Segmented image coding of palettized images

This paper addresses the efficient high-compression coding of palettized color images. The most common methods for the lossy compression of color images rely on independent block oriented transform coding of the three or four color components. These techniques do not make use of the high redundancy of the color components and introduce some very undesirable errors at high compression, in particular block distortion. We present an efficient and original technique to code color images with a small number of colors. This is an important class of images in multimedia applications. The technique codes the according luminance image using an existing segmented image coding method for monochrome images. The color information is independently represented in a bit map. The method does not rely on the commonly used color separation and shows a far better subjective image quality than JPEG at high compression