With the rapid development of mobile Internet and mobile terminal equipment, mobile audio and video is applied more and more widely, the application software should process audio and video files efficiently to meet the needs of the public. For the purpose of improving the operational efficiency, this paper analysis and research multimedia processing, design and implement a lightweight audio and video engine, use the modular method, accomplished receive the media file, recognize the file format, separate containers into the audio and video streams and decode to output, use HTTP protocol and H.265 video decoder, AAC audio decoder, the software size is reduced to be smaller, then complete the Android platform interactive JNI, use the MediaPlayer of Android in the application to implement the audio and video play.