Color space conversions
ftp://ftp.wmin.ac.uk/pub/itrg/coloureq.txt
Alan Roberts (Alan.Roberts @rd.bbc.co.uk) and Adrian Ford (ajoecl@westminster. ac.uk) have provided one of the most complete references to color space conversion on the Web. Equations relating to color space and color transforms are presented in an easy-to-read FAQ manner. Topics include an introduction to color spaces, CIE, YIQ, RGB, describing color, color gamuts, and more. This site is well worth a look.