| 摘要 |
PROBLEM TO BE SOLVED: To efficiently obtain image code data having image quality corresponding to a PSNR by realizing the PSNR based on a designation input of the PSNR with respect to a decoded image, obtaining threshold value information with respect to an error in the case of coding an image in a prescribed relation thereto so as to apply coding processing to an input image within a range of the threshold value information. SOLUTION: A CPU 1 uses a program and data or the like in a main memory MM: 2 to conduct each processing and stores an original image and image data that are generated in advance to an original image file 5a and an image code file 5b respectively. First a DC image is generated from a mean value of blocks each consisting of 4×4 pixels obtained by dividing the image data and the mean value of the blocks is subtracted from a pixel value of each block. A base number (=0) or an orthogonal base is obtained depending on whether or not a magnitude of a residual vector obtained from the subtraction above is less than a permissible value or the permissible value or over to code the image data and the residual vector itself is coded when the residual vector obtained from the subtraction above is more than the permissible value and a prescribed condition is satisfied. Thus, objective image quality is obtained efficiently. |
