Transcript Slide 1
Media API Web Science APT 2007/2008 John Meilak Reuben Sant Jason Farrugia Introduction • Users demand rich multimedia capabilities Media API • Mobile hardware developed significantly • Mobile devices are not simply used for voice calls and text messaging Media Capabilities • Play, stream and record media resources • Audio • Video • Face Detection • Used to adjust camera settings on face Media API android.media Package • Classes • MediaPlayer • MediaRecorder • FaceDetector • AudioSystem • Interfaces • MediaPlayer.OnBufferingUpdateListener • MediaPlayer.OnCompletionListener • MediaPlayer.OnErrorListener • MediaPlayer.OnPreparedListener Media API MediaPlayer Example • Local Resource MediaPlayer mp = MediaPlayer.create (context, R.raw.sound_1); Media API • Stream mp.setDataSource(path); • Video mp.setDisplay(mPreview.getHolder().getSurface()); • An android.View.Surface is needed to display the video in it. • mPreview is of type android.view.SurfaceView which is defined in the xml layout file. • Playback mp.prepare(); mp.start(); MediaRecorder Example MediaRecorder rec = new MediaRecorder(); Media API rec.setVideoSource(MediaRecorder.VideoSource.CAMERA); rec.setAudioSource(MediaRecorder.AudioSource.MIC); rec.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP); rec.setVideoSize(400, 300); rec.setVideoFrameRate(24); rec.setVideoEncoder(MediaRecorder.VideoEncoder.H263); rec.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB); rec.setOutputFile(path); rec.prepare(); rec.start(); Supported Media Codecs • Audio Media API – MP3 compression scheme used to transfer audio files via internet and store in portable media players – AAC advanced audio coding, similar to mp3, used by iTunes – Ogg Vorbis a free and open source audio codec – MIDI used to describe a piece of music in enough detail to be able to reproduce it accurately – iMelody ringtone format – XMF extensible music format, used to keep file sizes as small as possible. used for polyphonic ringtones – RTTL/RTX ringtones format Supported Media Codecs • Video Media API – MPEG-4 compression algorithm for graphics, audio and video – H.264 simple standard providing good video quality at lower bit rates – 3GP simplified version of mpeg used to accommodate limited bandwidth of mobile phones References • http://code.google.com/android Media API • http://www.helloandroid.com • http://davanum.wordpress.com/2007/12/29/android -videomusic-player-sample-from-local-disk-aswell-as-remote-urls/ Media API