Android音频开发之AudioRecord/Track

AudioRecord采集的是原始音频数据，一般的音频播放器无法直接播放PCM未编码的原始数据
/**

• Audio:采集原始（未编码）的数据（PCM）
• AudioTrack:播放未编码的PCM原始音频数据
• Audio主要是实现边录边播（AudioRecord+AudioTrack）以及对音频的实时处理（如会说话的汤姆猫、语音）
• 优点：语音的实时处理，可以用代码实现各种音频的封装
• 缺点：输出是PCM语音数据，如果保存成音频文件，是不能够被播放器播放的，所以必须先写代码实现数据编码以及压缩
  */

实现:

public class MyAudio {

    /**
     * 采集音频数据：
     * 1:配置参数，初始化音频缓冲区
     * 2:采集数据
     * 3:从缓冲区读取音频数据
     * 4:停止采集，释放资源
     */
    //采集缓冲区的大小
    private int receiveBufSize;
    //播放缓冲区的大小
    private int playBufSize;
    //采样率
    private static final int SAMPLE_RATE_HZ = 44100;
    //采集通道数
    private static final int CHANNEL_IN_COUNT = AudioFormat.CHANNEL_IN_MONO;
    //播放通道数
    private static final int CHANNEL_OUT_COUNT = AudioFormat.CHANNEL_OUT_MONO;
    //位数
    private static final int AUDIO_FORMAT = AudioFormat.ENCODING_PCM_16BIT;
    private AudioRecord audioRecord;
    private AudioTrack audioTrack;

    public MyAudio() {
        receiveBufSize = AudioRecord.getMinBufferSize(SAMPLE_RATE_HZ, CHANNEL_IN_COUNT, AUDIO_FORMAT);
        playBufSize = AudioTrack.getMinBufferSize(SAMPLE_RATE_HZ, CHANNEL_OUT_COUNT, AUDIO_FORMAT);


    }

    private boolean isRecording = false;

    public void startRecord() {
        isRecording = true;

        if (audioRecord == null)
            audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC,
                    SAMPLE_RATE_HZ, CHANNEL_IN_COUNT, AUDIO_FORMAT, receiveBufSize);
        if (audioTrack == null)
            audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, SAMPLE_RATE_HZ,
                    CHANNEL_OUT_COUNT, AUDIO_FORMAT, playBufSize, AudioTrack.MODE_STREAM);

        new RecodeThread().start();
    }

    public void stopRecord() {
        isRecording = false;
        //结束播放和采集
        audioTrack.stop();
        audioRecord.stop();
    }

    class RecodeThread extends Thread {

        @Override
        public void run() {

            byte[] buffer = new byte[receiveBufSize];
            audioRecord.startRecording();
            audioTrack.play();

            while (isRecording) {
                //从音频缓冲区读取音频数据
                audioRecord.read(buffer, 0, receiveBufSize);

                //播放声音
                audioTrack.write(buffer, 0, receiveBufSize);
            }

        }
    }
}