A MODIFIED ALGORITHM FOR LOW-POWER IMAGE CODING AND DECODING

In this paper, a modified scheme for small memories and low-power image and video coding is presented. It is based on vector quantization. In 1998, K. Masselos uses a small codebook, and by using simple but efficient transformations to the codewords during coding procesa the small codebook is extended, thus compensated for the quality degradation intro- duced by the small codebook size. In this way, the power consumption is reduced. Compared to the scheme proposed by K. Masselos, we store the quantized DCT coefficients of codewords in the codebook instead of the codewords itself, and the distortion calculation is performed in the DCT field respectively. Because we use only a part of coefficients to calculate the distances, the distortion calculation is simplified. Furthermore, we modified the way of designing the small (odebook; the possible redundancy in K. Masseloss codebook is eliminated.