Visual Illustration and Experiments
CIECAM 97 is a model of color appearance for surface reflection.
In this section we make an attempt at making interesting visuals
and doing experiments using a monitor. CIECAM is not meant for
use with light sources such as monitors, so these are just our
best attempts at accurate illustrations. In addition, these
illustrations were calibrated for monitors in our Image Systems
and Engineering Lab at Stanford.
Perceptual Ramps
To get an idea of what each of these color appearance parameters
meant (JCh QMh etc), we wrote scripts that generate
linear ramps in these perceptual dimensions. These ramps can
be chosen to go through any prespecified RGB color.
ramp_jc.m
generates linear ramps in JCh coordinates
ramp_qm.m
generates linear ramps in QMh coordinates
The following are examples of color ramps for J (lightness), C
(chroma), and h (hue)
respectively. The black bar represents the position of
50% gray along the color ramp.
J: 
C: 
h: 
Color Matching
We also tried to do a small matching experiment, given two background
colors, and the color of one patch in one background, we try to use the
color appearance model to pick an appropriate color patch for the other
background to produce a match. Color appearance models were not designed
for this problem, and we attacked it by using the Yb parameter to get
background information into the conversion.
match.m generates color matches
Below is an example of an approximate color match:
Krishna S. Nayak /
nayak@stanford.edu
Copyright © 1998