| 摘要 |
<p>PROBLEM TO BE SOLVED: To send an image with a high image quality even when a coding compression rate is high and a transmission data quantity is small by sending code data of each bit plane of a high-order bit group and code data of each bit plane of a low-order bit group altogether as one set of multi-value image data. SOLUTION: A multi-value scanner 4 reads an original image with a prescribed resolution and provides an output of the read image data as multi-value data. Then a coding decoding circuit 7 applies coding compression to the multi- value data and decodes the multi-value image data subjected to coding compression into original multi-value image data. Then the image of high-order 3-bit in 8-bit original image data is subjected to bit plane coding directly and least significant bit data of the low-order 5-bit data are aborted. Then the remaining other 4-bit data are subjected to dither binarization processing and the obtained low-order bit plane data are used for one bit plane, then a high image quality image is sent even when the coding compression rate is high and the transmission data quantity is small.</p> |
