A Rate Control Scheme for High Efficiency Video Coding Using a New Rate-Quantization Model

In this paper, a rate control scheme is proposed based on a new rate-quantization model for emerging HEVC video codec. Unlike conventional video codecs, the HEVC has hierarchical quadtree structures with deeper coding depths. In our observations in HEVC codec, significantly different characteristics of transform residues are shown according to the CU depth levels. Motivated the observations, we categorized the CU depth levels into three type, which include low-, mediumand high-texture CUs. The Laplacian probability density functions for each CU category are independently made for the rate-quantization model. With the proposed rate model, more accurate rate control can be achieved owing to more adaptive and accurate rate estimations. Experimental results shows that the proposed rate control scheme achieves PSNR improvements by average 0.16dB, compared to the single PDF based scheme. Furthermore, the proposed scheme shows the more stable bit generation to target bits for each frame. Buffer levels are quite close to the target buffer levels.