PATTERN CODING SYSTEM AND DECODING SYSTEM AND CODER AND DECODER EMPLOYING THE SYSTEM

摘要

PROBLEM TO BE SOLVED: To improve the storage rate in the case of storing codes and to enhance the efficiency of code transmission by reducing the code quantity of pattern coding. SOLUTION: A pattern extract section 3 extracts a pattern in image data to obtain an extracted pattern. A storage/match discrimination section 6 stores an extracted pattern as a storage pattern to assign an index specific to the storage pattern and compares the extracted pattern with the storage pattern stored in the past to discriminate whether or not the pattern is the same pattern. When the same pattern, the storage/match discrimination section 6 provides the output of position data in a library in place of index data and uses a difference between offset position data of the extracted pattern and offset position data of the stored pattern for an offset position difference data to provides the output of it to a coding section 10 and provides the output of a bit map and offset position data of the extracted pattern to the coding section 10 when the same pattern is not in existence in the library.