A fast recursive pruned DCT for image compression applications

This paper presents a recursive algorithm for computing the pruned DCT with a structure that allows the generation of the next higher order pruned DCT from two identical lower order pruned DCTs. The implementation of the proposed algorithm does not require bit-reversal shuffling, coefficient inversions or divisions. To illustrate the usefulness of the proposed recursive pruned DCT algorithm, we utilizes it to compress images using the JPEG algorithm. The proposed pruned DCT algorithm improves the compression ratio and reduces both the complexity and execution time of the modified JPEG algorithm