Media Player Based On Android And Opengl

The birth of the Android Operating System, which is open and free，has brought ahuge change to the area of mobile network application, such as3G network. Since in2007,Google brought Android to the world，thousands of android applications，gamesand network services had been created fantastically，bringing the users of smart phonesmany kinds of conveniences and wonderful experience.The applications ofmulti-media，such as camera，recorder and media player have beautiful user interfaces，common functions of picking up of media resource or playback and even some otherhigh level application function，like searching files on net or local system and editingmedia files.The main goal of this theis is analyzing multimedia framework OpenCore andStagefright of Android and the encoding algorithm of audio/video files(using FFmpeg),which surpports the audio/vedio files and RTSP/RTP streams files are sampled andplayed back in high quality. Meanwhile, the author creates a multimedia player thatincludes the audio/video player and picture viewer. Based on OpenGL, the authorcreates three dimensions audio/video file play list view and picture gallery preview list.The media player includes the functions of media files playing control and some simpleediting operations of media files. Audio/video player includes mainy functions, suchas, playing, stopping, pausing, back and forward，circle play mode, separating ofaudio and video file within a video file，cutting a picture from a video，cutting，copyingand pasting of audio/video files, editing captions of video files and synchronization ofaudio song words, etc.The creative work of this thesis includes are listed as bellow.(1) Using OpenGL to create Three Dimensions audio/video files playing list views.(2) Using FFmpeg decoder to decode audio/video files, adding the functions ofaudio/video seperation, editing, sreenshot and captions editing.(3) Proposing an algrorithom for the synchronization of audio/video files. The principleof this algrorithom is that marking the audio/video files with Time Stamp when encoded,collecting the Time Stamp after decoding the video/audio in buffers, and inputting the samples into the synchronism controlling system. We choose a Reference Clock for thesynchronism controlling in the system, which is used to compare the Time Stamp of theinput audio/video samples. If the audio sample is input first, then output it as apriority.If the video arrives first, make it wait. If the video sample arrives late and theaudio file is output then reject the video sample. After outputting the audio/videosamples, the system use Quality Control System to feedback the synchronisminformation to the input buffer, notifying it to control the input.