java – Android AudioRecord不会初始化

我正在尝试实现一个监听麦克风输入(特别是呼吸)的应用程序,并根据它提供数据.我正在使用 Android类AudioRecord,在尝试实例化AudioRecord时,我得到了三个错误.

AudioRecord: audioflinger Could not create record track,status: -1
AudioRecord-JNI: Error creating AudioRecord instance: initialization check Failed with status -1.
android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.

我找到了这个优秀的主题：AudioRecord object not initializing

我从已接受的答案中借用了代码,尝试所有采样率,音频格式和通道配置以尝试解决问题,但它没有帮助,我得到了所有设置的上述错误.我还根据线程中的一个答案在几个地方添加了对AudioRecord.release()的调用,但它没有任何区别.

这是我的代码：

import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;
import android.util.Log;

public class SoundMeter {

private AudioRecord ar = null;
private int minSize;
private static int[] mSampleRates = new int[] { 8000,11025,22050,32000,44100 };

public boolean start() {
    ar = findAudioRecord();
    if(ar != null){
        ar.startRecording();
        return true;
    }
    else{
        Log.e("SoundMeter","ERROR,Could not create audio recorder");
        return false;
    }
}

public void stop() {
    if (ar != null) {
        ar.stop();
        ar.release();
    }
}

public double getAmplitude() {
    short[] buffer = new short[minSize];
    ar.read(buffer,minSize);
    int max = 0;
    for (short s : buffer)
    {
        if (Math.abs(s) > max)
        {
            max = Math.abs(s);
        }
    }
    return max;
}

public AudioRecord findAudioRecord() {
    for (int rate : mSampleRates) {
        for (short audioFormat : new short[] { AudioFormat.ENCODING_PCM_8BIT,AudioFormat.ENCODING_PCM_16BIT,AudioFormat.ENCODING_PCM_FLOAT }) {
            for (short channelConfig : new short[] { AudioFormat.CHANNEL_IN_MONO,AudioFormat.CHANNEL_IN_STEREO }) {
                try {
                    Log.d("SoundMeter","Attempting rate " + rate + "Hz,bits: " + audioFormat + ",channel: " + channelConfig);
                    int bufferSize = AudioRecord.getMinBufferSize(rate,channelConfig,audioFormat);

                    if (bufferSize != AudioRecord.ERROR_BAD_VALUE) {
                        // check if we can instantiate and have a success
                        Log.d("SoundMeter","Found a supported bufferSize,attempting to instantiate");
                        AudioRecord recorder = new AudioRecord(MediaRecorder.AudioSource.DEFAULT,rate,audioFormat,bufferSize);

                        if (recorder.getState() == AudioRecord.STATE_INITIALIZED){
                            minSize = bufferSize;
                            return recorder;
                        }
                        else
                            recorder.release();
                    }
                } catch (Exception e) {
                    Log.e("SoundMeter",rate + " Exception,keep trying.",e);
                }
            }
        }
    }
    return null;
}

}

我也加了

<uses-permission android:name="android.permission.RECORD_AUdio"/>

根据上面提到的线程中的其他答案之一,标记到我的清单文件,作为清单标记的子项和应用程序标记的兄弟.我在添加此标记后重建了该项目.

这些是我在搜索问题时找到的解决方案,但不幸的是,它们似乎并没有为我做到这一点.
我正在调试我的Nexus 5手机(不是模拟器).调用AudioRecord的构造函数时会出现这些错误.我已经多次重启我的手机试图释放麦克风,但无济于事.该项目基于Android 4.4,我的手机目前运行的是Android 6.0.1.

非常感谢我可以尝试的其他一些提示,我可能错过了什么.谢谢！

private void requestRecordAudioPermission() {
    //check API version,do nothing if API version < 23!
    int currentapiVersion = android.os.Build.VERSION.SDK_INT;
    if (currentapiVersion > android.os.Build.VERSION_CODES.LOLLIPOP){

        if (ContextCompat.checkSelfPermission(this,Manifest.permission.RECORD_AUdio) != PackageManager.PERMISSION_GRANTED) {

            // Should we show an explanation?
            if (ActivityCompat.shouldShowRequestPermissionRationale(this,Manifest.permission.RECORD_AUdio)) {

                // Show an expanation to the user *asynchronously* -- don't block
                // this thread waiting for the user's response! After the user
                // sees the explanation,try again to request the permission.

            } else {

                // No explanation needed,we can request the permission.

                ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.RECORD_AUdio},1);
            }
        }
    }
}

@Override
public void onRequestPermissionsResult(int requestCode,String permissions[],int[] grantResults) {
    switch (requestCode) {
        case 1: {
            // If request is cancelled,the result arrays are empty.
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                // permission was granted,yay! Do the
                // contacts-related task you need to do.
                Log.d("Activity","Granted!");

            } else {

                // permission denied,boo! disable the
                // functionality that depends on this permission.
                Log.d("Activity","Denied!");
                finish();
            }
            return;
        }

        // other 'case' lines to check for other
        // permissions this app might request
    }
}