Texture image compressing device and method, texture image decompressing device and method, data structures and storage medium

A texture image decompressing system, comprising:

• a data processing unit;
• a memory unit;
• and
• a texture image decompressing module which is stored in the memory unit, and which is processed by the data processing unit;
• wherein the texture image decompressing module includes:
• a compressed texture input device inputting a compressed texture into which a plurality of texture images corresponding to a respective plurality of different light source directions and a plurality of different viewpoint directions have been compressed;
• a light source/viewpoint direction input device inputting a viewpoint direction and a light source direction of a decompression target texture image;
• a conversion table extracting unit configured to extract, from the compressed texture, representative intensity maps and color component conversion tables;
• a data extracting unit configured to extract, from the compressed texture, compressed intensity maps corresponding to the inputted viewpoint direction and light source-independent texture compressed images corresponding to the inputted viewpoint direction;
• a light source-independent texture image extracting unit configured to extract light source-independent texture images from the light source-independent texture compressed images by using the color component conversion tables;
• an intensity component computing unit configured to compute intensity components of the decompression target texture image by using the representative intensity maps and the compressed intensity maps;
• and
• a texture image generating unit configured to generate the decompression target texture image by using the light source-independent texture images and the intensity components.