A novel approach to joint video coding

It is expected that future delivery of Digital TV signals will use H.264. This paper presents a novel coding scheme for multi-program video transmission in which the channel capacity is distributed among the programs according to the program complexities resulting in a more uniform overall image quality. A complexity bit rate control algorithm based on the Structural Similarity Index (SSIM) is proposed. SSIM metric is presented under the hypothesis that the Human Visual System (HSV) is very specialized in extracting structural information from a video sequence but not in extracting the errors. Thus, a measurement on structural distortion should give a better correlation to the subjective impression. Computer simulations have demonstrated very promising results showing joint coding is able to effectively control the complexity of the multi-program encoding process whilst improving overall subjective compared to independent coding and algorithms based on traditional distortion/quality metrics.