REMINDER, Today's BISC Seminar, 17 April 1997, Color Computer Processing

Lotfi Zadeh (
Wed, 23 Apr 1997 10:06:27 +0200

Computer Color Processing

BISC Seminar

Dr. Gabriel Marcu
Apple Computer
1 Infinite Loop
Cupertino, CA 95014

17 April 1997
310 Soda Hall


The lecture will try to give an overview of the color related concepts used
in the computer world today. The lecture is intended to emphasize the
differences between the human color perception and the representation of
color in the computer and to show the difficulties to make the computer to
"see" the color like a human observer.

The lecture is structured in three parts. The first part will introduce the
basic definition and phenomena related to the color perception: tricromatic
color vision, methamerism, mechanism of color generation, surround effect,
adaptation. For consistent color specification and comparison, color spaces
are introduced. The course will try to illustrate the relationship between
different specification of color: CIEXYZ standard tristimulus space, RGB for
computer, HSV and HSL reflect the perceptual attributes of color, CMYK for
printing reproduction.

The second part of the lecture will discuss problems related to color
analysis for extraction of information from color images. The 3D histograms
and clustering methods will be illustrated using a PC based application. The
clustering methods are illustrated in one practical application: hand drawn
color layer extraction from blue print documents.

The third part will describe the difficulties of consistent color
reproduction. The dependence of color with the reproduction device is
illustrated. The color gamut concept and the device independent color spaces
are introduced. The color management approach to consistent color
reproduction is discussed. A computer application that displays color gamuts
of several CRTs and printers is demonstrated.