Design And Implementation Of Mobile Streaming Media System Based On Wireless Network Environment

In recent years, due to the popularity of a variety of user terminals and wireless networks, content sharing service has become one of the most popular services. Content sharing services means that the same content will be shared at the same time or at different times by many terminal equipments.Streaming Media has become a very significant trend in the content sharing services. Shareing system based on the contents transfer multimedia content from the streaming server to clients through the network media,and clients decode them by the decoder after receiving streaming data. However, due to unstability and vulnerablity to interference of the wireless network, the client will be greatly affected and thus requires an adjustment mechanism to ensure good viewing experience of the client.Paper propose a self-adaptive adjustment program.According to the network feedback, such as bandwidth, packet loss rate.etc, the server dynamically adjusts the sending rate or the bit rate of the video stream in order to accommodate this network’s changes and to ensure the fluency of playback. Finally, streaming media system based on open source DSS (Darwin streaming server) is realized, including the streaming media server and the client.Streaming media server responds to the client’s request, transmit the media stream data, and adjust according to the network conditions. Server uses RTSP,RTP and RTCP. RTSP protocol mainly achieves the session interaction between the client and the streaming media server,allows the client to be able to remotely control a streaming media to meet the real-time interaction of playing, pausing and playing. RTP protocol is mainly responsible for real-time streaming data transmission.RTCP is a control protocol and provides flow control and congestion control together with RTP, primarily responsible for managing the transmission quality and providing reliable transport mechanism for data packets.The client is primarily responsible for receiving the stream data, feeding back network condition and decoding the data. The client uses JRTPLIB(an open source library) to receive data and feed back network status. JRTPLIB is RTP library based on C++, it realizes RTP and RTCP protocol. Ffmpeg is an open source library, achieving decoding and displaying stream data.It has a good portability and high-quality codec. Therefore, the client transplants FFMPEG to the Android system, decoding streaming media data.Finally, through experiments, the self-adaptive adjustment mechanism can well adapt to changes in network conditions and ensure that the client is able to receive smoothly stream data and decode them.