[Android] Media: Audio & Video

1. Docs
   
   • Audio and Video
     http://developer.android.com/guide/topics/media/index.html
     
   • Android Supported Media Formats
     http://developer.android.com/guide/appendix/media-formats.html
     
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2. Classes Summary
   
   • Audio
   • AudioManager
   • Sound Effects (音效)
     Sound effects are stored in memory and are usually no longer than a few seconds.
     
     
     • Ringtone & RingtoneManager
       Ringtone provides a quick method for playing a ringtone, notification, or other similar types of sounds.
     • ToneGenerator
       Provides methods to play DTMF tones (ITU-T Recommendation Q.23), call supervisory tones (3GPP TS 22.001, CEPT) and proprietary tones (3GPP TS 31.111)
     • SoundPool (Play sound effects)
       The SoundPool class manages and plays audio resources for applications.
       A SoundPool is a collection of samples that can be loaded into memory from a resource inside the APK or from a file in the file system. The SoundPool library uses the MediaPlayer service to decode the audio into a raw 16-bit PCM mono or stereo stream.
   • AudioTrack
     Manages and plays a single audio resource
     
     
   • AudioRecord
     Manages the audio resources record audio from the audio input hardware of the platform.
     
   • Video (& Audio)
     
     • MediaPlayer (Play stream music)
       Small sound effects fit into the limited heap memory an Android application gets from the operating system. Bigger audio files containing longer music pieces don’t. For this reason we need to stream the music to the audio hardware, which means that we only read-in a small chunk at a time, enough to decode it to raw PCM data and throw that at the audio chip. 
       
       Control playback of audio/video files and streams.
       
       
     • MediaRecorder
       Used to record audio and video.
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3. UI
   In general, SurfaceView is used to play media.
   
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