<title>Wavelet transcoding of block DCT-based images through block transform domain processing</title>

Abstract

In this paper, we propose a method of efficient computation of wavelet coefficients from DCT-based coded image/video signals. Block Transform Domain Filtering(BTDF) is well suited for transcoding of such data. First direct transform domain processing removes the necessary of inverse transform. Second, the number of nonzero elements in the blocks are significantly smaller than spatial domain. Therefore, the amount of computation can be reduced accordingly. Finally, the block processing algorithm provides a parallel processing method. Hence a fast implementation of the algorithm is well suited.