Highly scalable image coding for multimedia applications

Abstract

In this paper, we will present a highly scalable wavelet image codec that also achieves good coding efficiency, both subjectively and in terms of PSNR (Peak Signal-to-Noise Ratio). A proposal based on this codec was recently adopted as the texture coding mode in the MPEG4 Working Draft (WD). This codec supports embedded scalability at many SNR levels and spatial resolutions without sacrificing image quality, and the scalability is supported all the way to lossless compression (compressed once, and decoded at multiple resolutions and qualities according to end users’ needs without transcoding). We will introduce in detail the techniques used in the codec. The syntax of the MPEG4 texture coding mode that incorporates this technology will also be introduced. This highly scalable image codec is an enabling technology for many multimedia applications. In this paper, we will describe some of the applications made possible with this technology, such es efficient progressive transmission for web browsing, dynamic rate shaping by network routers, flexible image storage and management in digital cameras, and efficient texture mapping using compressed images in computer graphics.