Image compression algorithms such as EZW and SPHT have a high compression rate.In order to they also have spatial scalability, SPIHT algorithm is analyzed.

• 摘要为了能使图像压缩编码算法同时具有较高的压缩率和良好的压缩性能，分析了SPIHT算法，在相同压缩效率的情况下，将其进一步改进，使之具有空间可分级性。