[Tig] When to use 444RGB or 444YUV for Dual link monitoring in a DI

[Bob Friesenhahn]

On Thu, 9 Aug 2007, adrian hauser wrote:
>
> Hi Simon,
> Are you sure the RGB cube sits inside the YCbCr cube?

YCbCr is based on RGB.  By definition, YCbCr can at best match RGB.  A 
math transform is used to compute a luminance value, and then blue and 
red difference values from luminance, just as you say.

Simon sez that there is "not a loss of available colour" but "loss of 
color" seems open to definition.  The range of color may not be 
altered much but YCbCr is missing discrete colors which are supported 
by the same number of bits of RGB. A colorist's trained eyes would 
likely notice the difference in many cases.

Bob
======================================
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/