Rec. 601

CCIR 601 is a standard published by the CCIR for encoding interlaced analogue video signals in digital form. It includes methods of encoding 525-line 60 Hz and 625-line 50 Hz signals, both with 720 luminance samples and 360 chrominance samples per line. Regardless of the frame rate, the luminance sampling frequency is 13.5 MHz, giving a data rate of 165 Mbit/s. The colour encoding system is known as 4:2:2, that being the ratio of Y:Cb:Cr samples (luminance data:blue chroma data:red chroma data).

The CCIR 601 signal is effectively a digitally encoded analog component video signal, and thus includes data for the horizontal and vertical sync and blanking intervals.

In each 8-bit luminance sample, the value 16 is used for black and 235 for white, to allow for overshoot and undershoot. The Cb and Cr samples use the value 128 to encode a zero value.