| 摘要 |
PROBLEM TO BE SOLVED: To efficiently compress an original image and to restore the original image suppressing deterioration in its image quality. SOLUTION: The inside of the image compressor 10 is provided with a reduced image generating section 11, a conversion mode setting section 12, a fluency conversion section 13, a difference generating section 14, a DCT arithmetic section 15, a code quantity calculation section 16, an optimum mode selection section 17, and a Huffman coding section 18. The reduced image generating section 11 reduces original image data to generate reduced image data. The fluency conversion section 13 generates magnified image data from the reduced image data according to a conversion mode set by the conversion mode setting section 12 and the difference generating section 14 calculates a difference between the original image data and the magnified image data. The DCT arithmetic section 15 applies DCT arithmetic processing to the difference and the code quantity calculation section 16 calculates a code quantity of a difference DCT coefficient. The optimum mode selection section 17 decides in advance a conversion mode with the least code quantity among a plurality of the conversion mode and the difference DCT coefficient in response to the optimum mode is Huffman-coded. |
