"The Pb and Pr are the signals that form the three primary colors, 'b' being blue, and 'r'; being red. The two signals are combined mathematically in various ways to form the green component. "

Not quite.
Y, Pb, Pr can also be written as Y, R-Y, B-Y. In other words, Y, the luma signal is a combination of R, G & B.
R-Y (Pr) is the red signal - the RGB (Y) signal resulting in a Green/Blue (cyan) signal. B-Y is Blue - RGB resulting in an RG signal (yellow). Using simple algebra, the RGB components, (which made up the original signal) can be retreived.
ie:
(R-Y) + Y = red, (B-Y) + Y = Blue, Y - R - B = Green

All video signals originate as RGB, weather the source is a video camera or a computer. Y, Pr, Pb is a form of analogue compression.

This message was edited by automan on 12/31/01 14:35.33.