A low memory degree-k zerotree coder

Image compression based on zerotree coding such as set-partitioning in hierarchical trees (SPIHT) yield very good performance. SPIHT uses bit-plane coding where the wavelet coefficients are scanned at every encoding pass. This requires a lot of memory space since the whole image has to be stored for the process of set-partitioning coding. In this paper, a low memory degree-k zerotree wavelet coding scheme is presented. The proposed algorithm uses a new tree structure with a lower scale of wavelet decomposition. Besides this, the degree of zerotree tested is tuned at each encoding pass. Simulation results show that our proposed coding scheme gives an almost equivalent performance as the SPIHT algorithm and achieves a memory reduction of 93.75% compared to SPIHT.