A new continuous tone, direct thermal full color hardcopy system called "TA"(Thermo-Autochrome) system has been developed. Its key technology mainly resides in the new thermal media "TA paper"which contains all the chemical components needed to develop three primary colors (cyan, magenta and yellow) in its multi-layer structure. A full color image is formed in the following steps. The thermally most sensitive, yellow color forming layer is first recorded by lower energy and then fixed by near UV light. The thermally midway sensitive, magenta color forming layer is then recorded by higher energy and fixed by UV light. and finally the lowest sensitive, cyan color forming layer is recorded by highest energy. The TA system has a big advantage over conventional hardcopy systems of accompanying no waste such as ink ribbons or ink cartridges. This paper describes the mechanism of image formation and the basic configuration of digital color printer. We will also compare TA with D2T2 and consider the future of this new system.

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Here we propose the "conditional polynomial"which is specified with some given conditions. By specifying x, y coordinates of points passed through, we can control the shape of the polynomail curve very intuitively. So it is specially useful for linearization of non-linear input-output function, and also for color image gamma correction and active color control.

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We developed a color management system "ColorFusion2"to achieve color WYSIWYG on Windows95. ColorFusion2 is available by an interface provided by Image Color Matching, which is loaded as a standard system in Windows95,and supplies own APIs to application software. Device profiles for ColorFusion2 are based on ICC Profile Format Ver.3.2 which has become de facto standard. With ColorFusion2 and ICC profiles, color WYSIWYG between different color image devices can be achieved. We developed ICC profile library ICPLIB 1.0 to utilize ICC profiles and opened it to the public as free software.

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The standard encoding scheme JPEG shows an excellent performance for still pictures in terms of coding efficiency. In the JPEG system, however, higher frequency components are not used to increase compression efficiency. Therefore, the reconstructed picture quality for pictures including edges such as characters is visually not good. In this paper, a new encoding scheme for high definition images with text and photograph is presented. The proposed algorithm consists of the following two processes : (1) Character segmentation (2) Adaptive encoding for both character regions and back ground region. Computer simulation results using several pictures shows 37.6 dB at 1.01 bits/pel on average while 26 dB at 1.0 bits/pel in the performance of JPEG. From the experimental results, the prospects of using this method can be considered.

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In the stereo vision system, one of the most important problems is to obtain the corresponding points between the left and right images, because this process has direct effects upon the measurement accuracy. In this paper, a stereo matching algorithm based on isodensity lines and a new method for interval corresponding estimation is proposed. The proposed method consists of two stages. In the first stage, important corresponding points (high confidence points) are sought using the similarity of isodensity lines extracted from the left and right images, then one-to-one correspondence for the pixels existing in the intervals derived from the important points is obtained in the second stage. From the computer simulation using dummy head, adequate results were obtained even for the forehead where isodensity lines can not be extracted in conventional method.

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