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% rgb2dac %%
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DAC = rgb2dac(RGB, invGammaTable)
RGB is the linear intensity of each gun, in the form of [r g b]. r, g, or b
can be a matrix, a vector, or a number. RGB should be in the range [0 1].
DAC contains the frame buffer values of the 3 color planes, in the form
of [DAC_r DAC_g DAC_b]. To separate the 3 planes, use GetPlanes.
The DAC values returned are in the range [0, 1].
invGammaTable -- the look up table to go from linear RGB to DAC
If it has one column, all RGB values are changed according to this
If it is a scalar number, raise the RGB values to 1/invGammaTable.
If GammaTable is not given, use a default scalar of 1/2.2.
Xuemei Zhang
Last Modified 4/29/97