PRECISE COLOR COMMUNICATION COLOR CONTROL from PERCEPTION to INSTRUMENTATION Knowing Color
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Colors and Fillstyle
GraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphicsGraphics andandandandandandandandandandandandandandandandandandandandandandandandandandandandandand TTTTTTTTTTTTTTTTTTETETETETETXETXETXETXETXETXETXETXEXEXEXEXEXEXEXEXEXEXEXEXEXEXEXEXEXEXXXXX Ordinary colors More colors Colorful Fill—in style Custom colors From one color to another Tricks Online L Part II – Graphics AT EX Tutorial PSTricks c 2002, 2003, The Indian T This document is generated by hyperref, pstricks, pdftricks and pdfscreen packages on an intel and is released under EX Users Group The Indian T pc pdf running Floor lppl T Trivandrum 695014, EX with iii, sjp http://www.tug.org.in gnu/linux Buildings,EX Users Cotton HillsGroup india 1/19 Ordinary colors More colors Fill—in style Custom colors From one color to another 2. Colorful Tricks Seeing the (ps)tricks so far, at least some of you may be wishing for a bit of color in the graphics. Here’s good news for such people: you can have your wish! PSTricks comes with a set of macros that provide a basic set of colors Online LAT X Tutorial and lets you define your own colors. However, it has some incompatibility with E the LATEX package color. However, David Carlisle has written a package pstcol Part II – Graphics which modifies the PSTricks color interface to work with LATEX colors. All of our examples in this chapter assumes that this package is loaded, using the PSTricks command \usepackage{pstcol} in the preamble. Note that this loads the pstricks package also, so that it need not be separately loaded. c 2002, 2003, The Indian TEX Users Group This document is generated by pdfTEX with hyperref, pstricks, pdftricks and pdfscreen packages on an intel pc running gnu/linux and is released under lppl The Indian TEX Users Group Floor iii, sjp Buildings, Cotton Hills Trivandrum 695014, india http://www.tug.org.in 2/19 Colorful Tricks 2.1. -
Color Theory for Painting Video: Color Perception
Color Theory For Painting Video: Color Perception • http://www.ted.com/talks/lang/eng/beau_lotto_optical_illusions_show_how_we_see.html • Experiment • http://www.youtube.com/watch?v=y8U0YPHxiFQ Intro to color theory • http://www.youtube.com/watch?v=059-0wrJpAU&feature=relmfu Color Theory Principles • The Color Wheel • Color context • Color Schemes • Color Applications and Effects The Color Wheel The Color Wheel • A circular diagram displaying the spectrum of visible colors. The Color Wheel: Primary Colors • Primary Colors: Red, yellow and blue • In traditional color theory, primary colors can not be mixed or formed by any combination of other colors. • All other colors are derived from these 3 hues. The Color Wheel: Secondary Colors • Secondary Colors: Green, orange and purple • These are the colors formed by mixing the primary colors. The Color Wheel: Tertiary Colors • Tertiary Colors: Yellow- orange, red-orange, red-purple, blue-purple, blue-green & yellow-green • • These are the colors formed by mixing a primary and a secondary color. • Often have a two-word name, such as blue-green, red-violet, and yellow-orange. Color Context • How color behaves in relation to other colors and shapes is a complex area of color theory. Compare the contrast effects of different color backgrounds for the same red square. Color Context • Does your impression od the center square change based on the surround? Color Context Additive colors • Additive: Mixing colored Light Subtractive Colors • Subtractive Colors: Mixing colored pigments Color Schemes Color Schemes • Formulas for creating visual unity [often called color harmony] using colors on the color wheel Basic Schemes • Analogous • Complementary • Triadic • Split complement Analogous Color formula used to create color harmony through the selection of three related colors which are next to one another on the color wheel. -
Understanding Color and Gamut Poster
Understanding Colors and Gamut www.tektronix.com/video Contact Tektronix: ASEAN / Australasia (65) 6356 3900 Austria* 00800 2255 4835 Understanding High Balkans, Israel, South Africa and other ISE Countries +41 52 675 3777 Definition Video Poster Belgium* 00800 2255 4835 Brazil +55 (11) 3759 7627 This poster provides graphical Canada 1 (800) 833-9200 reference to understanding Central East Europe and the Baltics +41 52 675 3777 high definition video. Central Europe & Greece +41 52 675 3777 Denmark +45 80 88 1401 Finland +41 52 675 3777 France* 00800 2255 4835 To order your free copy of this poster, please visit: Germany* 00800 2255 4835 www.tek.com/poster/understanding-hd-and-3g-sdi-video-poster Hong Kong 400-820-5835 India 000-800-650-1835 Italy* 00800 2255 4835 Japan 81 (3) 6714-3010 Luxembourg +41 52 675 3777 MPEG-2 Transport Stream Advanced Television Systems Committee (ATSC) Mexico, Central/South America & Caribbean 52 (55) 56 04 50 90 ISO/IEC 13818-1 International Standard Program and System Information Protocol (PSIP) for Terrestrial Broadcast and cable (Doc. A//65B and A/69) System Time Table (STT) Rating Region Table (RRT) Direct Channel Change Table (DCCT) ISO/IEC 13818-2 Video Levels and Profiles MPEG Poster ISO/IEC 13818-1 Transport Packet PES PACKET SYNTAX DIAGRAM 24 bits 8 bits 16 bits Syntax Bits Format Syntax Bits Format Syntax Bits Format 4:2:0 4:2:2 4:2:0, 4:2:2 1920x1152 1920x1088 1920x1152 Packet PES Optional system_time_table_section(){ rating_region_table_section(){ directed_channel_change_table_section(){ High Syntax -
Color Models
Color Models Jian Huang CS456 Main Color Spaces • CIE XYZ, xyY • RGB, CMYK • HSV (Munsell, HSL, IHS) • Lab, UVW, YUV, YCrCb, Luv, Differences in Color Spaces • What is the use? For display, editing, computation, compression, …? • Several key (very often conflicting) features may be sought after: – Additive (RGB) or subtractive (CMYK) – Separation of luminance and chromaticity – Equal distance between colors are equally perceivable CIE Standard • CIE: International Commission on Illumination (Comission Internationale de l’Eclairage). • Human perception based standard (1931), established with color matching experiment • Standard observer: a composite of a group of 15 to 20 people CIE Experiment CIE Experiment Result • Three pure light source: R = 700 nm, G = 546 nm, B = 436 nm. CIE Color Space • 3 hypothetical light sources, X, Y, and Z, which yield positive matching curves • Y: roughly corresponds to luminous efficiency characteristic of human eye CIE Color Space CIE xyY Space • Irregular 3D volume shape is difficult to understand • Chromaticity diagram (the same color of the varying intensity, Y, should all end up at the same point) Color Gamut • The range of color representation of a display device RGB (monitors) • The de facto standard The RGB Cube • RGB color space is perceptually non-linear • RGB space is a subset of the colors human can perceive • Con: what is ‘bloody red’ in RGB? CMY(K): printing • Cyan, Magenta, Yellow (Black) – CMY(K) • A subtractive color model dye color absorbs reflects cyan red blue and green magenta green blue and red yellow blue red and green black all none RGB and CMY • Converting between RGB and CMY RGB and CMY HSV • This color model is based on polar coordinates, not Cartesian coordinates. -
Estimation and Correction of the Distortion in Forensic Image Due to Rotation of the Photo Camera
Master Thesis Electrical Engineering February 2018 Master Thesis Electrical Engineering with emphasis on Signal Processing February 2018 Estimation and Correction of the Distortion in Forensic Image due to Rotation of the Photo Camera Sathwika Bavikadi Venkata Bharath Botta Department of Applied Signal Processing Blekinge Institute of Technology SE–371 79 Karlskrona, Sweden This thesis is submitted to the Department of Applied Signal Processing at Blekinge Institute of Technology in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering with Emphasis on Signal Processing. Contact Information: Author(s): Sathwika Bavikadi E-mail: [email protected] Venkata Bharath Botta E-mail: [email protected] Supervisor: Irina Gertsovich University Examiner: Dr. Sven Johansson Department of Applied Signal Processing Internet : www.bth.se Blekinge Institute of Technology Phone : +46 455 38 50 00 SE–371 79 Karlskrona, Sweden Fax : +46 455 38 50 57 Abstract Images, unlike text, represent an effective and natural communica- tion media for humans, due to their immediacy and the easy way to understand the image content. Shape recognition and pattern recog- nition are one of the most important tasks in the image processing. Crime scene photographs should always be in focus and there should be always be a ruler be present, this will allow the investigators the ability to resize the image to accurately reconstruct the scene. There- fore, the camera must be on a grounded platform such as tripod. Due to the rotation of the camera around the camera center there exist the distortion in the image which must be minimized. -
Cielab Color Space
Gernot Hoffmann CIELab Color Space Contents . Introduction 2 2. Formulas 4 3. Primaries and Matrices 0 4. Gamut Restrictions and Tests 5. Inverse Gamma Correction 2 6. CIE L*=50 3 7. NTSC L*=50 4 8. sRGB L*=/0/.../90/99 5 9. AdobeRGB L*=0/.../90 26 0. ProPhotoRGB L*=0/.../90 35 . 3D Views 44 2. Linear and Standard Nonlinear CIELab 47 3. Human Gamut in CIELab 48 4. Low Chromaticity 49 5. sRGB L*=50 with RGB Numbers 50 6. PostScript Kernels 5 7. Mapping CIELab to xyY 56 8. Number of Different Colors 59 9. HLS-Hue for sRGB in CIELab 60 20. References 62 1.1 Introduction CIE XYZ is an absolute color space (not device dependent). Each visible color has non-negative coordinates X,Y,Z. CIE xyY, the horseshoe diagram as shown below, is a perspective projection of XYZ coordinates onto a plane xy. The luminance is missing. CIELab is a nonlinear transformation of XYZ into coordinates L*,a*,b*. The gamut for any RGB color system is a triangle in the CIE xyY chromaticity diagram, here shown for the CIE primaries, the NTSC primaries, the Rec.709 primaries (which are also valid for sRGB and therefore for many PC monitors) and the non-physical working space ProPhotoRGB. The white points are individually defined for the color spaces. The CIELab color space was intended for equal perceptual differences for equal chan- ges in the coordinates L*,a* and b*. Color differences deltaE are defined as Euclidian distances in CIELab. This document shows color charts in CIELab for several RGB color spaces. -
Color Difference Delta E - a Survey
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/236023905 Color difference Delta E - A survey Article in Machine Graphics and Vision · April 2011 CITATIONS READS 12 8,785 2 authors: Wojciech Mokrzycki Maciej Tatol Cardinal Stefan Wyszynski University in Warsaw University of Warmia and Mazury in Olsztyn 157 PUBLICATIONS 177 CITATIONS 5 PUBLICATIONS 27 CITATIONS SEE PROFILE SEE PROFILE All content following this page was uploaded by Wojciech Mokrzycki on 08 August 2017. The user has requested enhancement of the downloaded file. Colour difference ∆E - A survey Mokrzycki W.S., Tatol M. {mokrzycki,mtatol}@matman.uwm.edu.pl Faculty of Mathematics and Informatics University of Warmia and Mazury, Sloneczna 54, Olsztyn, Poland Preprint submitted to Machine Graphic & Vision, 08:10:2012 1 Contents 1. Introduction 4 2. The concept of color difference and its tolerance 4 2.1. Determinants of color perception . 4 2.2. Difference in color and tolerance for color of product . 5 3. An early period in ∆E formalization 6 3.1. JND units and the ∆EDN formula . 6 3.2. Judd NBS units, Judd ∆EJ and Judd-Hunter ∆ENBS formulas . 6 3.3. Adams chromatic valence color space and the ∆EA formula . 6 3.4. MacAdam ellipses and the ∆EFMCII formula . 8 4. The ANLab model and ∆E formulas 10 4.1. The ANLab model . 10 4.2. The ∆EAN formula . 10 4.3. McLaren ∆EMcL and McDonald ∆EJPC79 formulas . 10 4.4. The Hunter color system and the ∆EH formula . 11 5. ∆E formulas in uniform color spaces 11 5.1. -
WHITE LIGHT and COLORED LIGHT Grades K–5
WHITE LIGHT AND COLORED LIGHT grades K–5 Objective This activity offers two simple ways to demonstrate that white light is made of different colors of light mixed together. The first uses special glasses to reveal the colors that make up white light. The second involves spinning a colorful top to blend different colors into white. Together, these activities can be thought of as taking white light apart and putting it back together again. Introduction The Sun, the stars, and a light bulb are all sources of “white” light. But what is white light? What we see as white light is actually a combination of all visible colors of light mixed together. Astronomers spread starlight into a rainbow or spectrum to study the specific colors of light it contains. The colors hidden in white starlight can reveal what the star is made of and how hot it is. The tool astronomers use to spread light into a spectrum is called a spectroscope. But many things, such as glass prisms and water droplets, can also separate white light into a rainbow of colors. After it rains, there are often lots of water droplets in the air. White sunlight passing through these droplets is spread apart into its component colors, creating a rainbow. In this activity, you will view the rainbow of colors contained in white light by using a pair of “Rainbow Glasses” that separate white light into a spectrum. ! SAFETY NOTE These glasses do NOT protect your eyes from the Sun. NEVER LOOK AT THE SUN! Background Reading for Educators Light: Its Secrets Revealed, available at http://www.amnh.org/education/resources/rfl/pdf/du_x01_light.pdf Developed with the generous support of The Charles Hayden Foundation WHITE LIGHT AND COLORED LIGHT Materials Rainbow Glasses Possible white light sources: (paper glasses containing a Incandescent light bulb diffraction grating). -
Accurately Reproducing Pantone Colors on Digital Presses
Accurately Reproducing Pantone Colors on Digital Presses By Anne Howard Graphic Communication Department College of Liberal Arts California Polytechnic State University June 2012 Abstract Anne Howard Graphic Communication Department, June 2012 Advisor: Dr. Xiaoying Rong The purpose of this study was to find out how accurately digital presses reproduce Pantone spot colors. The Pantone Matching System is a printing industry standard for spot colors. Because digital printing is becoming more popular, this study was intended to help designers decide on whether they should print Pantone colors on digital presses and expect to see similar colors on paper as they do on a computer monitor. This study investigated how a Xerox DocuColor 2060, Ricoh Pro C900s, and a Konica Minolta bizhub Press C8000 with default settings could print 45 Pantone colors from the Uncoated Solid color book with only the use of cyan, magenta, yellow and black toner. After creating a profile with a GRACoL target sheet, the 45 colors were printed again, measured and compared to the original Pantone Swatch book. Results from this study showed that the profile helped correct the DocuColor color output, however, the Konica Minolta and Ricoh color outputs generally produced the same as they did without the profile. The Konica Minolta and Ricoh have much newer versions of the EFI Fiery RIPs than the DocuColor so they are more likely to interpret Pantone colors the same way as when a profile is used. If printers are using newer presses, they should expect to see consistent color output of Pantone colors with or without profiles when using default settings. -
Creating 4K/UHD Content Poster
Creating 4K/UHD Content Colorimetry Image Format / SMPTE Standards Figure A2. Using a Table B1: SMPTE Standards The television color specification is based on standards defined by the CIE (Commission 100% color bar signal Square Division separates the image into quad links for distribution. to show conversion Internationale de L’Éclairage) in 1931. The CIE specified an idealized set of primary XYZ SMPTE Standards of RGB levels from UHDTV 1: 3840x2160 (4x1920x1080) tristimulus values. This set is a group of all-positive values converted from R’G’B’ where 700 mv (100%) to ST 125 SDTV Component Video Signal Coding for 4:4:4 and 4:2:2 for 13.5 MHz and 18 MHz Systems 0mv (0%) for each ST 240 Television – 1125-Line High-Definition Production Systems – Signal Parameters Y is proportional to the luminance of the additive mix. This specification is used as the color component with a color bar split ST 259 Television – SDTV Digital Signal/Data – Serial Digital Interface basis for color within 4K/UHDTV1 that supports both ITU-R BT.709 and BT2020. 2020 field BT.2020 and ST 272 Television – Formatting AES/EBU Audio and Auxiliary Data into Digital Video Ancillary Data Space BT.709 test signal. ST 274 Television – 1920 x 1080 Image Sample Structure, Digital Representation and Digital Timing Reference Sequences for The WFM8300 was Table A1: Illuminant (Ill.) Value Multiple Picture Rates 709 configured for Source X / Y BT.709 colorimetry ST 296 1280 x 720 Progressive Image 4:2:2 and 4:4:4 Sample Structure – Analog & Digital Representation & Analog Interface as shown in the video ST 299-0/1/2 24-Bit Digital Audio Format for SMPTE Bit-Serial Interfaces at 1.5 Gb/s and 3 Gb/s – Document Suite Illuminant A: Tungsten Filament Lamp, 2854°K x = 0.4476 y = 0.4075 session display. -
Color Space Conversion
L Technical Color Space Information Conversion The role of color space conversion in the process of scanning and reproduc- ing a color image begins the moment an image is captured by a scanner and continues through the point at which it is output on film. For the purpose of this article we will discuss conversions between three types of color systems: RGB, CIE, and CMYK. The RGB (Red, Green, & Blue) and CMYK (Cyan, Magenta, Yellow, & Black) color models have been described in greater detail in the Linotype-Hell Technical information piece entitled Color in Printing. For some background information on the CIE (Commission Internationale de l’Eclairage), please refer to Color Spaces and PostScript Level 2. CIE as a reference color space Most scanners acquire color in the form of RGB data. The majority of non- photographic printing methods employ CMYK inks or toners. In a closed sys- tem, where the characteristics of both the scanner and the printing method are well-defined, conversions may be made from RGB to CMYK through tables that maintain a reasonable level of color consistency. The process becomes somewhat more difficult as you add monitors, other scanners, proofing devices or printing processes that have different characteristics. It becomes critical to have a consistent yardstick, if you will, a means of con- verting between different color systems (and back again) without a loss in color fidelity. This is what CIE provides. Let’s start with some background on CIE, and then we will look at how it can be applied in an open system. Measuring color Light reflected off of, or transmitted through a colored object can be mea- sured by the wavelengths of light that are reflected or transmitted. -
Review of Measures for Light-Source Color Rendition and Considerations for a Two-Measure System for Characterizing Color Rendition
Review of measures for light-source color rendition and considerations for a two-measure system for characterizing color rendition Kevin W. Houser,1,* Minchen Wei,1 Aurélien David,2 Michael R. Krames,2 and Xiangyou Sharon Shen3 1Department of Architectural Engineering, The Pennsylvania State University, University Park, PA, 16802, USA 2Soraa, Inc., Fremont, CA 94555, USA 3Inno-Solution Research LLC, 913 Ringneck Road, State College, PA 16801, USA *[email protected] Abstract: Twenty-two measures of color rendition have been reviewed and summarized. Each measure was computed for 401 illuminants comprising incandescent, light-emitting diode (LED) -phosphor, LED-mixed, fluorescent, high-intensity discharge (HID), and theoretical illuminants. A multidimensional scaling analysis (Matrix Stress = 0.0731, R2 = 0.976) illustrates that the 22 measures cluster into three neighborhoods in a two- dimensional space, where the dimensions relate to color discrimination and color preference. When just two measures are used to characterize overall color rendition, the most information can be conveyed if one is a reference- based measure that is consistent with the concept of color fidelity or quality (e.g., Qa) and the other is a measure of relative gamut (e.g., Qg). ©2013 Optical Society of America OCIS codes: (330.1690) Color; (330.1715) Color, rendering and metamerism; (230.3670) Light-emitting diodes. References and links 1. CIE, “Methods of measuring and specifying colour rendering properties of light sources,” in CIE 13 (CIE, Vienna, Austria, 1965). 2. W. Walter, “How meaningful is the CIE color rendering index?” Light Design Appl. 11(2), 13–15 (1981). 3. T. Seim, “In search of an improved method for assessing the colour rendering properties of light sources,” Lighting Res.