图像渐进传输、多质量服务以及图像数据库浏览等多分辨率环境下的多媒体应用导致了图像可分级编码思想的产生。本文首先对图像可分级编码的概念进行了解释，然后对JPEG和JPEG-2000中的图像可分级情况进行了讨论，并以实现图像可分级编码的工具和方法为线索，对基于小波、DCT和匹配追踪（marching pursuit）的图像可分级编码的发展情况进行了分析和讨论，同时对3类可分级编码技术进行了比较，并对其发展趋向和在视频可分级编码中的推广情况进行了讨论。最后对图像编码技术的发展方向进行了展望。

The multimedia applications in a multiresolution environment, such as progressive transmission of image,image database browsing, etc. , arise scalable image coding algorithm. This paper first explains the concepts of all kinds of scalable image coding, and gives an analyse for the scalable image coding algorithms in JPEG and JPEG-2000. Secondly, an overview of major methods already used or under investigation for scalable image coding based on Wavelet, DCT and Matching Pursuit with the scalable coding tools and methods is introduced, and the decoder performance comparison among the three kinds of scalable coding is given. In addition, the trend of the three kinds of scalable coding and their extension in video scalable coding is discussed. Finally, the future development of image coding is also analyzed and conjectured in the paper.