A multiplication-free transform for image compression

In this paper, we propose an efficient 8 times 8 multiplication-free transform operator for image compression by appropriately introducing some zeros in the 8 times 8 signed DCT matrix. We also develop fast algorithms for the computation of the proposed transform as well as for its inverse. Compared to the existing 8 times 8 approximated DCT matrices, it is shown that savings of 12.5% in the number of additions can easily be achieved using the proposed transform operator without noticeable degradations in the reconstructed images. We also present simulations on some standard test images to show the efficiency of the proposed transform in image compression.