Rate Control And Transmission Based On HD Scalability Video Coding

Due to the obvious development and popularization of Internet, network has affected many human areas such as life, study, work and so on. According to intuitive and luxuriant feature of video, people has preferred video than the traditional newspaper and books. And beyond the simple demand of "visible" situation, high-definition video has become a major business video services. However, the heterogeneity of the network, fluctuations of network bandwidth, capabilities of display of different terminals (size of terminal display and method of video play) become the primary challenges for video encoding and transmission. Scalable video coding technology is proposed to solve these problems. The development of scalable video coding can meet different video services like video conference, mobile wireless video, video phone, video surveillance and real time transmission.In order to solve the video transmission over heterogeneous network, on the basis of research of coding technology of scalable video coding, two aspects of research was processed as follows:(1) SVC can address the application need of a more flexible format of coded video in heterogeneous and time-varying environments. Rate Control (RC) plays an important role in allocating SVC bits to adapt to the actual channel bandwidth and meanwhile achieve high-quality reconstructed images. In this paper, a macroblock level rate control algorithm based on layer level and MB level bit-rate allocation is proposed for SVC spatial and MGS scalability. At the same time, we bring in layer level buffer control. The coding process of each layer is controlled by a respective buffer controller and a train of RC parameters. Experimental results show that the proposed algorithm can achieve accurate bit-rate and maintain the maximum mismatch between actual bit-rate and target bit-rate. Compared with FixQpEncoder adopted in the Joint Scalable Video Model (JSVM), the proposed algorithm is able to obtain high PSNR, and don’t need multiple iterative, reduce the complexity and can meet the real-time demand.(2) Due to the obvious development of wireless network and video application, video encoding and transmission become the major problem for wireless transmission. To cope with this problem, we propose a video streaming distribution algorithm using H.264/SVC in this paper, which is based on Variance Coefficient Weighting (VCM) and Modified Grey Relational Analysis (MGRA). In this proposed algorithm, different channels parameters are considered comprehensively, therefore, the dynamic option of networks can be determined when SVC steaming is transmitted over the heterogeneous wireless network. Experimental results illustrate that the proposed algorithm can improve transmission efficiency and decoded quality of SVC video comparing with the algorithm of Bandwidth Optimal and Bit Error Optimal.