This paper presents a listless variant of modified wavelet block tree coding (MLBTC) algorithm. Wavelet block-tree coding (WBTC) improves the image compression performance of set partitioning in hierarchical trees (SPIHT) at lower rates by efficiently encoding both inter- and intra-scale correlations. The use of auxiliary lists makes WBTC undesirable for hardware implementation as it needs a lot of memory management due to exponential increase of nodes on each pass. The proposed coder named as hierarchical listless block-tree DTT (HLBT_DTT) that combines discrete Tchebichef transform (DTT) with MLBTC exhibits compression performance significantly higher than most of the DCT-based embedded coders and comparable with JPEG 2000, especially at lower bit rates. Further, HLBT_DTT requires only 10% of memory than that of DCT-based SPIHT/WBTC coders.
Enhanced Listless Block Tree Coding with Discrete Wavelet Transform for Image Compression