Based On Ffmpeg Vedio Format Conversion Design Under Embedded Linux Platform

In digital information age, embedded system has been rapid development because of itsembedded and special characteristics. In the process of multimedia technology development,video information is widely used owing to its advantages, such as strong intuitiveness, hugeinformation, facilitate comprehension and so on. As the market terminal equipments arechanged daily, more and more video formats appear to adapt to the different terminalequipments and application environment. Video format conversion became an importanttechnology to realize multimedia access. This paper realizes the video format conversion bytransplanting the FFmpeg open-source library on the embedded Linux platform.At first, the development of video format conversion software should build Linuxplatform. In this design, the main decoding chip is STi7105which has strong decoding abilityand can be compatible with the embedded Linux software development environment. In theprocess of platform building, the first step is compiling STLinux which should be transplantedto the targer after the success of compiling on the host. This design also presents a method toupdate file system by comparing with two versions of the file system, which can upgrade filesystem without erasing flash. Secondly, the theoretical knowledge of video format conversionis provided by analysising advanced coding technique H.264, AVI file format which is widelyused in the Windows system, and the struct of real-time stream TS. Finally, format conversioncan be realized by the FFmpeg open-source library which should be added external libx264toachieve H.264coding standard during configuer and cross compiling. The program in Clanguage is edited by calling the FFmpeg interface functions, so that, it can use socket toreceive UDP transmitted real time TS video stream and change it to the file format of AVI, ordirectly transform TS file to H.264encoded AVI file. Thereinto, the quality of encoded videocan be changed by the quantization step of encoder.The FFmpeg belongs to free open-source software for the convenience of the programeto be maintained and do the secondary development, as well as, the program in C language isflesible, and takes up small space, also it can be transplanted easily.