Preparing IceBreaking party

SCIA 2005 HighLights

IceBreaking party

Conference Banquet in
Valamo Monastery

Post-conference tour to St.Petersburg

Spectral Color Research

Traditional color science has been dominated by the models of human color vision. These models assume a three dimensional representation of all colors. In addition to the color research, this three dimensional approach is dominant in the standard technical realizations of color measurement, imaging, and display. Some of the most common coordinate systems are RGB and Lab color coordinate systems.

It has turned out that this traditional approach of three dimensional color management is not sufficient in general color science nor in many applications. This is true for point color measurements and as well as color images.

A new emerging technology, spectral imaging, is developing rapidly for needs of accurate color measurement, analysis, and digital color management. This spectral approach makes it possible to e.g. avoid a common problem of metamerism (two colors look the same under certain illumination, but different under another) or compute a real colors of an object under different illuminations.

This spectral approach to color is developing not only in theory, but also technically. At the moment there are commercially available spectral cameras and on laboratory level both multiprimary video cameras and multiprimary displays. The memory requirements for raw images are very high for spectral images. A comparative list of raw image file sizes are shown below. Each component is assumed to require one byte.

256x256 pixels 512x512 pixels Grey-level image 66 kB 262 kB

color (RGB-) image 197 kB 786 kB

spectral, 20 nm resol. 1 MB 4 MB

spectral, 5 nm resol. 4 MB 16 MB

One can easily see that an efficient use of the spectral images requires efficient compression and processing methods.

The use of spectral color analysis and spectral images is increasing also in many applications. This is due to the rapidly developing techniques. The applications include on-line paper color monitoring, digital archives of paintings, food and plant quality control, quality control in plastic industry, and real color reproduction in e-commerce.

In this tutorial course, the basics of spectral color science will be given and methods for spectral image analysis and compression will be studied. Also, there will be an overview to the present application fields. The course include demonstrations to show the need of color management, hands-on exercises where we take some spectral images, do some analysis, and modify them to look realistic under different illuminants.

Here is an introductory material for the course. The tutorial material include electronic copies of the lecture notes and some sample spectral images for self study after the course.


Jussi Parkkinen is a professor and the Head of Department of Computer Science at the University of Joensuu, Finland. He specializes in spectral color image analysis, pattern recognition and molecular computing. He received his B.Sc. in physics in 1979, his M.Sc. in medical physics in 1982 and his Ph.D. in mathematics in 1989, all from the University of Kuopio, Finland. In 1989-1990 he was a visiting researcher at The University of Iowa, IA, USA, in 1990 a visiting professor at the University of Saskatchewan, Canada, in 1991-1992 professor and the Head of Department of Computer Science in the University of Kuopio, Finland, and in 1992-1998 professor of Information Processing, in 1995-1998 dean of the Deapartment of Information Technology at the Lappeenranta University of Technology, Finland. In 1995-1999 he was the chairman of the Finnish Pattern Recognition Society and he is a fellow and a member of the governing board of the International Association of Pattern Recognition (IAPR). He is the chairman of the CIE TC8-07 technical committee on Multispectral Imaging.

Pattern Recognition Society of Finland

The International Association for Pattern Recognition