Issues of Quality and Multiplexing When Smoothing Rate Adaptive Video

We have proposed a smoothing and rate adaptation algorithm–SAVE (Smoothed Adaptive Video over Explicit rate networks)– for transport of compressed video over rate-controlled networks. SAVE attempts to preserve quality as much as possible, and exercises control over the source rate only when essential to prevent unacceptable delay. In order to understand the impact on quality of rate adaptation, we have evolved the quality metrics typically used to evaluate the efficacy of mechanisms to transport video. In this paper, we investigate the dynamic nature of rate reduction: any prolonged impairment is likely to be noticeable. We study the sensitivity of SAVE to its parameters and network characteristics. Finally, the utility of the proposed scheme is measured by its ability to multiplex a large number of streams effectively. Our evaluations are based on experiments with 20 traces of entertainment videos using different compression algorithms. Keywords—Compressed Video, Rate Control, Smoothing, Multiplexing.