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In recent years, wireless mobile terminal PDA (personal digital assistant) with its small size , light weight , perfect function and many other features in the mobile office has played an important role in the field , as a new generation video coding standard , H.264 conditions in wireless local area with anti- BER ability and other characteristics , which for the wireless channel environment video transmission provides more technical assurance. Based on the H.264 coding standard features and the basic characteristics of PDA platform presents a wireless LAN environment video transmission system program, which uses H.264 as the video encoding method , PDA as a mobile terminal , RTP / UDP / IP as network transmission protocol, and on this basis, build a system demonstration platform . In order to strengthen the system error resilience , fault-tolerant approach to the original video has been improved in the transmission process to select a difference in protecting the principles and proposes a feedback based adaptive data loss split selection mode , namely RTP packetization video information data prior to roughly predict the next channel packet loss rate, packet loss rate according to the channel , we selected data from the main transmission mode , and on this basis to make further improvements to the data for further segmentation. Finally, the screen resolution of 720 * 480 screen , video playback speed of 30fps, the largest stream of 4Mbps, display frame rate 10 / s, under the conditions tested , the test results show that the method can be implemented in a wireless LAN environment real-time video transmission , high error at low broadband wireless channels , we get a clear picture .
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