History
Chroma subsampling was developed in the 1950s by Alda Bedford for the development of color television by RCA, which developed into the NTSC standard; luma-chroma separation was developed earlier, in 1938 by Georges Valensi.
Through studies, he showed that the human eye has high resolution only for black and white, somewhat less for "mid-range" colors like yellows and greens, and much less for colors on the end of the spectrum, reds and blues. Using this knowledge allowed RCA to develop a system in which they discarded most of the blue signal after it comes from the camera, keeping most of the green and only some of the red; this is chroma subsampling in the YIQ color space, and is roughly analogous to 4:2:1 subsampling, in that it has decreasing resolution for luma, yellow/green, and red/blue.
Read more about this topic: Chroma Subsampling
Famous quotes containing the word history:
“American time has stretched around the world. It has become the dominant tempo of modern history, especially of the history of Europe.”
—Harold Rosenberg (19061978)
“It takes a great deal of history to produce a little literature.”
—Henry James (18431916)
“As History stands, it is a sort of Chinese Play, without end and without lesson.”
—Henry Brooks Adams (18381918)