Analog Video Encoding Formats Ntsc
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ANALOG VIDEO ENCODING FORMATS NTSC NTSC is the analog television system in use in the United States and many other countries, including most of the Americas and some parts of East Asia. It is named for the National Television System(s) Committee, the industry-wide standardization body that created it. Analog television encodes picture information by varying the voltages and/or frequency of the signal. ... The Americas refers collectively to North and South America, as a relatively recent and less ambiguous alternative to the name America, which may refer to either the Americas (typically in languages other than English, where it is often considered a single continent) or to the United States (in English and...East Asia can be defined in either cultural or geographic terms. ... History The National Television Systems Committee was established in 1940 by the Federal Communications Commission (FCC) to resolve the conflicts which had arisen between companies over the introduction of a nationwide analog television system in the U.S. The committee in March 1941 issued a technical standard for black and white television. This built upon a 1936 recommendation made by the Radio Manufacturers Association (RMA) that used 441 lines. With the advancement of the vestigial sideband technique for broadcasting that increased available bandwidth, there was an opportunity to increase the image resolution. The NTSC compromised between RCA's desire to keep a 441-line standard (their NBC TV network was already using it) and Philco's desire to increase it to between 600 and 800, settling on a 525-line transmission. 1940 was a leap year starting on Monday (link will take you to calendar). ... The Federal Communications Commission (FCC) is an independent United States government agency, created, directed, and empowered by Congressional statute. ...1941 was a common year starting on Wednesday (link will take you to calendar). ...This article is about the term as used in media and computing; for more specific uses, see Black and White. ...1936 was a leap year starting on Wednesday (link will take you to calendar). ...Single-sideband modulation (SSB) is a refinement of the technique of amplitude modulation designed to be more efficient in its use of electrical power and bandwidth. ...Analog Bandwidth is the width, usually measured in hertz, of a frequency band f2 - f1. ...RCA, formerly an initialism for the Radio Corporation of America, is now a trademark used by two companies for products descended from that common ancestor: Thomson Consumer Electronics, which manufactures RCA-branded televisions, DVD players, video cassette recorders, direct broadcast satellite decoders, camcorders, audio equipment, telephones, and related accessories; and...The 1986 Peacock logo, designed by Chermayeff & Geismar. ... In January 1950 the Committee was reconstituted, this time to decide about color television. In March 1953 it unanimously approved what is now called simply the NTSC color television standard. The updated standard retained full backwards compatibility with older black and white television sets. 1950 was a common year starting on Sunday (link will take you to calendar). ... 1953 is a common year starting on Thursday. ... The FCC had briefly approved a different color television system starting in 1950. It was developed by CBS and was incompatible with black and white broadcasts. That system used a rotating color wheel, reduced the number of scanlines from 525 to 405, and increased the field rate from 60 to 144 (but had an effective frame rate of 24 frames per second). Delay tactics by rival RCA kept the system off the air until mid-1951, and regular broadcasts only lasted a few months before manufacture of CBS-compatible systems was banned by the National Production Authority (NPA). Most of the existing devices were soon destroyed and only two receivers are known to exist today. The CBS system was rescinded by the FCC in 1953 and was replaced later that year by the NTSC color standard, which had been developed with the cooperation of several companies including RCA and Philco. A variant of the CBS system was later used by NASA to broadcast pictures of astronauts from space. CBSs first color logo, which debuted in the fall of 1965. ... In the arts of painting, and photography, color theory is a set of basic rules for mixing color to achieve a desired result. ...A scanline is a line on a CRT tube, made up of dots. ...Frame rate, or frame frequency, is the measurement of how quickly an imaging device can produce several consecutive images, called frames. A third "line sequential" system from Color Television, Incorporated (CTI) was also considered. The CBS and final NTSC systems were called "field sequential" and "dot sequential" systems, respectively. The first commercially available color NTSC television camera was the RCA TK- 40A, introduced in March 1954. It was replaced later that year by an improved version, the TK-41, which became the standard camera used through much of the 1960s. A professional video camera (often called a television camera even though the use has spread) is a high-end device for recording electronic moving images (as opposed to a movie camera, that records the images on film). ... The RCA TK-40 is considered to be the first color television camera, initially used for special broadcasts in late 1953, and with the follow-on TK-40A actually becoming the first to be produced in quantity in March 1954. ...1954 was a common year starting on Friday of the Gregorian calendar. ...Events and trends The 1960s was a turbulent decade of change around the world. ... The NTSC standard has since been adopted by many other countries, for example most of the Americas and Japan. The Americas (sometimes referred to as America) is the area including the land mass located between the Pacific Ocean and the Atlantic Ocean, generally divided into North America and South America. ... Technical details The NTSC format—or more correctly the M format; see broadcast television systems—consists of 29.97 interlaced frames of video per second. Each frame consists of 480 lines out of a total of 525 (the rest are used for sync, vertical retrace, and other data such as captioning). The NTSC system interlaces its scanlines, drawing odd-numbered scanlines in odd-numbered fields and even- numbered scanlines in even-numbered fields, yielding a nearly flicker-free image at its approximately 59.94 hertz (nominally 60 Hz / 1.001) refresh frequency. This compares favorably to the 50 Hz refresh rate of the 625-line PAL and SECAM video formats used in Europe, where 50 Hz alternating current is the standard; flicker is more likely to be noticed when using these standards. Interlacing the picture does complicate editing video, but this is true of all interlaced video formats, including PAL and SECAM. There are several broadcast television systems in use in the world today. ... Interlacing is a method of displaying images on a raster-scanned display device, such as a cathode ray tube (CRT). ...Video is the technology of processing electronic signals representing moving pictures. ...This article is about the unit of time. ...The flicker fusion threshold (or flicker fusion rate) is a concept in the psychophysics of vision. ...The hertz (symbol Hz) is the SI unit of frequency. ...Sine waves of various frequencies; the lower waves have higher frequencies than those above. ...The refresh rate (or vertical refresh rate, vertical scan rate) is the maximum number of frames that can be displayed on a monitor in a second, expressed in Hertz. ...For other meanings of PAL see PAL (disambiguation). ...SÉCAM (Séquentiel couleur à mémoire, French for sequential colour with memory) is an analog color television system first used in France. ...World map showing location of Europe A satellite composite image of Europe Europe is geologically and geographically a peninsula, forming the westernmost part of Eurasia. ...An alternating current (AC) is an electrical current where the magnitude and direction of the current varies cyclically, as opposed to direct current, where the direction of the current stays constant. ... The NTSC refresh frequency was originally exactly 60 Hz in the black and white system, chosen because it matched the nominal 60 Hz frequency of alternating current power used in the United States. It was preferable to match the screen refresh rate to the power source to avoid wave interference that would produce rolling bars on the screen. Synchronization of the refresh rate to the power cycle also helped kinescope cameras record early live television broadcasts, as it was very simple to synchronize a film camera to capture one frame of video on each film cell by using the alternating current frequency as a shutter trigger. In the color system the refresh frequency was shifted slightly downward to 59.94 Hz. Synchronization is coordination with respect to time. ... The term kinescope originally referred to a type of early television picture tube. ...Film refers to the celluloid media on which movies are printed Film is a term that encompasses motion pictures as individual projects, as well as the field in general. ... The mismatch in frame rate between NTSC and the other two video formats, PAL and SECAM, is the most difficult part of video format conversion. Because the NTSC frame rate is higher, it is necessary for video conversion equipment converting to NTSC to interpolate the contents of adjacent frames in order to produce new intermediate frames; this introduces artifacts, and a trained eye can quickly spot video that has been converted between formats. (See also stutter frame.) Frame rate, or frame frequency, is the measurement of how quickly an imaging device can produce several consecutive images, called frames. ... A video format describes how one device sends a video pictures to another device, such as the way that a DVD player sends pictures to a television, or a computer to a monitor.