| Along with the development of digital compression technology and IP networks, the transmission of real-time multimedia especially real-time video&audio on the IP networks has been a research hotspot in the recent years. In real-time multimedia, the data of real-time video&audio, especially the real-time video are very big. The transmission of real-time video&audio puts forward a very high requirement to the bandwidth, delay, jitter of the networks. However, the development of digital compression technology let the quantity of the data of video&audio decreased greatly, this make the transmission on the present networks become possible. At the same time, the performance of IP networks is improved continuously. It is not only the increase of bandwidth, but also so many schemes put forward to support the quality of service of the networks. These make the real-time communications on the IP networks become possible.In this thesis, we bring forward a scheme to constuct embedded real-time video&audio transmission over IP networks, where the video&audio is MPEG-2 data flow. In the scheme, we design the hardware MPEG-2 encoding module and decoding module with the sigle MPEG-2 encoder chip and decoder chip. We use network processor which is ARM7TDMI core and uClinux which is open source to construct the embedded system. The 10/100M Ethernet interface is provided by the embedded system. In order to make the embedded system process the real-time MPEG-2 data flow, we extend the real-time data interface to it, including the hardware extension and the driver program. Based on above, a RTP/UDP data encapsulation scheme based on MPEG-2 TS (Transport Stream) and it's simplified process method are designed for the whole system. After concretely design, implementation, and. test on the 10/100M local area network, the scheme is proved to be effectively. At last, the paper analyses the impact of DP network transmission to the the video&audio of MPEG-2 decoder, and designs some measure methods for the system.
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