The Design And Implementation Of Portable Video Information Terminal Based On Embedded Linux

In recent years, multimedia technology is advancing by leaps and bounds along with the rapid development of computer technology and wireless communication. Associated with embedded digital video surveillance technology has entered into the various fields of human life and production.Most of the applications in multimedia technology involve wireless broadband video capture, monitor, transmission and Video Playback. This design has developed a wireless video portable terminal with multifunction which is combined with the popular WiFi and streaming media technology.The author make a second development on portable equipment based on Intel IPP Library and mysql database, which has a definite advantage over ffmpeg which is traditional software system core for video processing.At the beginning, thesis introduces hardware platform, software platform and cross-compiler environment for this design, and also some relatively platform porting for addition.Then, this thesis searches into analysis and implementation of transmission for video streaming media which is based on RTP/RTSP/RTCP protocol and also the realization of IP Multicast technology. The thesis elaborates on the design and implementation of MPEG4 video capture, coding, compression and code decoding process in details, also including its optimization based on the Intel IPP library to enhance the efficiency of MPEG4 decoder and the power of equipment. What's more, the design of a standard MP3 decoder is introduced. In addition, the realization of the Linux PCMCIA 802.11b Wireless Network Card Driver is one part of this paper.Secondly, the article focuses on the planning and realization of some functional modules such as e-government program background management, user management and personnel files management, all these are based on Mysql database management system on Linux.Based on various functional modules in conjunction with the detailed implementation steps, the thesis respectively discusses POSIX multithreading technology on Linux, Socket communication programming in details, Framebuffer writing on screen technology, video capture based on Linux V4L and some other advanced applications on Linux etc.At last, the article gives some testing data and experimental results in a specific laboratory environment. The summing up of the design, has analyzed the lack, the needed improvement and also the future prospects.Following the standard software development process, This design developed a portable multifunction wireless video terminal to meet the demand according to the present goal of realization, with the theoretical and practical value.