fix coefficients for detecting brightness

Open lgg opened this issue 9 years ago • 0 comments

The formula using to calculate relative luminance (or brightness): Y = 0.299 R + 0.587 G + 0.114

But it is correct in NTSC (1953) color space only. This formula is deprecated and legacy. Actual color space sRGB significantly different: chromacity diagram.

Correct formula is: Y = 0.2126 R + 0.7152 G + 0.0722 B

The proof of numbers Source — Bruce Lindbloom site See also — Charles Poynton Color FAQ

A lot of work or refactoring is not required. We can simply replace this coefficients.

Jul 03 '16 22:07 lgg