A new quantization improvement of SPIHT for wavelet image coding

Abstract

The SPIHT (set partitioning in hierarchical trees) algotithm has attracted great attention in recent years as a technique for image coding. Not only does it give good objective and subjective performance, it is also simple and efficient. In this paper, we investigate the problem of how to quantize the wavelet coefficients in the lowest frequency subband with multi-scalar method. A novel wavelet image coding algorithm using multi-scalar quantization based on SPIHT is proposed. First, in the higher bit plane, this algorithm only quantizes the wavelet coefficients in the lowest frequency subband. Then it quantizs other ones by uniform scalar. Experiment results have shown the proposed scheme improves the performance of wavelet image coders. In particular, it will get better coding gain in the low bit rates image coding. © 2009 Springer Berlin Heidelberg.