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Teletext A television information retrieval service developed in the
United Kingdom in the early 1970s. It offers a range of
text-based information, typically including national,
international and sporting news, weather and TV
schedules. Subtitle (or closed captioning) information is
also transmitted in the teletext signal, typically on page
888 or 777.
YPbPr A color space used in video electronics, in particular in
reference to component video cables. YPbPr is the analog
version of the YCBCR color space; the two are
numerically equivalent, but YPBPR is designed for use in
analog systems whereas YCBCR is intended for digital
video. YPbPr is commonly called "component video", but
this is a misnomer, as there are many other types of
component video (mostly RGB with sync either on green
or one or two separate signals).
YPbPr is converted from the RGB video signal, which is
split into three components, Y, PB, and PR.
* Y carries luma (brightness) and sync information.
* PB carries the difference between blue and luma (B - Y).
* PR carries the difference between red and luma (R - Y).
Sending a green signal would be redundant, as it can be
derived using the blue, red and luma information.
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