为了进一步提高图像编码效率，利用多小波子带上各个分量间的相关性以及分量间能量分布的特点，提出了一种SPIHT改进算法。该算法是根据高频子带第1分量无效值的分布来预测其他3个分量上不重要系数的位置信息，由于减小了无效集判别过程中的扫描范围，从而可加快编码速度。实验结果表明，该算法既提高了编码效率，又保持了压缩性能。

This paper exploits the distribution of energy and correlation between various components of sub-bands and modifyies the SPIHT algorithm. In this scheme, insignificant coefficients of first component in high-frequency sub-bands that correspond to the same spatial location in other components can be used to reduce the scanning scope in the process of invalid set discrimination. Both theoretic analysis and experiment results confirm good compression performance and low complexity at the same time.