Color image compression by adaptive vector quantization

Vector quantization techniques are currently favored in speech compression. Recently a nonadaptive form of vector quantization was proposed for monochrome image compression. In this paper, color picture compression by adaptive vector quantization is presented. Both spatial and spectral redundancy is exploited. Adaptive vector quantization of color pictures is shown to produce better mean-square-error result than block cosine transform coding, for the same data rate. No statistical image model is assumed. Decoding is a simple process of table look-up, permitting video-rate decoding, thus only a small refresh memory containing the codewords is necessary.