COMPRESSION CODING METHOD AND DECODING METHOD OF COLOR IMAGE, AND COMPRESSION CODING DEVICE AND DECODING DEVICE OF COLOR IMAGE

摘要

PPROBLEM TO BE SOLVED: To provide a compression coding method and a decoding method of a color image by which an information amount during transmission, display, storage, etc. of color image information can be considerably reduced. PSOLUTION: Color separation is applied to a color original image 1, and color difference components are compressed and coded to luminance components by a JPEG encoder 2 with an electronic watermark function by electronic watermarking in accordance with a key file 3 wherein a rule for embedding color difference components into luminance components is described. An obtained output image is a monochromatic JPEG image 4 having the color difference components concealed, and this image is inputted to a JPEG decoder 7 with an electronic watermark function, and the electronic watermarking of color difference signals is released in accordance with an electronic watermark release rule specified in the key file 3, whereby a color image 8 is restored. PCOPYRIGHT: (C)2008,JPO&INPIT