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To quantify human visual system characteristics to carry out rate controlling efficiently, this paper presents a new macroblock (MB) layer rate control algorithm for multi-view video coding (MVC) by improving quadratic rate-quantitative (R-Q) model based on the just noticeable distortion (JND) model. Firstly, the pixel-JND value of color image in multi-view video is stroked according to the related research in order to be used in the MB layer rate control. The proposed algorithm includes view layer, GOP layer, frame layer and MB layer, respectively. In the MB layer, the JND of the MB and mean absolute difference (MAD) in the quadratic R-Q model are firstly analyzed, the MAD is re-defined as perceptual MAD according to the JND with a pixel adjustment factor, and then QP of MB is computed through the re-defined quadratic R-Q model. Finally, a frequently-used image quality metric, peak signal-to-noise ratio (PSNR), is similarly re-defined as perceptual PSNR according to the JND. Experimental results show that the proposed algorithm can obtain higher image quality while precisely controls the bitrates. Moreover, the proposed algorithm not only can achieve better subjective quality, but also save the bitrates about 14.47% ~ 32.13%.

To investigate the impact of buffer on stereoscopic video coding, three rate control (RC) methods were presented. In the separate buffer RC method (SBRC), left and right views achieved rate controlling using respective buffer in their own given target bitrates. The united buffer RC (UBRC) and its improved united buffer RC (I-UBRC) methods were both in a given total bandwidth and the united buffer, they were performed on three levels, namely stereoscopic group of pictures (SGOP) level, stereoscopic frame (SFrame) level and frame level. The united buffer RC method adopted asymmetric-quality bits allocation based on the mean absolute difference (MAD) of left and right images in frame level. The improved united buffer RC method took relative complexity and importance into account to allocate bits rationally in SFrame level. Experimental results show that the proposed three methods can accurately control the rate to satisfy the requirements of stereoscopic video coding, and the coding efficiency of the improved united buffer RC method is the highest.

Rate control is one of important tools in multi-view video coding (MVC). This paper presents a new rate control algorithm for MVC by analyzing the rate allocation proportion among different types of views. The proposed algorithm is performed on three levels, that is, view level, group-of-pictures (GOP) level and frame level. Firstly, we reasonably allocate bit-rate among views based on the statistical analysis in the view level. Then, in the GOP level, the initial quantization parameter (QP) of each GOP is set according to the QP values of B frames. Finally, the frame complexity is used to regulate the target bit for each frame. Experimental results show that the proposed algorithm can accurately control bit-rate to satisfy the requirements of multi-view video systems.