ho usato JavaCV biblioteca (che avvolge FFMPEG e OpenCV) per la modifica Frames. Cattura i fotogrammi su onPreviewFrame e registrali tramite il registratore FFMPEG.
Di seguito è riportato l'esempio RecordActivity.java.
public class RecordActivity extends Activity implements OnClickListener {
private final static String CLASS_LABEL = "RecordActivity";
private final static String LOG_TAG = CLASS_LABEL;
private PowerManager.WakeLock mWakeLock;
private String ffmpeg_link = "/mnt/sdcard/stream.flv";
long startTime = 0;
boolean recording = false;
private volatile FFmpegFrameRecorder recorder;
private boolean isPreviewOn = false;
private int sampleAudioRateInHz = 44100;
private int imageWidth = 320;
private int imageHeight = 240;
private int frameRate = 30;
/* audio data getting thread */
private AudioRecord audioRecord;
private AudioRecordRunnable audioRecordRunnable;
private Thread audioThread;
volatile boolean runAudioThread = true;
/* video data getting thread */
private Camera cameraDevice;
private CameraView cameraView;
private IplImage yuvIplimage = null;
/* layout setting */
private final int bg_screen_bx = 232;
private final int bg_screen_by = 128;
private final int bg_screen_width = 700;
private final int bg_screen_height = 500;
private final int bg_width = 1123;
private final int bg_height = 715;
private final int live_width = 640;
private final int live_height = 480;
private int screenWidth, screenHeight;
private Button btnRecorderControl;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
setContentView(R.layout.main);
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK, CLASS_LABEL);
mWakeLock.acquire();
initLayout();
initRecorder();
}
@Override
protected void onResume() {
super.onResume();
if (mWakeLock == null) {
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK, CLASS_LABEL);
mWakeLock.acquire();
}
}
@Override
protected void onPause() {
super.onPause();
if (mWakeLock != null) {
mWakeLock.release();
mWakeLock = null;
}
}
@Override
protected void onDestroy() {
super.onDestroy();
recording = false;
if (cameraView != null) {
cameraView.stopPreview();
}
if(cameraDevice != null) {
cameraDevice.stopPreview();
cameraDevice.release();
cameraDevice = null;
}
if (mWakeLock != null) {
mWakeLock.release();
mWakeLock = null;
}
}
private void initLayout() {
/* get size of screen */
Display display = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
screenWidth = display.getWidth();
screenHeight = display.getHeight();
RelativeLayout.LayoutParams layoutParam = null;
LayoutInflater myInflate = null;
myInflate = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
RelativeLayout topLayout = new RelativeLayout(this);
setContentView(topLayout);
LinearLayout preViewLayout = (LinearLayout) myInflate.inflate(R.layout.main, null);
layoutParam = new RelativeLayout.LayoutParams(screenWidth, screenHeight);
topLayout.addView(preViewLayout, layoutParam);
/* add control button: start and stop */
btnRecorderControl = (Button) findViewById(R.id.recorder_control);
btnRecorderControl.setText("Start");
btnRecorderControl.setOnClickListener(this);
/* add camera view */
int display_width_d = (int) (1.0 * bg_screen_width * screenWidth/bg_width);
int display_height_d = (int) (1.0 * bg_screen_height * screenHeight/bg_height);
int prev_rw, prev_rh;
if (1.0 * display_width_d/display_height_d > 1.0 * live_width/live_height) {
prev_rh = display_height_d;
prev_rw = (int) (1.0 * display_height_d * live_width/live_height);
} else {
prev_rw = display_width_d;
prev_rh = (int) (1.0 * display_width_d * live_height/live_width);
}
layoutParam = new RelativeLayout.LayoutParams(prev_rw, prev_rh);
layoutParam.topMargin = (int) (1.0 * bg_screen_by * screenHeight/bg_height);
layoutParam.leftMargin = (int) (1.0 * bg_screen_bx * screenWidth/bg_width);
cameraDevice = Camera.open();
Log.i(LOG_TAG, "cameara open");
cameraView = new CameraView(this, cameraDevice);
topLayout.addView(cameraView, layoutParam);
Log.i(LOG_TAG, "cameara preview start: OK");
}
//---------------------------------------
// initialize ffmpeg_recorder
//---------------------------------------
private void initRecorder() {
Log.w(LOG_TAG,"init recorder");
if (yuvIplimage == null) {
yuvIplimage = IplImage.create(imageWidth, imageHeight, IPL_DEPTH_8U, 2);
Log.i(LOG_TAG, "create yuvIplimage");
}
Log.i(LOG_TAG, "ffmpeg_url: " + ffmpeg_link);
recorder = new FFmpegFrameRecorder(ffmpeg_link, imageWidth, imageHeight, 1);
recorder.setFormat("flv");
recorder.setSampleRate(sampleAudioRateInHz);
// Set in the surface changed method
recorder.setFrameRate(frameRate);
Log.i(LOG_TAG, "recorder initialize success");
audioRecordRunnable = new AudioRecordRunnable();
audioThread = new Thread(audioRecordRunnable);
runAudioThread = true;
}
public void startRecording() {
try {
recorder.start();
startTime = System.currentTimeMillis();
recording = true;
audioThread.start();
} catch (FFmpegFrameRecorder.Exception e) {
e.printStackTrace();
}
}
public void stopRecording() {
runAudioThread = false;
try {
audioThread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
audioRecordRunnable = null;
audioThread = null;
if (recorder != null && recording) {
recording = false;
Log.v(LOG_TAG,"Finishing recording, calling stop and release on recorder");
try {
recorder.stop();
recorder.release();
} catch (FFmpegFrameRecorder.Exception e) {
e.printStackTrace();
}
recorder = null;
}
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
if (recording) {
stopRecording();
}
finish();
return true;
}
return super.onKeyDown(keyCode, event);
}
//---------------------------------------------
// audio thread, gets and encodes audio data
//---------------------------------------------
class AudioRecordRunnable implements Runnable {
@Override
public void run() {
android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
// Audio
int bufferSize;
short[] audioData;
int bufferReadResult;
bufferSize = AudioRecord.getMinBufferSize(sampleAudioRateInHz,
AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT);
audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, sampleAudioRateInHz,
AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, bufferSize);
audioData = new short[bufferSize];
Log.d(LOG_TAG, "audioRecord.startRecording()");
audioRecord.startRecording();
/* ffmpeg_audio encoding loop */
while (runAudioThread) {
//Log.v(LOG_TAG,"recording? " + recording);
bufferReadResult = audioRecord.read(audioData, 0, audioData.length);
if (bufferReadResult > 0) {
Log.v(LOG_TAG,"bufferReadResult: " + bufferReadResult);
// If "recording" isn't true when start this thread, it never get's set according to this if statement...!!!
// Why? Good question...
if (recording) {
try {
recorder.record(ShortBuffer.wrap(audioData, 0, bufferReadResult));
//Log.v(LOG_TAG,"recording " + 1024*i + " to " + 1024*i+1024);
} catch (FFmpegFrameRecorder.Exception e) {
Log.v(LOG_TAG,e.getMessage());
e.printStackTrace();
}
}
}
}
Log.v(LOG_TAG,"AudioThread Finished, release audioRecord");
/* encoding finish, release recorder */
if (audioRecord != null) {
audioRecord.stop();
audioRecord.release();
audioRecord = null;
Log.v(LOG_TAG,"audioRecord released");
}
}
}
//---------------------------------------------
// camera thread, gets and encodes video data
//---------------------------------------------
class CameraView extends SurfaceView implements SurfaceHolder.Callback, PreviewCallback {
private SurfaceHolder mHolder;
private Camera mCamera;
public CameraView(Context context, Camera camera) {
super(context);
Log.w("camera","camera view");
mCamera = camera;
mHolder = getHolder();
mHolder.addCallback(CameraView.this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mCamera.setPreviewCallback(CameraView.this);
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
stopPreview();
mCamera.setPreviewDisplay(holder);
} catch (IOException exception) {
mCamera.release();
mCamera = null;
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Log.v(LOG_TAG,"Setting imageWidth: " + imageWidth + " imageHeight: " + imageHeight + " frameRate: " + frameRate);
Camera.Parameters camParams = mCamera.getParameters();
camParams.setPreviewSize(imageWidth, imageHeight);
Log.v(LOG_TAG,"Preview Framerate: " + camParams.getPreviewFrameRate());
camParams.setPreviewFrameRate(frameRate);
mCamera.setParameters(camParams);
startPreview();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
try {
mHolder.addCallback(null);
mCamera.setPreviewCallback(null);
} catch (RuntimeException e) {
// The camera has probably just been released, ignore.
}
}
public void startPreview() {
if (!isPreviewOn && mCamera != null) {
isPreviewOn = true;
mCamera.startPreview();
}
}
public void stopPreview() {
if (isPreviewOn && mCamera != null) {
isPreviewOn = false;
mCamera.stopPreview();
}
}
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
/* get video data */
if (yuvIplimage != null && recording) {
yuvIplimage.getByteBuffer().put(data);
Log.v(LOG_TAG,"Writing Frame");
try {
long t = 1000 * (System.currentTimeMillis() - startTime);
if (t > recorder.getTimestamp()) {
recorder.setTimestamp(t);
}
recorder.record(yuvIplimage);
} catch (FFmpegFrameRecorder.Exception e) {
Log.v(LOG_TAG,e.getMessage());
e.printStackTrace();
}
}
}
}
@Override
public void onClick(View v) {
if (!recording) {
startRecording();
Log.w(LOG_TAG, "Start Button Pushed");
btnRecorderControl.setText("Stop");
} else {
// This will trigger the audio recording loop to stop and then set isRecorderStart = false;
stopRecording();
Log.w(LOG_TAG, "Stop Button Pushed");
btnRecorderControl.setText("Start");
}
}
}
