Rate controlling for color and depth based 3D video coding

Abstract

Rate control is a very important tool for any kind of video coding and transmission. Even though there are many rate control techniques designed for 2D video, not much work has been carried out in this area for 3D video. In this paper, a novel rate control approach for 3D video based on color and depth maps is introduced. The aim of this rate control algorithm is to keep the 3D video quality near constant. Since the 3D video is synthesized from color and depth maps and the final quality of 3D video is more influenced by color sequence rather than depth maps, the qualities of both color and depth maps are firstly varied until the target 3D quality is achieved with minimal bit rate. Subsequently, the PSNR of both color and depth maps at the optimum point are maintained for the entire group of picture (GOP). The bit-allocation problem is solved by introducing a Lagrangian optimization cost function. According to experimental results, the proposed rate control technique is capable to adjust the bit rate allocated to the color and depth maps sequences adaptively in order to maximize 3D video quality which is measured by PSNR of the synthesized left and right views using reconstructed color and depth map sequences.