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Next: Modifying Saturation Up: 13.2.4 The Color Matrix Previous: Scale and Bias Conversion to Luminance

Converting a color image into a luminance image may be accomplished by scaling each component by its weight in the luminance equation.

L \\
L \\
L \\
R \\
G \\
B \\

The recommended weight values for Rw, Gw, and Bw are 0.3086, 0.6094, and 0.0820. Some authors have used the values from the YIQ color conversion equation (0.299, 0.587, and 0.114), but Haeberli notes that these values are incorrect in a linear RGB color space.[39]

David Blythe