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Color Theory & Perception
CIE 1931 chromaticity · metamers · opponent channels · color blindness simulation
CIE 1931 Chromaticity Diagram
x = X/(X+Y+Z), y = Y/(X+Y+Z)
Spectral locus: pure wavelength colors
Purple line: non-spectral colors
D65: standard daylight illuminant
RGB Mixer
Red
200
Green
100
Blue
50
XYZ: —
xy: —
Lab: —
Hex: —
Opponent Channels
L-M (red-green)
S-(L+M) (blue-yellow)
L+M (luminance)
Color Blindness
Spectral Power Distribution
Blackbody
Fluorescent
LED
Narrow
Flat
Metamers: different SPDs → same XYZ color.
Δ above with different SPD type.
Metamer comparison: same perceived color, different spectra