Pattern matching coding device using pattern matching and coding method therefor

A coding method for a pattern matching coding device, wherein:

• inputted first image data is accumulated in a memory;
• second image data of a necessary part is fetched from said memory by a boundary tracing portion and a mark is cut off;
• a first mark larger than a predetermined value is inputted from said boundary tracing portion and an observation window for observing a pixel on a straight line is moved in said first mark by said boundary tracing portion so as to search for a pixel having a high correlation;
• period information observed in said mark correlation check portion is sent and said first mark is redivided to generate a second mark having a size matching with the period by a mark redividing portion;
• the redivided second mark is accumulated in a library by an accumulative FIFO memory;
• a plurality of said libraries accumulated in said accumulative FIFO memory are referred to and it is determined whether or not there is said library matching with said second mark or a third mark of normal size sent from said boundary tracing portion by a match determining portion;
• said library sent from said match determining portion is determined to match with a fourth mark and sent from said match determining portion together with said fourth mark to a match template;
• only said fourth mark from said match determining portion is sent to an unmatch template;
• and a template value from said unmatch template is outputted as an encoded code and a template value from said match template is outputted as an encoded code by an arithmetic coder.

A pattern matching coding device, comprising:

• a boundary tracer that receives stored image data, cuts off a mark and generates a first output or a second output in accordance with a size of said mark;
• a mark correlator that comprises an observation window that generates a period in accordance with said first output;
• a mark redivider that receives said second output, redivides said mark in accordance with information of said period, and stores said redivided mark;
• a match determining device that determines whether a match exists between said redivided mark or said second output and an old library, and generates a match output in accordance with a result of said determination;
• an accumulator that generates a new library in accordance with said redivided mark or said second output;
• a template that receives said match output and generates a template value;
• and a coder that performs an operation on said template value to generate an encoded output.