Research On The Optimization Of FFmpeg Encoder In Android-based Multimedia

With the trend of rapid development of mobile Internet nowadays, the demand for themobile terminals are no longer constrained to sending SMS and making phone calls. Moreand more people have regarded mobile phones as an entertainment tool in the daily life. Withthe popularity of smart phones as well as the improvement of its performance, multimediaapplications are just emerging in the endless stream. So it is said that the multimediaapplications will occupy a pivotal position in the field of mobile Internet in the future. As amobile Internet carrier, Android smartphone is currently one of the most popular smartphones, which has taken about78.1percent of the global market share and attracts a lot ofdevelopers to come around. However, the upper multimedia Java interface of Android systemis not expanding so rapidly as that of its market share. As many applications dealing withmultimedia streaming transmission and visualisation communication are based on theinfrastructure development of Andriod, it will not be possible to for developers to get startedon the work before they can get familiar with the underlying code of Andriod. And what’seven worse is that different developers will have different implementations. All thesephenomenons will it more difficult to develop new Andriod multimedia applications and thedevelopment cycle will be relatively longer than before.In order to achieve a common Android multimedia development solution and reduce thedevelopment cycle for developers, this paper trys to integrate the most popular audio andvideo codec library FFmpeg into the Android multimedia, and make use of the FFmpeginterface to achieve the purpose of the development of Android multimedia applications.Onthe other hand, this paper also proposes another solution to optimize the FFmpeg encoder,inorder to deal with the problem that FFmpeg can only be targeted at software coding, whichresults in low coding efficiency. What this paper does is to extract the hardware encoder withthe in-depth understanding of the mechanism of Andriod multimedia encoding and try tointegrate the encoder into FFmpeg as the format of a plug to achieve the efficient coding. In order to fully reflect the coding performance after the optimization with FFmpeg, thispaper trys to compare the results of video encoding before and after the optimization in threedifferent video resolution environment. The average coding efficiency, the average usage ofCPU and memory are recorded respectively at different resolutions. It showed that:It can be found from the perspective of the PSNR value that the video encoding quality isslightly better after optimization than before, but the video effect is exactly the same. Thedifference of the average CPU usage is not big due to the high load work of our environment.While in the resolution of144X176, the coding efficiency after optimization of FFmpeg isnearly eight times higher than that before optimisation of FFmpeg. And the higher theresolution is, the higher the mutiples of coding efficiency will be. When it comes to thematters of average usage of memory, it shows that the average usage after optimization isreduced by about2-fold than that before optimization. Therefore, we can get the conclusionthat the optimized FFmpeg encoder is even sutiable for Android platform comparing with nooptimized encoder.