CODER FOR MULTI-COLOR IMAGE, ITS METHOD, DECODER FOR MULTI-COLOR IMAGE AND ITS METHOD

摘要

PROBLEM TO BE SOLVED: To greatly improve the processing speed by remarkably reducing an arithmetic amount for sorting required for head movement processing in 2-dimension color sequence conversion, that is, the newest appearance list generating processing, and to allow the method to use a peripheral pixel generating means such a line buffer with a low capacity. SOLUTION: The multi-color image coder 1 or the like has a color sequencing table 23 that is synthesized from a high-order 2-dimension color sequence table 20 for 2-dimension surrounding pixel data and a low-order color sequencing linear color sequence table 22 that is generated by the newest appearance table generating operation that moves up the color sequence of a color symbol corresponding to color pixel data received newest up to the highest. Then the coder 1 provided with a paper-tablet generating means 5 that divides an object image being an object for coding/decoding into a paper-tablet with a lateral width of a limited pixel number and with a paper-table synthesis means to code sequentially inside of each paper-tablet or to decode data into paper-tablet.