Android 通過AudioTrack播放CAF音頻

我們知道iPhone錄制的音頻都是caf格式,Android的Mediaplayer不支持這個格式的播放..那麼怎麼辦? 我們使用AudioTrack來播放!!代碼如下:

1. import android.app.Activity;
2. import android.os.Bundle;
3. import android.view.View;
4. import android.widget.Button;
5. import android.widget.TextView;
6. import android.media.MediaPlayer;
7. import android.media.AudioManager;
8. import android.media.AudioTrack;
9. import android.media.AudioFormat;
11. public class LRChannel extends Activity {
12. private Button lButton;
13. private Button rButton;
14. private TextView myTextView;
15. private MediaPlayer mMediaPlayer01 = null;
16. private AudioTrack aAudioTrack01 = null;
17. private String strFilePath = "/sdcard/test.caf";
18. private float midVol = 0;
20. /** Called when the activity is first created. */
21. @Override
22. public void onCreate(Bundle savedInstanceState) {
23. super.onCreate(savedInstanceState);
24. setContentView(R.layout.main);
26. lButton = (Button) findViewById(R.id.ButtonL);
27. rButton = (Button) findViewById(R.id.ButtonR);
28. myTextView = (TextView) findViewById(R.id.myTextView);
30. // left button response
31. lButton.setOnClickListener(new Button.OnClickListener()
32. {
33. @Override
34. public void onClick(View arg0)
35. {
36. playSound(strFilePath, 0);
38. }
39. });
41. // right button response
42. rButton.setOnClickListener(new Button.OnClickListener()
43. {
44. @Override
45. public void onClick(View arg0)
46. {
47. playSound(strFilePath, 1);
48. }
49. });
50. }
52. // iChannel = 0 means left channel test, iChannel = 1 means right channel test.
53. private void playSound(String strPath, int iChannel)
54. {
55. // If now is playing...
56. if ( aAudioTrack01 != null )
57. {
58. aAudioTrack01.release();
59. aAudioTrack01 = null;
60. }
61. // Get the AudioTrack minimum buffer size
62. int iMinBufSize = AudioTrack.getMinBufferSize(44100,
63. AudioFormat.CHANNEL_CONFIGURATION_STEREO,
64. AudioFormat.ENCODING_PCM_16BIT);
65. if ( iMinBufSize == AudioTrack.ERROR_BAD_VALUE || iMinBufSize == AudioTrack.ERROR )
66. {
67. return;
68. }
69. // Constructor a AudioTrack object
70. try
71. {
72. aAudioTrack01 = new AudioTrack(AudioManager.STREAM_MUSIC, 44100,
73. AudioFormat.CHANNEL_CONFIGURATION_STEREO,
74. AudioFormat.ENCODING_PCM_16BIT,
75. iMinBufSize,
76. AudioTrack.MODE_STREAM);
77. }
78. catch (IllegalArgumentException iae)
79. {
80. myTextView.setText("new AudioTrack Exceeption:" + iae.toString());
81. iae.printStackTrace();
82. }
83. // Write data to buffer
84. byte data[] = new byte[iMinBufSize];
85. aAudioTrack01.write(data, 0, data.length);
86. aAudioTrack01.write(data, 0, data.length);
87. float lValue = 0;
88. float rValue = 0;
90. if ( iChannel == 0 )
91. {
92. lValue = 1.0f;
93. rValue = 0.0f;
94. }
95. else if ( iChannel == 1 )
96. {
97. lValue = 0.0f;
98. rValue = 1.0f;
99. }
101. aAudioTrack01.play();
102. if ( aAudioTrack01.setStereoVolume(lValue, rValue) == AudioTrack.SUCCESS )
103. {
104. myTextView.setText("setStereoVolume successfully!");
105. }
106. aAudioTrack01.stop();
107. if ( aAudioTrack01.setStereoVolume(midVol, midVol) == AudioTrack.SUCCESS )
108. {
109. myTextView.setText("Restore setStereoVolume successfully!");
110. }
111. aAudioTrack01.release();
112. aAudioTrack01 = null;
113. }
115. @Override
116. protected void onDestroy() {
117. super.onDestroy();
118. // TODO Auto-generated method stub
119. if ( aAudioTrack01 != null ) {
120. aAudioTrack01.setStereoVolume(midVol, midVol);
121. aAudioTrack01.release();
122. aAudioTrack01 = null;
123. }
124. }
126. }

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