Android AudioRecord用于记录呼叫的设置

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

public class AudioRecordHelper {
    private static final int SAMPLE_RATE = 44100;
    private static final int CHANNEL_CONFIG = AudioFormat.CHANNEL_IN_DEFAULT;
    private static final int AUDIO_FORMAT = AudioFormat.ENCODING_PCM_16BIT;
    private static final int BUFFER_SIZE = AudioRecord.getMinBufferSize(SAMPLE_RATE, CHANNEL_CONFIG, AUDIO_FORMAT);

    private AudioRecord audioRecord;

    public void startRecording() {
        audioRecord = new AudioRecord.Builder()
                .setAudioSource(MediaRecorder.AudioSource.DEFAULT)
                .setAudioFormat(new AudioFormat.Builder()
                        .setEncoding(AUDIO_FORMAT)
                        .setSampleRate(SAMPLE_RATE)
                        .setChannelMask(CHANNEL_CONFIG)
                        .build())
                .setBufferSizeInBytes(BUFFER_SIZE)
                .build();
        audioRecord.startRecording();
    }

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

    public byte[] readData() {
        byte[] data = new byte[BUFFER_SIZE];
        int read = audioRecord.read(data, 0, BUFFER_SIZE);
        return data;
    }
}