我有一个蓝牙耳机(它可以播放立体声音乐)连接到我的Android手机(Android 4.4.3) . 现在我希望我的代码能够以高采样率(44100)播放立体声音乐并从该耳机录制音频 . 我按照以下帖子中的解决方案 .
How to record sound using bluetooth headset
Capture Audio through Bluetooth Headset paired with Android Device
我的基本代码看起来像这样 .
权限:
android.permission.WRITE_EXTERNAL_STORAGE
android.permission.RECORD_AUDIO
android.permission.MODIFY_AUDIO_SETTINGS
android.permission.BROADCAST_STICKY
android.permission.BLUETOOTH
打开蓝牙Sco的代码:
m_amAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
public void turnOnBluetooth() {
final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
int state = intent.getIntExtra(AudioManager.EXTRA_SCO_AUDIO_STATE, -1);
if (AudioManager.SCO_AUDIO_STATE_CONNECTED == state) {
System.err.println("bluetooth connected");
unregisterReceiver(this);
} else if (AudioManager.SCO_AUDIO_STATE_DISCONNECTED == state) {
System.err.println("bluetooth disconnected");
}
}
};
registerReceiver(broadcastReceiver, new IntentFilter(
AudioManager.ACTION_SCO_AUDIO_STATE_UPDATED));
try {
if (m_amAudioManager.isBluetoothScoAvailableOffCall()) {
if (m_amAudioManager.isBluetoothScoOn()) {
m_amAudioManager.stopBluetoothSco();
m_amAudioManager.startBluetoothSco();
System.err.println("Bluetooth SCO On!");
} else {
System.err.println("Bluetooth Sco Off!");
m_amAudioManager.startBluetoothSco();
}
} else {
System.err.println("Bluetooth SCO not available");
}
} catch (Exception e) {
System.err.println("sco elsepart startBluetoothSCO " + e);
unregisterReceiver(broadcastReceiver);
}
}
播放立体声音乐的代码:
public void playMusic(){
this.mediaPlayer = new MediaPlayer();
this.mediaPlayer
.setOnCompletionListener(new OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
mp.release();
}
});
this.mediaPlayer.setDataSource(Environment.getExternalStorageDirectory().
getAbsolutePath()+ "/"+ folderName + "/stereo.wav");
// change type to STREAM_VOICE_CALL can partly solve the problem
// but reduces the quality of the music, which is critical in my case
this.mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
this.mediaPlayer.prepare();
this.mediaPlayer.start();
}
录制音频的代码:
public void recordAudio() {
AudioRecorder recorder = new AudioRecord(
audioSource, // MediaRecorder.AudioSource.MIC
RECORDER_SAMPLERATE, // 44100
RECORDER_CHANNELS, // AudioFormat.CHANNEL_IN_MONO
RECORDER_AUDIO_ENCODING, // AudioFormat.ENCODING_PCM_16BIT
bufferSize // obtained by AudioRecord.getMinBufferSize()
);
int i = recorder.getState();
if (i == 1)
recorder.startRecording();
// then read bytes from the recorder
}
这是怎么回事 .
案例1:如果我调用以下序列
turnOnBluetooth();
playMusic();
recordAudio();
音乐通过手机的扬声器而不是蓝牙耳机播放 . 录音机可以录制来自蓝牙耳机麦克风的声音,但采样率非常低(8kHz) .
情况2:如果我不调用turnOnBluetooth(),即执行以下序列
playMusic();
recordAudio();
音乐现在通过蓝牙耳机播放,但录音机仅记录手机内置麦克风的音频 .
我还试图改变AudioManager的模式
m_amAudioManager.setMode(AudioManager.MODE_IN_COMMUNICATION);
并设置音频路由
m_amAudioManager.setSpeakerphoneOn(false);
m_amAudioManager.setBluetoothScoOn(true);
结果与案例1相同 . 如果我设置
m_amAudioManager.setBluetoothScoOn(false);
它重复案例2 .
我已经为此工作了几天,上面的行为让我很困惑 . 我在音频设置中遗漏了什么吗?或者我需要使用蓝牙耳机的设置进行更复杂的控制?感谢您阅读本文,欢迎任何建议 . 谢谢!