IMAGE COMPRESSION DEVICE AND IMAGE DECOMPRESSION DEVICE, AND COMPUTER-READABLE RECORDING MEDIUM RECORDED WITH PROGRAM FOR MAKING COMPUTER IMPLEMENT IMAGE COMPRESSION METHOD AND IMAGE DECOMPRESSION METHOD

PROBLEM TO BE SOLVED: To enable an image to be coded without causing visible color shifts. SOLUTION: A multiple-resolution image compression device 20 comprises a color space conversion unit 34 for converting three input image data of RGB into image data of a YUV space; a resolution determination unit 38 for determining the resolution of image data of a color space for each block of each image data; a resolution information coding unit 42 for coding resolution information; a data-preparing unit 44 for preparing data in which each block of the image data of the color space is contracted to a half, as well as non-magnified data based on the resolution information; a contracted data coding unit 48A for JPEC-coding the contracted data; same size data coding unit 48B for JPEG-coding non-magnified data; and a binding unit 50 for binding the JPEC-coded resolution information, contracted data, and non-magnified data to a single piece of data. COPYRIGHT: (C)2005,JPO&NCIPI