A model-based rate allocation mechanism for wavelet-based embedded image and video coding

In wavelet-based embedded coding for still images and/or videos, a trade-off between scalability and coding efficiency is achieved via layered-packetization of the embedded bitstreams optimized for several target operating bitrate points. This process is called rate allocation (tier-2 coding). The typical rate allocation mechanism is formulated as a rate-distortion optimization problem and a simple search method with slow convergence rate is used. A highly efficient model-based rate allocation mechanism is proposed. The algorithm is base on the adaptive analysis of the relationship between rate and distortion of the image/video data. Experiments conducted on a scalable video codec show that the time to obtain the optimal solution is greatly reduced. The techniques can be applied to various wavelet-based embedded image and video coding schemes, such as JPEG2000 and scalable video coding.