Chroma Subsampling - History

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:

    What you don’t understand is that it is possible to be an atheist, it is possible not to know if God exists or why He should, and yet to believe that man does not live in a state of nature but in history, and that history as we know it now began with Christ, it was founded by Him on the Gospels.
    Boris Pasternak (1890–1960)

    The history of all hitherto existing society is the history of class struggles.
    Karl Marx (1818–1883)

    History ... is, indeed, little more than the register of the crimes, follies, and misfortunes of mankind.
    But what experience and history teach is this—that peoples and governments have never learned anything from history, or acted on principles deduced from it.
    Georg Wilhelm Friedrich Hegel (1770–1831)