| 摘要 |
<p>PROBLEM TO BE SOLVED: To attain statistic encoding for color image data by filtering the color image data while evaluating a color value of surrounding pixels with respect to each target pixel in the color image, dividing the color image into a pixel block array consisting of pixel blocks, and encoding the image based on a fixed bit number denoting each target pixel in each block. SOLUTION: In order to filter data relating to each target pixel, data of pixels surrounding each target pixel are averaged. However, this is applied when each target pixel has a pixel value within a prescribed range. An averaged output is an average of two respective pixels A, B, D, E around a target pixel C with respect to raster lines. In the case of compressing a plurality of levels, blocks of the image data that are classified based on uniform saturation and patterns are processed according to the block sequence or the level sequence. In the case of adopting the block sequence, adaptive compression or selective processing of a block at a top level is available. In the case of the level sequence processing, the blocks are processed in the order of all blocks at the top level, each block at an intermediate level and blocks at a minimum level. An image with high resolution can be displayed as the blocks are being decoded from those at the maximum level toward those at the intermediate level.</p> |
