| As the latest advance of video compression technology, the emerging H.264 Scalable Video Coding (H.264/SVC), an extension of H.264/AVC standard, has improved coding efficiency and provided a higher degree of scalability in temporal, spatial and SNR, when compared with previous scalable video coding schemes. The SVC design enables the creation of a video bit stream that is structured in layers, consisting of one base layer and one or more enhancement layers. Each enhancement layer either improves the resolution (spatially or temporally) or the quality of the video sequence. Meanwhile, the demand for high-quality mobile wireless communication services is increasing at an explosive rate primarily due to significant growth of multimedia data usage. As one of the most significant breakthroughs in wireless communications, Multiple Input Multiple Output (MIMO) technology, which puts multiple antennas at both the transmitter and the receiver to multiply throughput of a radio link, can provide higher level data throughput with extremely low latency. With a layer structure, SVC can gracefully make bitrate, format and power adaptation in lossy transmission environment to accommodate various video applications as well as diverse network requirements. As multi-layered H.264/SVC bitstreams are inherently suitable for parallel transmission over MIMO channels, it is undoubted that the natural integration of SVC with MIMO technique can significantly enhance the overall performance of wireless video applications.When compressing video streams for network transmission, over-rating the output of a video encoder may lead to network congestion and video data loss; while over-reduction of the output bit rate may result in unnecessary quality degradation and waste of available network bandwidth. Rate control (RC) must then be adopted to regulate the output bit rate of a video encoder to obtain optimum visual quality within the available network bandwidth and to maintain buffer fullness within a specified tolerance range. Therefore, RC plays a crucial role in video compression and communication.To integrate H.264/SVC with MIMO wireless system, this paper researchs the H264/SVC rate control algorithms and Joint H.264/SVC-MIMO rate control schema step by step, finally, we provide an efficient realtime wireless video compression and transmission system.The core content and novelties of this paper are as the follows:(1) This paper analyzes the principles and coding schemes of the SVC technologies, and existing Rate Control schemas.(2) This paper proposes a H.264/SVC initial QP calculation method for Intra frame, which provides more accurate initial QP estimation than existing methods.(3) This paper proposes an incremental H.264/SVC rate control algorithm. Comparing with the rate control algorithm using in H.264/SVC reference software JVSM, our rate control algorithm is not only able to handle basic layer rate control, but also all enhancement layers, while provide more accurate output bitrate and better quality.(4) Based on the incremental H.264/SVC rate control, this paper proposes an adaptive inter-layer rate control algorithm for Inter frames, which reduces the risk for abrupt change in video sequence and provides more accurate output.(5) To integrate the H.264/SVC rate control with MIMO wireless system, this paper proposes a extracting and re-assamble algorithm for H.264/SVC bitstream, which extracts different separate layer of H.264/SVC bitstream into sub-streams transferring on different MIMO channel, and re-assamble the sub-bitstreams into decodable SVC bitstream on the receiver side.(6) In the end, integrating the H.264/SVC rate control algorithm with MIMO wireless system, this paper proposes a Joint Source-Channel rate control algorithm, implements an efficient and stable wireless video compression and transmission system.
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