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  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • Installation en mode ferme

    4 février 2011, par

    Le mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
    C’est la méthode que nous utilisons sur cette même plateforme.
    L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
    Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...)

  • Automated installation script of MediaSPIP

    25 avril 2011, par

    To overcome the difficulties mainly due to the installation of server side software dependencies, an "all-in-one" installation script written in bash was created to facilitate this step on a server with a compatible Linux distribution.
    You must have access to your server via SSH and a root account to use it, which will install the dependencies. Contact your provider if you do not have that.
    The documentation of the use of this installation script is available here.
    The code of this (...)

Sur d’autres sites (6938)

  • libavcodec get video duration and framerate

    17 septembre 2013, par Tishu

    I have a video encoded in .3gp h.264 and I am looking to get its framerate and duration in C. Here is the code I use after opening the file and finding the appropriate codecs :

    AVRational rational = gVideoCodecCtx->time_base;

    LOGI(10, "numerator is %i", rational.num);
    LOGI(10, "denominator is %i", rational.den);
    LOGI(10, "duration is %d", gFormatCtx->duration);
    LOGI(10, "fps is %d", (double)av_q2d(rational));

    And here is the output :

    12-02 12:30:19.819: I/FFmpegTest(23903): numerator is 1
    12-02 12:30:19.819: I/FFmpegTest(23903): denominator is 180000
    12-02 12:30:19.819: I/FFmpegTest(23903): duration is 6594490
    12-02 12:30:19.819: I/FFmpegTest(23903): fps is 1692926992

    From the documentation I understand that the duration is meant to be "duration/time_base" which gives me 6594490 / 180000 = 36.6. The duration of my video file is 6 seconds and I do not know where this factor of 6 would come from.

    Also the framerate seems to be completely off.

    It is currenlty hard to find help as a lot of tutorials use deprecated methods and the documentation does not give examples.

    Any help would be appreciated.

    Thanks

    Edit :
    Thanks to the comment below I managed to print the following

    12-02 18:59:36.279: I/FFmpegTest(435): numerator is 1
    12-02 18:59:36.279: I/FFmpegTest(435): denominator is 180000
    12-02 18:59:36.279: I/FFmpegTest(435): duration is 6594490
    12-02 18:59:36.279: I/FFmpegTest(435): fps is 0.000006

    I also managed to find out a frame's timestamp in msec with this :

    int msec = 1000*(packet.pts * timeBase * gVideoCodecCtx->ticks_per_frame);

    This returns me something that's roughly 33fps (I expect 30). But I can't figure out how to retrieve the duration. The documentation says "duration of the stream, in AV_TIME_BASE fractional seconds" but 6594490 * 0.000006 = 39.5 - the correct duration is 6.3 seconds). Also the exact fps is 30 but nor sure how to get from 0.000006 to 30 with the above figures)

    Thanks

  • Tap to record like in vine using javacv

    8 décembre 2015, par human123

    I am trying to implement a tap to record feature like in vine. A sample for handling recording (not touch to record) provided in javacv is https://github.com/bytedeco/javacv/blob/master/samples/RecordActivity.java. I am trying to modify it so that in onPreviewFrame method frames are added to buffer only when user has his finger placed on screen. These frames are then tried to be combined into final video in stopRecording method.

    The issue is that if I set the timestamp as given in below code snippet (in stopRecording method)

    if (t > recorder.getTimestamp())
    {
       recorder.setTimestamp(t);
    }

    the behavior is as below

    Case 1

    If I tap on screen to record for 2 seconds and take the finger away from screen for 3 seconds and then again place finger back on screen to record for another 4 seconds the resulting video is like,

    For 1st 2 seconds video has recorded content. For next 3 seconds (time when finger is put away from screen). video just shows the last frame recorded when finger was placed on screen last. Then the video has recorded video content for next 4 seconds. So there seems to be an issue in handling video recording when finger is removed from screen.

    Case 2

    Next I removed the code setting time stamp to recorder(the code snippet given above) in stopRecording method.

    Now the resulting video (for the same steps tried in case 1) does not contain the middle 3 seconds(which is what is required) when finger was taken away from screen. But video is playing at a faster rate. So it seems that we need to set time stamp so that video plays at normal rate.

    Full code of my activity is given below. (Please note that video recording is mainly handled from onPreviewFrame and stopRecording methods)

    public class TouchToRecordActivity extends Activity implements OnClickListener, View.OnTouchListener {

    private final static String CLASS_LABEL = "TouchToRecordActivity";
    private final static String LOG_TAG = CLASS_LABEL;

    private String ffmpeg_link = "/mnt/sdcard/stream.mp4";

    long startTime = 0;
    boolean recording = false;
    boolean rec = false;

    private FFmpegFrameRecorder recorder;

    private boolean isPreviewOn = false;

    private int sampleAudioRateInHz = 44100;
    private int imageWidth = 640;
    private int imageHeight = 480;
    private int destWidth = 480;
    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 Frame yuvImage = 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;

    /* The number of seconds in the continuous record loop (or 0 to disable loop). */
    final int RECORD_LENGTH = 20;
    Frame[] images;
    long[] timestamps;
    ShortBuffer[] samples;
    int imagesIndex, samplesIndex;

    long firstTime = 0;
    long startPauseTime = 0;
    long totalPauseTime = 0;
    long pausedTime = 0;
    long stopPauseTime = 0;
    long totalTime = 0;

    long totalRecordedTS = 0;

    private TextView txtTimer;
    private Handler mHandler = new Handler();

    @Override
    public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

       setContentView(R.layout.touch_main);

       initLayout();
    }

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

       recording = false;

       if (cameraView != null) {
           cameraView.stopPreview();
       }

       if (cameraDevice != null) {
           cameraDevice.stopPreview();
           cameraDevice.release();
           cameraDevice = 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.touch_main, null);
       layoutParam = new RelativeLayout.LayoutParams(screenWidth, screenHeight);
       topLayout.addView(preViewLayout, layoutParam);

       txtTimer = (TextView) preViewLayout.findViewById(R.id.txtTimer);

       /* 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);
       topLayout.setOnTouchListener(this);
       Log.i(LOG_TAG, "cameara preview start: OK");
    }

    //---------------------------------------
    // initialize ffmpeg_recorder
    //---------------------------------------
    private void initRecorder() {

       Log.w(LOG_TAG, "init recorder");

       if (RECORD_LENGTH > 0) {
           imagesIndex = 0;
           images = new Frame[RECORD_LENGTH * frameRate];
           timestamps = new long[images.length];
           for (int i = 0; i < images.length; i++) {
               images[i] = new Frame(destWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
               timestamps[i] = -1;
           }
       } else if (yuvImage == null) {
           yuvImage = new Frame(destWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
           Log.i(LOG_TAG, "create yuvImage");
       }
       Log.i(LOG_TAG, "ffmpeg_url: " + ffmpeg_link);
       recorder = new FFmpegFrameRecorder(ffmpeg_link, destWidth, imageHeight, 1);
       recorder.setFormat("mp4");
       recorder.setVideoCodecName("libx264");
       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() {

       initRecorder();

       mHandler.removeCallbacks(mUpdateTimeTask);
       mHandler.postDelayed(mUpdateTimeTask, 100);

       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) {
           if (RECORD_LENGTH > 0) {
               Log.v(LOG_TAG, "Writing frames");
               try {
                   int firstIndex = imagesIndex % samples.length;
                   int lastIndex = (imagesIndex - 1) % images.length;
                   if (imagesIndex <= images.length) {
                       firstIndex = 0;
                       lastIndex = imagesIndex - 1;
                   }
                   if ((startTime = timestamps[lastIndex] - RECORD_LENGTH * 1000000L) < 0) {
                       startTime = 0;
                   }
                   if (lastIndex < firstIndex) {
                       lastIndex += images.length;
                   }
                   int videoCounter = 0;
                   for (int i = firstIndex; i <= lastIndex; i++) {
                       if (timestamps[i] == -1) {
                           Log.v(LOG_TAG, "frame not recorded");
                       }
                       if (timestamps[i] != -1) {
                           long t = timestamps[i % timestamps.length] - startTime;
                           if (t >= 0) {

                               videoCounter++;

                               /*if (((i % images.length) != 0) && images[i % images.length] != images[(i % images.length) - 1]) {
                                   if (t > recorder.getTimestamp()) {
                                       recorder.setTimestamp(t);
                                   }*/
                                   Log.v(LOG_TAG, "imageIndex=" + (i % images.length));
                                   recorder.record(images[i % images.length]);
                           /*    }*/
                               Log.v(LOG_TAG, "videoCounter=" + videoCounter);
                           }
                       }
                   }

                   firstIndex = samplesIndex % samples.length;
                   lastIndex = (samplesIndex - 1) % samples.length;
                   if (samplesIndex <= samples.length) {
                       firstIndex = 0;
                       lastIndex = samplesIndex - 1;
                   }
                   if (lastIndex < firstIndex) {
                       lastIndex += samples.length;
                   }
                   for (int i = firstIndex; i <= lastIndex; i++) {
                       if (timestamps[i] != -1) {
                           recorder.recordSamples(samples[i % samples.length]);
                       }
                   }
               } catch (FFmpegFrameRecorder.Exception e) {
                   Log.v(LOG_TAG, e.getMessage());
                   e.printStackTrace();
               }
           }

           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);
    }

    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
       switch (motionEvent.getAction()) {
           case MotionEvent.ACTION_DOWN:
               Log.v(LOG_TAG, "ACTION_DOWN" + recording);

               if (!recording) {
                   startRecording();
               } else {
                   stopPauseTime = System.currentTimeMillis();
                   totalPauseTime = stopPauseTime - startPauseTime - ((long) (1.0 / (double) frameRate) * 1000);
                   pausedTime += totalPauseTime;
               }
               rec = true;
               setTotalVideoTime();
               btnRecorderControl.setText(getResources().getString(R.string.stop));
               break;
           case MotionEvent.ACTION_MOVE:
               rec = true;
               setTotalVideoTime();
               break;
           case MotionEvent.ACTION_UP:
               Log.v(LOG_TAG, "ACTION_UP");
               rec = false;
               startPauseTime = System.currentTimeMillis();
               break;
       }
       return true;
    }

    private Runnable mUpdateTimeTask = new Runnable() {
       public void run() {
           if (recording) {
               setTotalVideoTime();
           }
           mHandler.postDelayed(this, 500);
       }
    };

    private synchronized void setTotalVideoTime() {
       totalTime = System.currentTimeMillis() - firstTime - pausedTime - ((long) (1.0 / (double) frameRate) * 1000);
       if (totalTime > 0)
           txtTimer.setText(getRecordingTimeFromMillis(totalTime));
    }

    private String getRecordingTimeFromMillis(long millis) {
       String strRecordingTime = null;
       int seconds = (int) (millis / 1000);
       int minutes = seconds / 60;
       int hours = minutes / 60;

       if (hours >= 0 && hours < 10)
           strRecordingTime = "0" + hours + ":";
       else
           strRecordingTime = hours + ":";

       if (hours > 0)
           minutes = minutes % 60;

       if (minutes >= 0 && minutes < 10)
           strRecordingTime += "0" + minutes + ":";
       else
           strRecordingTime += minutes + ":";

       seconds = seconds % 60;

       if (seconds >= 0 && seconds < 10)
           strRecordingTime += "0" + seconds;
       else
           strRecordingTime += seconds;

       return strRecordingTime;

    }


    //---------------------------------------------
    // 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;
           ShortBuffer 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);

           if (RECORD_LENGTH > 0) {
               samplesIndex = 0;
               samples = new ShortBuffer[RECORD_LENGTH * sampleAudioRateInHz * 2 / bufferSize + 1];
               for (int i = 0; i < samples.length; i++) {
                   samples[i] = ShortBuffer.allocate(bufferSize);
               }
           } else {
               audioData = ShortBuffer.allocate(bufferSize);
           }

           Log.d(LOG_TAG, "audioRecord.startRecording()");
           audioRecord.startRecording();

           /* ffmpeg_audio encoding loop */
           while (runAudioThread) {
               if (RECORD_LENGTH > 0) {
                   audioData = samples[samplesIndex++ % samples.length];
                   audioData.position(0).limit(0);
               }
               //Log.v(LOG_TAG,"recording? " + recording);
               bufferReadResult = audioRecord.read(audioData.array(), 0, audioData.capacity());
               audioData.limit(bufferReadResult);
               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 && rec) {
                       Log.v(LOG_TAG, "Recording audio");
                       if (RECORD_LENGTH <= 0) try {
                           recorder.recordSamples(audioData);
                           //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) {
           stopPreview();

           Camera.Parameters camParams = mCamera.getParameters();
           List sizes = camParams.getSupportedPreviewSizes();
           // Sort the list in ascending order
           Collections.sort(sizes, new Comparator() {

               public int compare(final Camera.Size a, final Camera.Size b) {
                   return a.width * a.height - b.width * b.height;
               }
           });

           camParams.setPreviewSize(imageWidth, imageHeight);

           Log.v(LOG_TAG, "Setting imageWidth: " + imageWidth + " imageHeight: " + imageHeight + " frameRate: " + frameRate);

           camParams.setPreviewFrameRate(frameRate);
           Log.v(LOG_TAG, "Preview Framerate: " + camParams.getPreviewFrameRate());

           mCamera.setParameters(camParams);

           List videoSizes = mCamera.getParameters().getSupportedVideoSizes();

           // Set the holder (which might have changed) again
           try {
               mCamera.setPreviewDisplay(holder);
               mCamera.setPreviewCallback(CameraView.this);
               startPreview();
           } catch (Exception e) {
               Log.e(LOG_TAG, "Could not set preview display in surfaceChanged");
           }
       }

       @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) {
           if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
               startTime = System.currentTimeMillis();
               return;
           }
           if (RECORD_LENGTH > 0) {
               int i = imagesIndex++ % images.length;
               Log.v(LOG_TAG, "recording:" + recording + "rec:" + rec);
               if (recording && rec) {
                   yuvImage = images[i];
                   timestamps[i] = 1000 * (System.currentTimeMillis() - startTime);
                   totalRecordedTS++;
               } else {
                   Log.v(LOG_TAG, "recording is paused");
                   yuvImage = null;
                   timestamps[i] = -1;
               }
           }

           /* get video data */
           if (yuvImage != null && recording && rec) {
               if (data.length != imageWidth * imageHeight) {
                   Camera.Size sz = camera.getParameters().getPreviewSize();
                   imageWidth = sz.width;
                   imageHeight = sz.height;
                   destWidth = imageHeight;
                   Log.v(LOG_TAG, "data length:" + data.length);
               }

               ByteBuffer bb = (ByteBuffer) yuvImage.image[0].position(0); // resets the buffer
               int start = 2 * ((imageWidth - destWidth) / 4); // this must be even
               for (int row = 0; row < imageHeight * 3 / 2; row++) {
                   bb.put(data, start, destWidth);
                   start += imageWidth;
               }

           }
       }
    }

    @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");
       }
    }}

    Changes made as per Alex Cohn’s suggestions

    Suggestion 1 - Estimate average frame rate

       public void stopRecording() {

      ..............................

                               if (((i % images.length) != 0) && images[i % images.length] != images[(i % images.length) - 1]) {
                                   if (t > recorder.getTimestamp()) {
                                       t += 1000000 / frameRate;
                                       recorder.setTimestamp(t);
                                   }

                                   recorder.record(images[i % images.length]);
                               }
                ..........................................


    }

    Change made was adding t += 1000000 / frameRate ; But this caused the video to freeze (as in case 1 described above) in portions when finger was placed away from screen.

    Suggestion 2 - Modification in onPreviewFrame()

    long[] timestampsForRecorder;
    private void initRecorder() {

       Log.w(LOG_TAG, "init recorder");

       if (RECORD_LENGTH > 0) {
          .......................................................
           timestampsForRecorder = new long[images.length];
           for (int i = 0; i < images.length; i++) {
               images[i] = new Frame(destWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
               timestamps[i] = -1;
               timestampsForRecorder[i] = -1;
           }
       } else if (yuvImage == null) {
           yuvImage = new Frame(destWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
           Log.i(LOG_TAG, "create yuvImage");
       }
       ...................................................
    }

    @Override
    public void onPreviewFrame(byte[] data, Camera camera) {
           if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
               startTime = SystemClock.elapsedRealtime();
               return;
           }
           if (RECORD_LENGTH > 0) {
               int i = imagesIndex++ % images.length;
               Log.v(LOG_TAG, "recording:" + recording + "rec:" + rec);
               if (recording && rec) {
                   yuvImage = images[i];
                   long thisFrameTime = SystemClock.elapsedRealtime();
                   timestamps[i] = thisFrameTime;
                   long lastFrameTime = timestamps[(int) (imagesIndex == 0 ? startTime : ((imagesIndex-1) % images.length))];
                   Log.v(LOG_TAG, "lastFrameTime:" + lastFrameTime+",stopPauseTime:" + stopPauseTime);
                   if (lastFrameTime > stopPauseTime) {
                       timestampsForRecorder[i] = 1000 * (thisFrameTime - Math.max(stopPauseTime, lastFrameTime));
                   }
               }
           }

          .....................................................
       }

    public void stopRecording() {

       .......................................................

       if (recorder != null && recording) {
           if (RECORD_LENGTH > 0) {
               Log.v(LOG_TAG, "Writing frames");
               try {
                   int firstIndex = imagesIndex % samples.length;
                   int lastIndex = (imagesIndex - 1) % images.length;
                   if (imagesIndex <= images.length) {
                       firstIndex = 0;
                       lastIndex = imagesIndex - 1;
                   }
                   if ((startTime = timestampsForRecorder[lastIndex] - RECORD_LENGTH * 1000000L) < 0) {
                       startTime = 0;
                   }
                   if (lastIndex < firstIndex) {
                       lastIndex += images.length;
                   }
                   for (int i = firstIndex; i <= lastIndex; i++) {

                       if (timestampsForRecorder[i] != -1) {
                           long t = timestampsForRecorder[i % timestampsForRecorder.length] - startTime;
                           if (t >= 0) {

                               if (((i % images.length) != 0) && images[i % images.length] != images[(i % images.length) - 1]) {
                                   if (t > recorder.getTimestamp()) {
                                       recorder.setTimestamp(t);
                                   }
                                   Log.v(LOG_TAG, "imageIndex=" + (i % images.length));
                                   recorder.record(images[i % images.length]);
                               }
                           }
                       }
                   }
                   .............................................
               } catch (FFmpegFrameRecorder.Exception e) {
                  .................................
               }
           }

           ...........................................

       }
    }

    The video recorded using this was having the issue in case 2 mentioned above. ie,It was playing at a faster rate

  • Issue in recording video

    16 novembre 2015, par human123

    I am trying to record video in 480*480 resolution like in vine using javacv. As a starting point I used the sample provided in https://github.com/bytedeco/javacv/blob/master/samples/RecordActivity.java Video is getting recorded (but not in the desired resolution) and saved.

    But the issue is that 480*480 resolution is not supported natively in android. So some pre processing needs to be done to get the video in desired resolution.

    So once I was able to record video using code sample provided by javacv, next challenge was on how to pre process the video. On research it was found that efficient cropping is possible when final image width required is same as recorded image width. Such a solution was provided in the SO question,Recording video on Android using JavaCV (Updated 2014 02 17). I changed onPreviewFrame method as suggested in that answer.

       @Override
       public void onPreviewFrame(byte[] data, Camera camera) {
           if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
               startTime = System.currentTimeMillis();
               return;
           }
           if (RECORD_LENGTH > 0) {
               int i = imagesIndex++ % images.length;
               yuvImage = images[i];
               timestamps[i] = 1000 * (System.currentTimeMillis() - startTime);
           }
           /* get video data */
           imageWidth = 640;
           imageHeight = 480    
           int finalImageHeight = 360;
           if (yuvImage != null && recording) {
               ByteBuffer bb = (ByteBuffer)yuvImage.image[0].position(0); // resets the buffer
               final int startY = imageWidth*(imageHeight-finalImageHeight)/2;
               final int lenY = imageWidth*finalImageHeight;
               bb.put(data, startY, lenY);
               final int startVU = imageWidth*imageHeight + imageWidth*(imageHeight-finalImageHeight)/4;
               final int lenVU = imageWidth* finalImageHeight/2;
               bb.put(data, startVU, lenVU);
               try {
                   long t = 1000 * (System.currentTimeMillis() - startTime);
                   if (t > recorder.getTimestamp()) {
                       recorder.setTimestamp(t);
                   }
                   recorder.record(yuvImage);
               } catch (FFmpegFrameRecorder.Exception e) {
                   Log.e(LOG_TAG, "problem with recorder():", e);
               }
           }


       }
    }

    Please also note that this solution was provided for an older version of javacv. The resulting video had a yellowish overlay covering 2/3rd part. Also there was empty section on left side as the video was not cropped correctly.

    So my question is what is the most appropriate solution for cropping videos using latest version of javacv ?

    Code after making change as suggested by Alex Cohn

       @Override
       public void onPreviewFrame(byte[] data, Camera camera) {
           if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
               startTime = System.currentTimeMillis();
               return;
           }
           if (RECORD_LENGTH > 0) {
               int i = imagesIndex++ % images.length;
               yuvImage = images[i];
               timestamps[i] = 1000 * (System.currentTimeMillis() - startTime);
           }
           /* get video data */
           imageWidth = 640;
           imageHeight = 480;      
           destWidth = 480;

           if (yuvImage != null && recording) {
               ByteBuffer bb = (ByteBuffer)yuvImage.image[0].position(0); // resets the buffer
               int start = 2*((imageWidth-destWidth)/4); // this must be even
               for (int row=0; row2; row++) {
                   bb.put(data, start, destWidth);
                   start += imageWidth;
               }
               try {
                   long t = 1000 * (System.currentTimeMillis() - startTime);
                   if (t > recorder.getTimestamp()) {
                       recorder.setTimestamp(t);
                   }
                   recorder.record(yuvImage);
               } catch (FFmpegFrameRecorder.Exception e) {
                   Log.e(LOG_TAG, "problem with recorder():", e);
               }
           }


       }

    Screen shot from video generated with this code (destWidth 480) is

    video resolution 480*480

    Next I tried capturing a video with destWidth speciified as 639. The result is

    639*480

    When destWidth is 639 video is repeating contents twice. When it is 480, contents are repeated 5 times and the green overlay and distortion is more.

    Also When the destWidth = imageWidth, video is captured properly. ie, for 640*480 there is no repetition of video contents and no green overlay.

    Converting frame to IplImage

    When this question was asked first, I missed to mention that the record method in FFmpegFrameRecorder is now accepting object of type Frame whereas earlier it was IplImage object. So I tried to apply Alex Cohn’s solution by converting Frame to IplImage.

    //---------------------------------------
    // initialize ffmpeg_recorder
    //---------------------------------------
    private void initRecorder() {

       Log.w(LOG_TAG,"init recorder");

       imageWidth = 640;
       imageHeight = 480;

       if (RECORD_LENGTH > 0) {
           imagesIndex = 0;
           images = new Frame[RECORD_LENGTH * frameRate];
           timestamps = new long[images.length];
           for (int i = 0; i < images.length; i++) {
               images[i] = new Frame(imageWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
               timestamps[i] = -1;
           }
       } else if (yuvImage == null) {
           yuvImage = new Frame(imageWidth, imageHeight, Frame.DEPTH_UBYTE, 2);
           Log.i(LOG_TAG, "create yuvImage");
           OpenCVFrameConverter.ToIplImage converter = new OpenCVFrameConverter.ToIplImage();
           yuvIplimage = converter.convert(yuvImage);

       }

       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;
    }



    @Override
       public void onPreviewFrame(byte[] data, Camera camera) {
           if (audioRecord == null || audioRecord.getRecordingState() != AudioRecord.RECORDSTATE_RECORDING) {
               startTime = System.currentTimeMillis();
               return;
           }
           if (RECORD_LENGTH > 0) {
               int i = imagesIndex++ % images.length;
               yuvImage = images[i];
               timestamps[i] = 1000 * (System.currentTimeMillis() - startTime);
           }
           /* get video data */
           int destWidth = 640;

           if (yuvIplimage != null && recording) {
               ByteBuffer bb = yuvIplimage.getByteBuffer(); // resets the buffer
               int start = 2*((imageWidth-destWidth)/4); // this must be even
               for (int row=0; row2; row++) {
                   bb.put(data, start, destWidth);
                   start += imageWidth;
               }
               try {
                   long t = 1000 * (System.currentTimeMillis() - startTime);
                   if (t > recorder.getTimestamp()) {
                       recorder.setTimestamp(t);
                   }
                   recorder.record(yuvImage);
               } catch (FFmpegFrameRecorder.Exception e) {
                   Log.e(LOG_TAG, "problem with recorder():", e);
               }
           }


       }

    But the videos generated with this method contained only green frames.