Spectral Colors to RGB, Tone Mapping
Joshua Andersen
CS6650 Fall 2002
The following images were created by finding the CIE tristimulus values XYZ that match the function L(x,y,lambda)
= (y/n_y) delta(lambda - (420(x/n_x) + 380)), using the CIE color matching functions x-bar, y-bar, and z-bar.
The XYZ color-space values were then tone-mapped such that Y was in [0,1], and then
converted to the RGB color space using Pete Shirley's conversion matrix:
2.5623 -1.1161 -0.3962
-1.0215 1.9778 0.0437
0.0752 -0.2562 1.1810
Varying k changes the brightness of the image.
K = 0.1
K = 0.4
K = 0.7
K = 1
K = 3
K = 5
K = 10
K = 25
K = 75
K = 125