Is there a documentation explaining android Stagefright architecture?
Can I get some pointers on these subjects?
Answer
A good explanation of stagefright is provided at http://freepine.blogspot.com/2010/01/overview-of-stagefrighter-player.html.
There is a new playback engine implemented by Google comes with Android 2.0 (i.e, Stagefright), which seems to be quite simple and straightforward compared with the OpenCORE solution.
- MediaExtractor is responsible for retrieving track data and the corresponding meta data from the underlying file system or http stream;
- Leveraging OMX for decoding: there are two OMX plugins currently, adapting to PV's software codec and vendor's hardware implementation respectively. And there is a local implementation of software codecs which encapsulates PV's decoder APIs directly;
- AudioPlayer is responsible for rendering audio, it also provides the timebase for timing and A/V synchronization whenever audio track is present;
- Depending on which codec is picked, a local or remote render will be created for video rendering; and system clock is used as the timebase for video only playback;
- AwesomePlayer works as the engine to coordinate the above modules, and is finally connected into android media framework through the adapter of StagefrightPlayer.
