The YUV color model is a color model used in the PAL television standard and in image compression. It uses the high bandwidthluminance signal (Y) and the two signals "U" and "V" obtained from the color difference signals B-Y and R-Y.
The U signal is obtained from the B-Y signal by a level reduction by a factor of 0.493 and is limited to 1.3 MHz in video bandwidth. The V signal corresponds to the R-Y signal, but is reduced in level by a factor of 0.877 and is also limited in bandwidth to 1.3 MHz.
This method was developed with the introduction of PAL and is used in PAL video and PAL television. The background is the backward compatibility of color signals for black and white televisions.YPbPr color model via the color difference signals. The Pb signal is approximately 1.15 x the U signal and the Pr color signal is 0.81 x the V signal.
In video compression, the data of the color difference signals U and V can be reduced using color subsampling.