu- services, including applications programs, ally vector or CAD). The drawing is which may run either on the same ma- secured to the tablet, and the operator chine or elsewhere on the network. The positions the device’s cursor (which may GUI itself is a client. TNTmips is a cli- look like a pen or a computer mouse ent. NOTE: an X client is software, not with a crosshair lens) over lines and other hardware as the term “client” is used in elements, clicking a button or pressing a other networking contexts. key to record a coordinate. X display: A keyboard, mouse, and one or more screens. X font: A file in the X Window System that — Y — contains the bitmapped character descrip- tions for a particular font. yottabyte, Ybyte, or YB: A unit of mea- 80 Xlib: A C library of low-level X commands at surement for 2 (approximately) the heart of the X Window System. Xlib 1,000,000,000,000,000,000,000,000 commands do things like draw lines, open bytes, 1,000,000,000,000,000,000,000 and close windows, fill polygons, and track kilobytes, 1,000,000,000,000,000,000 the mouse and other user events. It is megabytes, 1,000,000,000,000,000 possible to write X applications com- gigabytes, 1,000,000,000,000 terabytes, pletely from Xlib commands (just as it is 1,000,000,000 petabytes, 1,000,000 possible to write complicated software in exabytes, or 1,000 zettabytes. (See also: Assembler), but it is easier to use higher- bit, byte, exabyte, gigabyte, kilobyte, level commands, such as those in various megabyte, petabyte, terabyte, Xtoolkits. zettabyte.) XML: Extensible Markup Language. XNP: X Network Protocol. A high-level protocol that defines data structures for communicating between clients and servers. — Z — X server: The X program that manages the zettabyte, Zbyte, or ZB: A unit of mea- display and runs locally on the terminal surement for 270 (approximately) or computer on the desktop. The server controls output to the display, handles 1,000,000,000,000,000,000,000 bytes, input, and manages the windows, draws 1,000,000,000,000,000,000 kilobytes, 1,000,000,000,000,000 megabytes, two-dimensional graphics as needed, and 1,000,000,000,000 gigabytes, sends messages. For Mac OS X machines, 1,000,000,000 terabytes, 1,000,000 the X server for TNTmips is provided by petabytes, or 1,000 exabytes. (See also: the system vendor. For Windows machines, MicroImages supplies its own X bit, byte, exabyte, gigabyte, kilobyte, server. megabyte, petabyte, terabyte, yottabyte.) Xtoolkit or Xt Intrinsics: Any subroutine

page 74 Glossary for Geospatial Analysis zoom level: A tileset can have one or many zoom levels. The maximum zoom level is the most detailed, or highest resolution, zoom level. The minimum zoom — 1, 2, 3 — level may be the full view of an image. A particular tileset may have a limited num- 16-bit raster object: A raster in which each ber of zoom levels when it is displayed in cell is represented by two bytes (16 bits) combination with other tilesets. The and can therefore assume 65,536 possible prerendered zoom levels for a tileset de- values. Elevation data commonly is ex- termine its zoom level range, pressed in 16-bit data. When color com- Zoom Transfer Scope or ZTS: An optical- posite images are stored in 16-bit rasters, mechanical device produced and marketed 5 bits represent the intensity level for by Bausch and Lomb. With it you can red, 5 bits green, and 5 bits blue (the 16th view and overlay two images through bit is typically unused). With this scheme separate optical paths. Usually one eye (32 possible levels for each color), each views a reference map and the other a cell in a 16-bit composite color raster portion of a color airphoto. The scale, can take any one of 32,768 possible col- position, and orientation of either opti- ors. cal path can be changed so that the 2D histogram: A two dimensional histo- airphoto matches the map in some local gram can be created from two single his- area. You then refer to the airphoto and tograms to give a visual sense of the simi- mark interpretation lines on the map or larity between the source raster objects. a transparent overlay. As the airphoto is moved slightly to register another sub- 24-bit raster object: A raster in which each section, you compile a map that has a cell is represented by three bytes (24 bits) minimum amount of distortion induced and can therefore assume 16,777,216 by the airphoto. possible values. When color images are stored in 24-bit rasters, 8 bits represent the intensity level for red, 8 bits green, and 8 bits blue. With this scheme (256 possible levels for each color), each cell in a 24-bit color raster can take any one of 16,777,216 possible colors. 3D surface modeling: Rendering a 3D surface from raster objects. Either a single object can be used to control both the height and the graytone in the display, or an elevation raster can be matched with a set of color image rasters for a real-world 3D image. (See also: solid modeling.) 3DMax™: Stereo shutter glasses for 3D viewing. 3D scene: A 2D projection of three dimensional features into a viewing plane located at an arbitrary position and angle in 3D space, in such a way as to preserve the visual appearance of a third spatial dimension. (Open GIS Consortium) 4-bit raster object: A raster in which each cell is represented by a nibble (half a bite) and can therefore have 16 possible values. The TNT products use 4-bit raster objects for class rasters having 16 or fewer classes and for dithered print-rasters. 5-5-5 composite color conversion method: page 75 16-bit color data uses 15 of the 16 bits to store the color intensity information: 5 bits to represent the intensity level for red, 5 bits for green, and 5 bits for blue GlossaryAdvanced for Geospatial AnalysisSoftware for Geospatial Analysis G L MicroImages, Inc. publishes a complete line of professional software for advanced O geospatial data visualization, analysis, and publishing. Contact us or visit our web S S site for detailed product information. A TNTmips Pro TNTmips Pro is a professional system for fully integrated GIS, image R analysis, CAD, TIN, desktop cartography, and geospatial database management. Y TNTmips Basic TNTmips Basic is a low-cost version of TNTmips for small projects. TNTmips Free TNTmips Free is a free version of TNTmips for students and profes- sionals with small projects. You can download TNTmips Free from MicroImages’ web site. TNTedit TNTedit provides interactive tools to create, georeference, and edit vector, image, CAD, TIN, and relational database project materials in a wide variety of formats. TNTview TNTview has the same powerful display features as TNTmips and is perfect for those who do not need the technical processing and preparation features of TNTmips. TNTatlas TNTatlas lets you publish and distribute your spatial project materials on CD or DVD at low cost. TNTatlas CDs/DVDs can be used on any popular computing platform. TNTserver TNTserver lets you publish TNTatlases on the Internet or on your intranet. Navigate through geodata atlases with your web browser and the Web Map Service compliant TNTmap JavaScript and dynamic HTML client. Index A...... 3 J ...... 37 B...... 7 K...... 38 C...... 10 L ...... 39 D...... 17 M ...... 41 E ...... 22 N ...... 45 F ...... 25 O...... 47 G...... 29 P ...... 48 H...... 32 Q...... 53 I ...... 34 R...... 53 S ...... 56 T ...... 63 ®¤ U...... 68 MicroImages,V...... Inc. 69 W...... 72 11th Floor – Sharp Tower 206 South 13thX...... Street 73 Lincoln, NebraskaY...... 68508-2010 USA 73 Z ...... 74 Voice: (402)477-9554 email: [email protected] FAX: (402)477-9559 page 761, 2, 3 ...... Internet: www.microimages.com 74