| Due to the explosive growth of the Internet and increasing demand for multimedia information on the web, streaming video over the Internet has received tremendous attention from academia and industry. Since transmission of real-time video over network typically has bandwidth, delay, continuity, and loss requirements, furthermore the channel is time-vary and heterogeneity, this thesis investigates several key areas of streaming video during source coding and channel communication. Specially, we focus on video compression, scalable encoding, application-layer transmission and controlling strategy, network protocols for real time streaming video.The main contributions and innovation points of the thesis are as follows:â… . In order to improve encoding efficiency, three algorithms are proposed as following: 1. the fast adaptive global motion estimation based on analyzing to statistical characteristic of motion vectors and calculating basic motion vectors of video frame is introduced. 2. The new region of interest video coding scheme is presented and is integrated with the novel bit allocation algorithm which is based on source content and interested extent. 3. The improved adaptive block size motion estimation based on rate-distortion optimization is proposed, and its parallel hardware architecture is designed, which aims to reduce processing complexity and delay.â…¡. The improved scalable encoding scheme is developed to make progressive streaming video more adaptive for long term bandwidth fluctuations and more flexible to transmit and control. It generates the base layer including some sub-base layers by coefficients reordering and VLC reshuffling, then the residues between the original coefficients and reconstructed coefficients of the base layer are encoded to the enhancement layer with bit plane coding technology. Furthermore, the multi description layered coding (MDLC) algorithm based on adaptive reference frame insertion is proposed, which combine both the advantages of multi description coding and scalable coding, and improve data robustness.â…¢. According to different error prone channel and data stream syntax, three advanced application-layer transmission and controlling strategies are proposed in this work. They are shown as following: 1. the proposed interactive unequal protection algorithm can investigate the channel feedback parameter and adjust sending rates and RCPC coding rates in real-time. 2. The proposed adaptive unequal packet loss protection strategy can determine current IP network status and estimate available bandwidth resources by calculating arithmetic equation, then adjust the number of sending layers and forward error correction schemes of those which are different important. 3. The efficient multipath transmission strategy is proposed for MDLC data stream over ad hoc network, and itcan choose sending contents adaptively according to the current statuses of differentpaths. â…£. The network protocol is presented to be used to transmit video data over packet basednetwork in real time. Its flow is discussed in detail on payload format, statisticalparameters of QoS status, wrong orders of received packets and adjustable buffercontrolling.All of the proposed algorithms in this thesis are simulated and examined, then compared with conventional schemes in order to prove their validities and advantages.
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