The TEA1002 is a

PAL Phase Alternating Line (PAL) is a color encoding system for analog television. It was one of three major analogue colour television standards, the others being NTSC and SECAM. In most countries it was broadcast at 625 lines, 50 fields (25 ...

video encoder chip produced by

Mullard Mullard Limited was a British manufacturer of electronics, electronic components. The Mullard Radio Valve Co. Ltd. of Southfields, London, was founded in 1920 by Captain Stanley R. Mullard, who had previously designed thermionic valves (US ...

in 1982 and used on the

Mattel Aquarius The Aquarius is a home computer designed by ''Radofin'' and released by ''Mattel Electronics'' in 1983. Based on the Zilog Z80 microprocessor, the system has a rubber chiclet keyboard, 4 kB of RAM, and a subset of Microsoft BASIC in ROM. It conn ...

computer, the AlphaTantel

Prestel Prestel was the Brand#Brand names and trademark, brand name of a videotex service launched in the UK in 1979 by BT Group#Post Office Telecommunications, Post Office Telecommunications, a division of the British Post Office Limited#History, Po ...

adapter and the ''Microvector 256'' color graphics display interface for

Nascom The Nascom 1 and 2 were single-board computer kits issued in the United Kingdom in 1977 and 1979, respectively, based on the Zilog Z80 and including a keyboard and video interface, a serial port that could be used to store data on a tape casset ...

and Gemini computers. It was also used on

teletext Teletext, or broadcast teletext, is a standard for displaying text and rudimentary graphics on suitably equipped television sets. Teletext sends data in the broadcast signal, hidden in the invisible vertical blanking interval area at the to ...

decoders and color bar generators associated with video test equipment. It generates 16 colors based on

Luminance Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through, is emitted from, or is reflected from a particular area, and falls wit ...

Chrominance Chrominance (''chroma'' or ''C'' for short) is the signal used in video systems to convey the color information of the picture (see YUV color model), separately from the accompanying Luma (video), luma signal (or Y' for short). Chrominance is usu ...

and

Saturation Saturation, saturated, unsaturation or unsaturated may refer to: Chemistry *Saturated and unsaturated compounds, a classification of compounds related to their ability to resist addition reactions ** Degree of unsaturation **Saturated fat or satu ...

, usually with the 8 basic colors being similar to the EBU 75% color bars.

Levels

According to the TEA1002 datasheet, colors are formed by the combination of three signals, roughly equivalent to the HSL colorspace: * ''

'' * ''Chroma'' ''phase'' (º, equivalent to ''hue angle'') * ''Chroma amplitude (%,'' equivalent to ''saturation'') Internally colors are stored in a 4-bit RGBI arrangement. There are three bits for the RGB components (generating 8 primary colors at full saturation but 75% luminance - similar to the EBU colour bars) and an ''inverter logic input'' bit that controls a variation of the base color (a 75% ''Luminance'' decrease for white; a 50% ''Chroma'' saturation decrease for all colors). The following table lists the internal signals and shows an approximation of the generated colors, as seen on a web standard sRGB monitor. Colors could be different when seen on an analog

CRT CRT or Crt most commonly refers to: * Cathode-ray tube, a display * Critical race theory, an academic framework of analysis CRT may also refer to: Law * Charitable remainder trust, United States * Civil Resolution Tribunal, Canada * Columbia ...

television Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, ...

. An alternate configuration of the chip allows it to output 95% luminance color bars - similar to BBC colour bars, more suited for usage in

decoders.

References

{{reflist Graphics chips

Levels

See also

References