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• How to convert a mp4 video file to H.264 format programatically in Android ?

  25 janvier 2016, par Omair Aslam

  I want convert a mp4 file to H.264 format. I am using Video view to play my video in android. The video view is getting the video from video path.

  Currently this is working in Android 4.2.2 and above but while testing it in 4.2.1 it shows a black screen, and video player plays but with black screen.

  The 4.2.1 devise plays videos perfectly in its default player , the format that it uses is H.264. So i would like to know how at runtime i decide that if video view is showing black screen , it converts it too H.264 format and then play, and in normal scenarios it should not convert and just play the normal mp4 format video.

  My code is below
  `

  File file = TimeBom.getInstance().GetCurrentFile();
  
                      if(file.exists()){
  
  if (mediaControls == null) {
  
                               mediaControls = new MediaController(getActivity());
  
                           }
  
  DialogsController.getInstance().ShowProgressDialogBox("Loading Video...");
  
  
  
                                   //we also set an setOnPreparedListener in order to know when the video file is ready for playback
  
                               videoView.setOnPreparedListener(new OnPreparedListener() {
  
  
  
                                   public void onPrepared(MediaPlayer mediaPlayer) {
  
                                       // close the progress bar and play the video
  
                                       DialogsController.getInstance().HideProgressDialogBox();
  
                                       //if we have a position on savedInstanceState, the video playback should start from here
  
                                       videoView.seekTo(position);
  
                                       if (position == 0) {
  
                                           videoView.start();
  
                                       } else {
  
                                           //if we come from a resumed activity, video playback will be paused
  
                                           videoView.pause();
  
                                       }
  
                                   }
  
                               });
  
  
  
                               videoView.setOnCompletionListener(new OnCompletionListener() {
  
  
  
                                  @Override
  
                                  public void onCompletion(MediaPlayer arg0) {
  
                                      // TODO Auto-generated method stub
  
                                      FragmentsController.getInstance().popCurrentFragment(true);
  
                                  }
  
                              });
  
  
  
                               videoView.setOnErrorListener(new OnErrorListener() {
  
  
  
                                  @Override
  
                                  public boolean onError(MediaPlayer mp, int what, int extra) {
  
                                      // TODO Auto-generated method stub
  
                                      DialogsController.getInstance().HideProgressDialogBox();
  
                                      switch(extra){
  
                                      case MediaPlayer.MEDIA_ERROR_UNSUPPORTED:
  
                                          DialogsController.getInstance().ShowSimpleMessageDialogBox("Error,Unsupported Video!");
  
                                          break;
  
                                      case MediaPlayer.MEDIA_ERROR_MALFORMED:
  
                                          DialogsController.getInstance().ShowSimpleMessageDialogBox("Error,Malformed!");
  
                                          break;
  
                                      case MediaPlayer.MEDIA_ERROR_UNKNOWN:
  
                                          DialogsController.getInstance().ShowSimpleMessageDialogBox("Error,Unknown Error!");
  
                                          break;
  
  
  
                                      }
  
                                      return false;
  
                                  }
  
                              });
  
                               try {
  
                                   //set the media controller in the VideoView
  
                                   videoView.requestFocus();
  
  
  
                                   videoView.setMediaController(mediaControls);
  
  
  
  
  
                                   //set the uri of the video to be played
  
                                  videoView.setVideoPath(file.getAbsolutePath());
  
  
  
                               } catch (Exception e) {
  
                                   Log.e("Error", e.getMessage());
  
                                   e.printStackTrace();
  
                               }
  
                          }
  
                          else{
  
                              Utilities.getInstance().ShowToast("Video does not exists!");
  
                          }

  `
  One more thing is that for un supported format exception is not raised by video view, it just shows black screen.
  So it would be really helpfull if any one tell me how can i convert it to H.264 format,
  Thanks in advance

• ffmpeg : Continuous streaming plus recording at random time

  21 juin 2014, par Ralf Anderson

  It’s possible to stream and record the same input at the same time with ffmpeg. What I want to do though, is only start (and stop) recording at some random point later.

  Is it possible to somehow tell the active ffmpeg process (which is already streaming) to also start recording ?
  My first alternative was to simply start another ffmpeg process just to record, but the source input will be blocked by the first ffmpeg process streaming it and the stream will be blocked by the viewer displaying the stream on screen, so I can’t access anything to record. Can I change something so the stream/source input is not reserved for just one receiver ?

  In my concrete scenario, the source input is a webcam, which I want to continuously display plus be able to record at user-driven time. I stream the webcam using ffmpeg via udp to the localhost and can view it with a suitable player. I just can’t record it while also viewing and vice versa.

  I also tried the "Tee Muxer", which can generate multiple outputs with the same ffmpeg instance. I streamed it to the localhost on different ports, one to view and one to record.

  ffmpeg.exe -f dshow -i video="ManyCam Virtual Webcam" -map 0 -vcodec h264 -r 25 -f tee "[f=mpegts]udp://127.0.0.1:33333/|[f=mpegts]udp://127.0.0.1:33334/"

  This works fine, except for the delay of about 500ms, which I only get when I stream, not when I access the Webcam directly with ffplay e.g.. I was expecting no delay at all, since it’s all local, but I suppose this comes from the encoding ? I’ve tried streaming the raw video (setting -vcodec rawvideo), but I can neither view it with ffplay nor record it. Are there some special parameters needed for rawvideo ? After all, the input for the stream is rawvideo too, according to ffmpeg.

  I have not yet looked at ffserver, but I assume it would be no different to generating multiple outputs with tee muxer in my use case ?

  If I somehow could be able to display/record the stream generated by

  ffmpeg.exe -f dshow -i video="ManyCam Virtual Webcam" -map 0 -vcodec rawvideo -r 25 -f tee "[f=mpegts]udp://127.0.0.1:33333/|[f=mpegts]udp://127.0.0.1:33334/"

  then that would already suffice. Or changing the encoding in such a way that no compression is done at all should work just as well (if that’s causing the delay).

• Streaming video with node

  14 septembre 2016, par Kei Taylor

  I am attempting to stream video with from my built-in Mac OSX webcam to a node server. My intent is to parse the video data I receive with ffmpeg once it reaches the server. This is my first time trying to manipulate video.

  My problem is, right now I am unable to use VLC to send data to a node server. I am opening a stream with VLC by using the "Open Network" option, and streaming through what I think is my local IP, port 3000. However, I am not sure how to get from that to opening the stream on a node file. Also, I am not able to open the stream on the same computer and view it (I mean, when I click open stream on VLC and plug in my local IP and port 3000, I can’t view the stream I’m sending out).

  Clearly, I am doing something wrong. As this is my first experience with VLC and video transmission, its possible I’m missing something important. Its my impression that I should be able to stream to an ip and port using VLC, and then set up a node server that listens for data from this same port and ip, recieves chunks of video data, and formats it using FFMPEG.

  My questions are :

  1) Is this understanding accurate ?
  2) Does anyone have guidance on how I would transmit with VLC and read with FFMPEG in node (and then send to another client ?)
  3) Failing that, any guidance on the simple question of how to transmit a video stream using VLC and then open it using VLC on the same computer ?
  4) Any resources explaining how to do this ?

  I’d really appreciate layman’s, baby explanations. I’ve found a few blog posts that have illuminated issues, but been a bit difficult to follow.

  Thanks, as always.