User Guide

302 Appendix E, Digital Compression
The difference between 4:2:2 and 4:2:0 is their method of vertical sampling. 4:2:0 YCbCr
samples every other line vertically (between lines 1 and 2, skips the space between lines 2
and 3, and then samples again between lines 3 and 4):
4:2:2 YCbCr, on the other hand, samples every line vertically:
Note: The 4:2:2 and 4:2:0 numbers refer to the amount of color data shared between
groups of four pixels. YCbCr video does not provide as much flexibility as RGB in
determining exactly what color each pixel is. YCbCr does, however, provide a lot of colors
with fewer bytes required for each pixel (two bytes per pixel for YCbCr vs. three bytes per
pixel for RGB, a 30% reduction in data size.)
SCAN
LINE
1
2
3
4
5
CALCULATED CB, CR SAMPLE
Y SAMPLE
SCAN
LINE
1
2
3
4
5
CALCULATED CB, CR SAMPLE
Y SAMPLE