Android : recording audio using audiorecord class play as fast forwarded

Question

I am trying to record a audio & stores into a sdcard as well as send to server. When I am trying to play recorded voice its playing,but not as I have recorded. If I rec

Answer 1

I got the solution.. here is my code

public class Audio_Record extends Activity {
private static final int RECORDER_SAMPLERATE = 8000;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
private AudioRecord recorder = null;
private Thread recordingThread = null;
private boolean isRecording = false;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    setButtonHandlers();
    enableButtons(false);

    int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,
            RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);

    System.out.println("BUFFER SIZE VALUE IS " + bufferSize);

}

private void setButtonHandlers() {
    ((Button) findViewById(R.id.btnStart)).setOnClickListener(btnClick);
    ((Button) findViewById(R.id.btnStop)).setOnClickListener(btnClick);
}

private void enableButton(int id, boolean isEnable) {
    ((Button) findViewById(id)).setEnabled(isEnable);
}

private void enableButtons(boolean isRecording) {
    enableButton(R.id.btnStart, !isRecording);
    enableButton(R.id.btnStop, isRecording);
}

int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we
                                // use only 1024
int BytesPerElement = 2; // 2 bytes in 16bit format

private void startRecording() {

    recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
            RECORDER_SAMPLERATE, RECORDER_CHANNELS,
            RECORDER_AUDIO_ENCODING, BufferElements2Rec * BytesPerElement);

    recorder.startRecording();
    isRecording = true;

    recordingThread = new Thread(new Runnable() {

        public void run() {

            writeAudioDataToFile();

        }
    }, "AudioRecorder Thread");
    recordingThread.start();
}

private byte[] short2byte(short[] sData) {
    int shortArrsize = sData.length;
    byte[] bytes = new byte[shortArrsize * 2];

    for (int i = 0; i < shortArrsize; i++) {
        bytes[i * 2] = (byte) (sData[i] & 0x00FF);
        bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
        sData[i] = 0;
    }
    return bytes;

}

private void writeAudioDataToFile() {
    // Write the output audio in byte

    String filePath = "/sdcard/voice8K16bitmono.pcm";
    short sData[] = new short[BufferElements2Rec];

    FileOutputStream os = null;
    try {
        os = new FileOutputStream(filePath);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }

    while (isRecording) {
        // gets the voice output from microphone to byte format

        recorder.read(sData, 0, BufferElements2Rec);
        System.out.println("Short wirting to file" + sData.toString());
        try {
            // // writes the data to file from buffer
            // // stores the voice buffer

            byte bData[] = short2byte(sData);

            os.write(bData, 0, BufferElements2Rec * BytesPerElement);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    try {
        os.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

private void stopRecording() {
    // stops the recording activity
    if (null != recorder) {
        isRecording = false;

        recorder.stop();
        recorder.release();

        recorder = null;
        recordingThread = null;
    }
}

private View.OnClickListener btnClick = new View.OnClickListener() {
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.btnStart: {
            enableButtons(true);
            startRecording();
            break;
        }
        case R.id.btnStop: {
            enableButtons(false);
            stopRecording();
            break;
        }
        }
    }
};

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {

    if (keyCode == KeyEvent.KEYCODE_BACK) {

        finish();
    }
    return super.onKeyDown(keyCode, event);
}
}

Answer 2

I had a lot of trouble implementing this for myself. I had done many of the things everyone said above. I implemented this as it's own class called Recorder (and rolled in all of the above 'fixes' as well as a few other tweaks). I hope my code can help someone else save the many hours I laboured over this:

public class Recorder {

    //Begin private fields for this class
    private AudioRecord recorder;

    private static final int RECORDER_BPP = 16;
    private static final String AUDIO_RECORDER_FILE_EXT_WAV = "AudioRecorder.wav";
    private static final String AUDIO_RECORDER_FOLDER = "AudioRecorder";
    private static final String AUDIO_RECORDER_TEMP_FILE = "record_temp.raw";
    private static final int RECORDER_SAMPLERATE = 8000;
    private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
    private static final int RECORDER_CHANNELS_INT = 1;

    private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;

    private int bufferSize = 200000;
    short[] buffer;
    private Thread recordingThread = null;
    private boolean isRecording = false;

    //Constructor
    Recorder(String uniquename)
    {
        //Initilize our recorder object
        /*recorder = new AudioRecord(
                MediaRecorder.AudioSource.MIC, 
                44100, 
                AudioFormat.CHANNEL_IN_MONO, 
                AudioFormat.ENCODING_PCM_16BIT,
                AudioRecord.getMinBufferSize(44100,AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT)
                );
                */

         int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,
                    RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);

            System.out.println("BUFFER SIZE VALUE IS " + bufferSize);

          int buffercount = 4088 / bufferSize;
            if (buffercount < 1)
                buffercount = 1;
        recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
                RECORDER_SAMPLERATE, RECORDER_CHANNELS,
                RECORDER_AUDIO_ENCODING, 44100);

        //recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        //recorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
        //recorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);


    }

    public void start() throws IllegalStateException, IOException
    {

            buffer = new short[4088];

            recorder.startRecording();

            isRecording = true;

            recordingThread = new Thread(new Runnable() 
            {
                @Override
                public void run() {
                    writeAudioDataToFile();
                }
            }, "AudioRecorder Thread");

            recordingThread.start();
    }

    public void stop()
    {
        System.out.println("Told to stop"); 
         stopRecording();
    }

    public boolean isRecording()
    {
        if(recorder.getRecordingState() == AudioRecord.RECORDSTATE_RECORDING)
            return true;
        else
            return false;
    }


    private void stopRecording() {
        // stops the recording activity

        if (null != recorder) {
            isRecording = false;

            recorder.stop();


            recorder.release();

                recorder = null;
                recordingThread = null;}
            // copy the recorded file to original copy & delete the recorded copy
            copyWaveFile(getTempFilename(), getFilename());
            deleteTempFile();
    } // stores the file into the SDCARD
        private String getFilename() {
            System.out.println("---3---");
            String filepath = Environment.getExternalStorageDirectory().getPath();
            File file = new File(filepath, AUDIO_RECORDER_FOLDER);

            if (!file.exists()) {
                file.mkdirs();
            }

            return (file.getAbsolutePath() + "/" + AUDIO_RECORDER_FILE_EXT_WAV);
        }


    private void deleteTempFile() {
        File file = new File(getTempFilename());

        file.delete();
    }


    private void copyWaveFile(String inFilename, String outFilename) {
    System.out.println("---8---");
    FileInputStream in = null;
    FileOutputStream out = null;
    long totalAudioLen = 0;
    long totalDataLen = totalAudioLen + 36;
    long longSampleRate = RECORDER_SAMPLERATE;
    int channels = RECORDER_CHANNELS_INT;
    long byteRate = RECORDER_BPP * RECORDER_SAMPLERATE * channels / 8;

    byte[] data = new byte[bufferSize];

    try {
        in = new FileInputStream(inFilename);
        out = new FileOutputStream(outFilename);
        totalAudioLen = in.getChannel().size();
        totalDataLen = totalAudioLen + 36;

        Controller.doDoc("File size: " + totalDataLen, 4);

        WriteWaveFileHeader(out, totalAudioLen, totalDataLen,
                longSampleRate, channels, byteRate);
        byte[] bytes2 = new byte[buffer.length * 2];
        ByteBuffer.wrap(bytes2).order(ByteOrder.LITTLE_ENDIAN)
                .asShortBuffer().put(buffer);
        while (in.read(bytes2) != -1) {
            out.write(bytes2);
        }

        in.close();
        out.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

    // stores the file into the SDCARD
    private String getTempFilename() {
        // Creates the temp file to store buffer
        System.out.println("---4-1--");
        String filepath = Environment.getExternalStorageDirectory().getPath();
        System.out.println("---4-2--");
        File file = new File(filepath, AUDIO_RECORDER_FOLDER);
        System.out.println("---4-3--");

        if (!file.exists()) {
            file.mkdirs();
        }

        File tempFile = new File(filepath, AUDIO_RECORDER_TEMP_FILE);
        System.out.println("---4-4--");

        if (tempFile.exists())
            tempFile.delete();
        System.out.println("---4-5--");
        return (file.getAbsolutePath() + "/" + AUDIO_RECORDER_TEMP_FILE);
    }
    private void writeAudioDataToFile() {

        // Write the output audio in byte
        byte data[] = new byte[bufferSize];

        String filename = getTempFilename();
        //
        FileOutputStream os = null;
        //
        try {
            //
            os = new FileOutputStream(filename);
            //
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        int read = 0;


        // if (null != os) {
        while (isRecording) {
            // gets the voice output from microphone to byte format
            recorder.read(buffer, 0, buffer.length);            
            // read = recorder.read(data, 0, 6144);

            if (AudioRecord.ERROR_INVALID_OPERATION != read) {
                try {
                    // // writes the data to file from buffer
                    // // stores the voice buffer

                    // short[] shorts = new short[bytes.length/2];
                    // to turn bytes to shorts as either big endian or little
                    // endian.
                    // ByteBuffer.wrap(bytes).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer().get(shorts);

                    // to turn shorts back to bytes.
                    byte[] bytes2 = new byte[buffer.length * 2];
                    ByteBuffer.wrap(bytes2).order(ByteOrder.LITTLE_ENDIAN)
                            .asShortBuffer().put(buffer);

                    os.write(bytes2);
                 //  ServerInteractor.SendAudio(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        try {
            os.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private void WriteWaveFileHeader(FileOutputStream out, long totalAudioLen,
            long totalDataLen, long longSampleRate, int channels, long byteRate)
            throws IOException {
        System.out.println("---9---");
        byte[] header = new byte[4088];

        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) RECORDER_CHANNELS_INT;
        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) (RECORDER_CHANNELS_INT * RECORDER_BPP / 8); // block align
        header[33] = 0;
        header[34] = RECORDER_BPP; // 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, 4088);
    }
}

Answer 3

int channels = 1 instead of int channels = 2 for CHANNELS = AudioFormat.CHANNEL_IN_MONO!