A multiresolutional coding method based on SPIHT

We propose a new method to code still images with multiresolutional coding functionality. This algorithm is based on set partitioning in hierarchical trees (SPIHT) (IEEE Trans. Circuits Systems Video Technol. 6 (3) (1996) 243). We consider each subband as a region of interest and encode it using a region of interest (ROI) coding scheme proposed by the authors. The ROI coding scheme introduced a new parent ROI mask and multiple lists of insignificant pixels and multiple lists of insignificant sets. The proposed multiresolutional coding handles multiple ROIs, each of which corresponds to each subband of the wavelet-transformed image. Although the PSNR performance of the proposed multiresolutional coding at low rates is inferior to the original SPIHT algorithm, it provides multiresolutional coding functionality. We analyzed the rate-distortion performance and the computation time of the multiresolutional coding with respect to various bit-rates. (C) 2002 Elsevier Science B.V. All rights reserved.