Progressive image compression algorithm based on lattice vector quantization

In this paper, a low computational complexity and high efficiency algorithm for progressive image compression is presented. The image is partitioned into blocks of pixels and a prime- factor 2-D discrete cosine transform (DCT) is applied. Because of the regular structure the DCT algorithm, the coefficients could be computed in groups. Each group of DCT coefficients is then vector quantized by using the pyramid vector quantizer algorithm. Since, the DCT coefficients of each group are allocated with a different number of bits, three PVQs are used with different radii.