Android MediaRecorder

MediaRecorder recorder;
Camera camera;
SurfaceView preview;
SurfaceHolder holder;
boolean isRecording = false;
String TAG = "Evolution Camera";
int frameRate = 30;

public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
    setContentView(R.layout.camera_view);

    preview = (SurfaceView) findViewById(R.id.camera_preview);

 // Add a listener to the Capture button
    ImageButton captureButton = (ImageButton) findViewById(R.id.btn_capture);
    captureButton.setOnClickListener(
        new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                record();
            }
        }
    );
}
private boolean prepareVideoRecorder(){

    camera = getCameraInstance();

    recorder = new MediaRecorder();

    // Step 1: Unlock and set camera to MediaRecorder
    camera.unlock();
    recorder.setCamera(camera);

    // Step 2: Set sources
    recorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
    recorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);

    // Step 3: Set a CamcorderProfile (requires API Level 8 or higher)
    recorder.setProfile(CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH));

    recorder.setVideoFrameRate(frameRate);

    // Step 4: Set output file
    recorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO).toString());

    // Step 5: Set the preview output
    recorder.setPreviewDisplay(preview .getHolder().getSurface());

    // Step 6: Prepare configured MediaRecorder
    try {
        recorder.prepare();
    } catch (IllegalStateException e) {
        Log.d(TAG, "IllegalStateException preparing MediaRecorder: " + e.getMessage());
        releaseMediaRecorder();
        return false;
    } catch (IOException e) {
        Log.d(TAG, "IOException preparing MediaRecorder: " + e.getMessage());
        releaseMediaRecorder();
        return false;
    }
    return true;
}

void record()
{

    if (isRecording) {
        // stop recording and release camera
        recorder.stop();  // stop the recording
        releaseMediaRecorder(); // release the MediaRecorder object
        camera.lock();         // take camera access back from MediaRecorder

        // inform the user that recording has stopped
        //setCaptureButtonText("Capture");
        isRecording = false;
    } else {
        // initialize video camera
        if (prepareVideoRecorder()) {
            // Camera is available and unlocked, MediaRecorder is prepared,
            // now you can start recording
            recorder.start();
            setParameters();

            // inform the user that recording has started
            //setCaptureButtonText("Stop");
            isRecording = true;
        } else {
            // prepare didn't work, release the camera
            releaseMediaRecorder();
            // inform user
        }
    }
}

void setParameters()
{
// set Camera parameters
   Camera.Parameters params = camera.getParameters();

   if (params.getMaxNumMeteringAreas() > 0){ // check that metering areas are supported
       List<Camera.Area> meteringAreas = new ArrayList<Camera.Area>();

       Rect areaRect1 = new Rect(-100, -100, 100, 100);    // specify an area in center of image
       meteringAreas.add(new Camera.Area(areaRect1, 600)); // set weight to 60%
       Rect areaRect2 = new Rect(800, -1000, 1000, -800);  // specify an area in upper right of image
       meteringAreas.add(new Camera.Area(areaRect2, 400)); // set weight to 40%
       params.setMeteringAreas(meteringAreas);

   }
   params.setFocusMode(Camera.Parameters.FOCUS_MODE_INFINITY);

   camera.setParameters(params);
}

    @Override
    protected void onPause() {
        super.onPause();
        if (isRecording) {
            recorder.stop();  // stop the recording
            releaseMediaRecorder(); // release the MediaRecorder object
            camera.lock();
            isRecording = false;
        }
        else {

            releaseMediaRecorder();
        }
        releaseCamera();
    }

    private void releaseMediaRecorder(){
        if (recorder != null) {
            recorder.reset();   // clear recorder configuration
            recorder.release(); // release the recorder object
            recorder = null;
            camera.lock();           // lock camera for later use
        }
    }

    private void releaseCamera(){
        if (camera != null){
            camera.release();        // release the camera for other applications
            camera = null;
        }
    }

/** Create a file Uri for saving an image or video */
private static Uri getOutputMediaFileUri(int type){
      return Uri.fromFile(getOutputMediaFile(type));
}

/** Create a File for saving an image or video */
private static File getOutputMediaFile(int type){
    // To be safe, you should check that the SDCard is mounted
    // using Environment.getExternalStorageState() before doing this.

    File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
              Environment.DIRECTORY_DCIM), "Evolution");
    // This location works best if you want the created images to be shared
    // between applications and persist after your app has been uninstalled.

    // Create the storage directory if it does not exist
    if (! mediaStorageDir.exists()){
        if (! mediaStorageDir.mkdirs()){
            Log.d("MyCameraApp", "failed to create directory");
            return null;
        }
    }

    // Create a media file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    File mediaFile;
    if (type == MEDIA_TYPE_IMAGE){
        mediaFile = new File(mediaStorageDir.getPath() + File.separator +
        "IMG_"+ timeStamp + ".jpg");

    } else if(type == MEDIA_TYPE_VIDEO) {
        mediaFile = new File(mediaStorageDir.getPath() + File.separator +
        "VID_"+ timeStamp + ".mp4");
        Log.d("MyCameraApp", "File created "+ mediaStorageDir.getPath().toString());
    } else {
        return null;
    }

    return mediaFile;
}

public static Camera getCameraInstance(){
    Camera c = null;
    try {
        c = Camera.open(); // attempt to get a Camera instance
    }
    catch (Exception e){
        // Camera is not available (in use or does not exist)
    }
    return c; // returns null if camera is unavailable
}

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    // TODO Auto-generated method stub

}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    // TODO Auto-generated method stub

}
@Override
public void surfaceCreated(SurfaceHolder holder) {
    // TODO Auto-generated method stub

}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
    // TODO Auto-generated method stub
    if (isRecording) {
        recorder.stop();
        isRecording = false;
    }
    recorder.release();

}

Android MediaRecorder