Subband Coding of Color Images

Abstract

The digital encoding of color images has received considerably less attention than the coding of monochrome images. And although most image coding algorithms indeed concentrate on the case of monochrome images, it is clear that color pictures are generally far more preferred and appreciated than monochrome images by the human observer. Modern image compression schemes therefore will all be suitable for color images, while for typical monochrome applications such as medical image data storage and the transmission of newspaper pictures, they will also be compatible with monochrome image compression. For example, both in present analog color television (NTSC/PAL/SECAM) and in the color television standard for digital television (the CCIR recommendation 601, [8]), the system is compatible with monochrome systems. Thus we will first discuss the encoding of monochrome images using subband coding. Then we will extend the technique to color images.