Rate and Distortion Modeling of CGS Coded Scalable Video Content
In this paper, we derive single layer and scalable video rate and distortion models for video bitstreams encoded using the coarse grain quality scalability (CGS) feature of the scalable extension of H.264/AVC. In these models, we assume the source is Laplacian distributed and compensate for errors in the distribution assumption by linearly scaling the Laplacian parameter . Moreover, we present simplified approximations of the derived models that allow for a run-time calculation of sequence dependent model constants. Our models use the mean absolute difference (MAD) of the prediction residual signal and the encoder quantization parameter (QP) as input parameters. Consequently, we are able to estimate the residual MAD, bitrate, and distortion of a future video frame at any QP value and for both base-layer and CGS layer packets. We also present simulation results that demonstrate the accuracy of the proposed models.