| 摘要 |
PURPOSE: To set a binarization threshold level optimum to all blocks by storing binarization threshold level of each block whose binarization threshold level has already been decided as block information and applying binarization to a received image through the use of the binarization threshold level. CONSTITUTION: Tentative binarization threshold level of each block and discrimination result of presence of an object are written in a block information storage means 4 for each block line in the row direction for received image data divided into plural blocks. At first the write is made for two block lines and the processing is restored to one preceding block line, the binarization threshold level of each block of the line is decided by referencing the content of the means 4, the decided binarization threshold level is written in the means 4 and a concerned block is binarized. Then tentative binarization threshold level of each block and discrimination result of presence of an object are written in the block information storage means 4 for each block of one succeeding line, the processing is restored to one-preceding line, the binarization threshold level of the line is decided by referencing the content of the means 4 and written in the means 4 and the binarization is processed for the concerned block. The processing above is repeated. |
