Design And Implementation Of Mobile Streaming Media Player Based On Handheld Devices

With the 3G and Mobile Internet era's coming, Mobile Streaming Media is widely accepted by people. In support of streaming media technology, mobile phone users can enjoy streaming media data anytime, anywhere. It is based on the above background, the paper designs and implements the streaming media client based on smart phone platform, the ultimate goal is to make phone communicate with the media server, receive and play real-time streaming media data by 3G Wireless Networks. Around this core objective, this paper has carried out the following tasks:1)Introduce the application status and development trend of streaming media technology. Analyze the development background of smart phones. Determine to use Windows Mobile operating system as the research platform of this article by comparison of popular smart phone operating system. Describe an overview of Windows Mobile operating system, and the key technology of streaming media has been discussed.2)According to the constraints of smart devices, taking full account of the characteristics of wireless networks, the solution of mobile streaming media system is proposed as Client/Server architecture.We focus on client functional module division and implementation. Based on analysis of project requirements, the client is divided by five parts:User Interface module, session control module, data transfer module, data storage module and audio/video decoding playback module.3)User Interface module implements a simple user interface of player; session control module transplants and reconstructs a private session control protocol, makes the client communicate with the server; data transfer module proposes two data transfer mechanisms for two different models of video-on-demand and live-video; data storage module presents a highly efficient algorithm of memory buffer operation; audio/video decoding playback module transplants the third party open source libraries FFmpeg and SDL to the Windows Mobile platform, and realizes the audio/video decoding engine according to their multimedia framework.4)According to streaming media client's problems and deficiencies, we respectively optimize the packet loss retransmission strategy, audio and video synchronization algorithm, audio and video decoding code, and memory buffer control algorithm.Based on the above work, on the Windows Mobile 6.0 platform, in the China Mobile TD-SCDMA network environment, we test the client's functionality and performance. It successfully implements the basic functions of streaming media playing, with good fluency and user experience.