Abstract: A digitized image compression system employs several different compression techniques to compress the luminance and chrominance information and encodes the selected technique “on the fly” by inserting selected escape and header codes into the encoded data stream. More particularly, during compression, each image is divided into non-overlapping contiguous regions, referred to hereinafter as blocks and image data is compressed on a block-by-block basis. Each encoded block begins with a one-byte header that indicates, in conjunction with a previous escape code, the compression technique which was used to encode the block. Therefore, interpretation of the encoded data is a hierarchical process: the escape codes indicate a stream interpretation mode which, in turn, determine the meaning of header values which follow and the header values, in turn, determine the meaning of the encoded data in each block.

Abstract: A system and method for generating a universal palette and for mapping the color space for an original image into the universal palette for compression. The universal palette utilizes a one byte three color format type allowing reservation of shades for a presentation layer of an operating system for the digital computer. The three color components for a pixel in an original image are then mapped to a specific palette having the one byte format. Mapping depends in part, upon the original component values. Where a color component does not correspond closely to a color component in the universal palette, it will have a value falling between first and second color values in the universal palette. The component is mapped to either the first or second color value on a pseudo-probablistic basis.