A Fast Image Encoding Algorithm Using Vector Features

Vector quantization (VQ) is an efficient technique for image compression. However, one of the most serious problems of VQ is the heavily computational load for searching the closest codeword to the input vector in the codebook. To overcome this problem, we propose a simple and fast encoding algorithm for vector quantization. The algorithm uses three significant features of a vector, that is, the norm, its projection angle to a reference line and the variance, to reduce the search area and accelerate the search process. This algorithm allows significant acceleration in the encoding process. Experimental results are presented on image block data. These results show that the proposed algorithm performs better than the previously known algorithms.