使用AudioRecord录音

虽然不知道头文件是咋回事,但是还是得到了一个MP3文件,音质也很清晰.AudioRecord是先把录制的声音保存为字节流文件,可以边保存边读取,头文件是把保存的字节流文件解析为音频格式.

public class MainActivity extends AppCompatActivity  {
    // 音频获取源
    private int audioSource = MediaRecorder.AudioSource.MIC;
    // 设置音频采样率，44100是目前的标准，但是某些设备仍然支持22050，16000，11025
    private static int sampleRateInHz = 44100;
    // 设置音频的录制的声道CHANNEL_IN_STEREO为双声道，CHANNEL_CONFIGURATION_MONO为单声道
    private static int channelConfig = AudioFormat.CHANNEL_IN_STEREO;
    // 音频数据格式:PCM 16位每个样本。保证设备支持。PCM 8位每个样本。不一定能得到设备支持。
    private static int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
    // 缓冲区字节大小
    private int bufferSizeInBytes = 0;
    private Button Start;
    private Button Stop;
    private AudioRecord audioRecord;
    private boolean isRecord = false;// 设置正在录制的状态
    //AudioName裸音频数据文件
    private static final String AudioName = "/sdcard/AAAData/love.raw";//不推荐这么写，可以用Enviroment.
    //NewAudioName可播放的音频文件
    private static final String NewAudioName = "/sdcard/AAAData/new.wav";

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().setFormat(PixelFormat.TRANSLUCENT);// 让界面横屏
        requestWindowFeature(Window.FEATURE_NO_TITLE);// 去掉界面标题
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        // 重新设置界面大小
        setContentView(R.layout.activity_main);
        init();
    }

    private void init() {
        Start = (Button) this.findViewById(R.id.button);
        Stop = (Button) this.findViewById(R.id.button2);
        Start.setOnClickListener(new TestAudioListener());
        Stop.setOnClickListener(new TestAudioListener());
        creatAudioRecord();
    }

    private void creatAudioRecord() {
        // 获得缓冲区字节大小
        bufferSizeInBytes = AudioRecord.getMinBufferSize(sampleRateInHz,
                channelConfig, audioFormat);
        // 创建AudioRecord对象
        audioRecord = new AudioRecord(audioSource, sampleRateInHz,
                channelConfig, audioFormat, bufferSizeInBytes);
    }

    class TestAudioListener implements View.OnClickListener {

        @Override
        public void onClick(View v) {
            if (v == Start) {
                startRecord();
            }
            if (v == Stop) {
                stopRecord();
            }

        }

    }

    private void startRecord() {
        audioRecord.startRecording();
        // 让录制状态为true
        isRecord = true;
        // 开启音频文件写入线程
        new Thread(new AudioRecordThread()).start();
    }

    private void stopRecord() {
        close();
    }

    private void close() {
        if (audioRecord != null) {
            System.out.println("stopRecord关闭");
            isRecord = false;//停止文件写入
            audioRecord.stop();
            audioRecord.release();//释放资源
            audioRecord = null;
        }
    }

    class AudioRecordThread implements Runnable {
        @Override
        public void run() {
            writeDateTOFile();//往文件中写入裸数据
            copyWaveFile(AudioName, NewAudioName);//给裸数据加上头文件
        }
    }

    /**
     * 这里将数据写入文件，但是并不能播放，因为AudioRecord获得的音频是原始的裸音频，
     * 如果需要播放就必须加入一些格式或者编码的头信息。但是这样的好处就是你可以对音频的裸数据进行处理，比如你要做一个爱说话的TOM
     * 猫在这里就进行音频的处理，然后重新封装 所以说这样得到的音频比较容易做一些音频的处理。
     */
    private void writeDateTOFile() {
        // new一个byte数组用来存一些字节数据，大小为缓冲区大小
        byte[] audiodata = new byte[bufferSizeInBytes];
        FileOutputStream fos = null;
        int readsize = 0;
        try {
            File file = new File(AudioName);
            if (file.exists()) {
                file.delete();
            }
            fos = new FileOutputStream(file);// 建立一个可存取字节的文件
        } catch (Exception e) {
            e.printStackTrace();
        }
        while (isRecord == true) {
            readsize = audioRecord.read(audiodata, 0, bufferSizeInBytes);
            if (AudioRecord.ERROR_INVALID_OPERATION != readsize) {
                try {
                    fos.write(audiodata);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        try {
            fos.close();// 关闭写入流
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 这里得到可播放的音频文件
    private void copyWaveFile(String inFilename, String outFilename) {
        FileInputStream in = null;
        FileOutputStream out = null;
        long totalAudioLen = 0;
        long totalDataLen = totalAudioLen + 36;
        long longSampleRate = sampleRateInHz;
        int channels = 2;
        long byteRate = 16 * sampleRateInHz * channels / 8;
        byte[] data = new byte[bufferSizeInBytes];
        try {
            in = new FileInputStream(inFilename);
            out = new FileOutputStream(outFilename);
            totalAudioLen = in.getChannel().size();
            totalDataLen = totalAudioLen + 36;
            WriteWaveFileHeader(out, totalAudioLen, totalDataLen,
                    longSampleRate, channels, byteRate);
            while (in.read(data) != -1) {
                out.write(data);
            }
            in.close();
            out.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 这里提供一个头信息。插入这些信息就可以得到可以播放的文件。
     * 为我为啥插入这44个字节，这个还真没深入研究，不过你随便打开一个wav
     * 音频的文件，可以发现前面的头文件可以说基本一样哦。每种格式的文件都有
     * 自己特有的头文件。
     */
    private void WriteWaveFileHeader(FileOutputStream out, long totalAudioLen,
                                     long totalDataLen, long longSampleRate, int channels, long byteRate)
            throws IOException {
        byte[] header = new byte[44];
        header[0] = 'R'; // RIFF/WAVE header
        header[1] = 'I';
        header[2] = 'F';
        header[3] = 'F';
        header[4] = (byte) (totalDataLen & 0xff);
        header[5] = (byte) ((totalDataLen >> 8) & 0xff);
        header[6] = (byte) ((totalDataLen >> 16) & 0xff);
        header[7] = (byte) ((totalDataLen >> 24) & 0xff);
        header[8] = 'W';
        header[9] = 'A';
        header[10] = 'V';
        header[11] = 'E';
        header[12] = 'f'; // 'fmt ' chunk
        header[13] = 'm';
        header[14] = 't';
        header[15] = ' ';
        header[16] = 16; // 4 bytes: size of 'fmt ' chunk
        header[17] = 0;
        header[18] = 0;
        header[19] = 0;
        header[20] = 1; // format = 1
        header[21] = 0;
        header[22] = (byte) channels;
        header[23] = 0;
        header[24] = (byte) (longSampleRate & 0xff);
        header[25] = (byte) ((longSampleRate >> 8) & 0xff);
        header[26] = (byte) ((longSampleRate >> 16) & 0xff);
        header[27] = (byte) ((longSampleRate >> 24) & 0xff);
        header[28] = (byte) (byteRate & 0xff);
        header[29] = (byte) ((byteRate >> 8) & 0xff);
        header[30] = (byte) ((byteRate >> 16) & 0xff);
        header[31] = (byte) ((byteRate >> 24) & 0xff);
        header[32] = (byte) (2 * 16 / 8); // block align
        header[33] = 0;
        header[34] = 16; // bits per sample
        header[35] = 0;
        header[36] = 'd';
        header[37] = 'a';
        header[38] = 't';
        header[39] = 'a';
        header[40] = (byte) (totalAudioLen & 0xff);
        header[41] = (byte) ((totalAudioLen >> 8) & 0xff);
        header[42] = (byte) ((totalAudioLen >> 16) & 0xff);
        header[43] = (byte) ((totalAudioLen >> 24) & 0xff);
        out.write(header, 0, 44);
    }

    @Override
    protected void onDestroy() {
        close();
        super.onDestroy();
    }
}

 <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

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