Indicatory data extension method and indicatory data compression extension method, the extension processing which extends the indicatory data extension device and the compressed

摘要

PPROBLEM TO BE SOLVED: To make the compressibility higher than that of a conventional method. PSOLUTION: A compressing method includes a reduction processing for reducing image data 1 before compression, a division processing for dividing the image data compressed through the reduction processing into a plurality of blocks, and a compression processing for compressing the image data divided into the plurality of blocks in block units. The division processing is processing for dividing the image data so that display data at border parts between blocks are held in two adjacent blocks in common. A display data expanding method of expanding the compressed data having been compressed by the compressing method includes an expansion processing for expanding the data having been compressed in the block units reversely to the compression processing, an enlargement processing for enlarging the data expanded through the expansion processing, and a composition processing for putting together data in the block units after the enlargement processing. PCOPYRIGHT: (C)2007,JPO&INPIT