Recherche avancée

Sur d’autres sites (3272)

• H264 to MP4 with Bframe play back and forth on google chrome[ffmpeg]

  2 mai 2017, par Ravi Agola

  I want to generate a mp4 container with h264 encoded file.

  H264 file contains [I P B B][P B B][P B B][P B B] frames.

  when I generate a mp4 file with FFmpeg, It works well with FFplay as well as VLC but on google-chrome mp4 file plays frame back and forth.

  ffmpeg -i input.h264 -vcodec copy output.mp4

  when i use internal codec library(libx264) it works well on (ffplay,vlc and google-chrome)

  ffmpeg -i input.h264 -vcodec h264 output.mp4

  as above command transcode h264(native) to h264(x264), I don’t want to transcode file as I will be using it with ffmpeg library.

  when I use h264 without B frame it works well in both cases.

  I have tried some experiment with sample test file available here.

  direct conversion(MKV to MP4) works well with chrome as below

  ffmpeg -i jellyfish-3-mbps-hd-h264.mkv -vcodec copy output.mp4

  (MKV to H264 and H264 to MP4) plays back and forth on chrome

  ffmpeg -i jellyfish-3-mbps-hd-h264.mkv -vcodec copy output.h264
  ffmpeg -i output.h264 -vcodec copy output.mp4

  I get message in this case
  [mp4 @ 0xb6f8b20] Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
  [mp4 @ 0xb6f8b20] pts has no value"

  what can be a reason behind this behavior ?

  Thanks.

• FFmpegMediaPlayer Stops When Network is Turned Off and Back On

  18 mai 2017, par Fallas

  I am currently working with FFmpegMediaPlayer in order to make a basic music player given a url. I got the basic functionality to work. On error, I show an error message, else I play the songs.
  The problem I am facing is, once the player starts, and I turn off my wifi and phone data, it stops the sound. Once I turn my wifi or phone data back one, I would like the player to continue but it simply stops. I have to stop and play again for it to continue.

  Is there a way to have the FFmpegMediaPlayer continue streaming ?

  This is what I have to initialize the player :

  mMediaPlayer = new FFmpegMediaPlayer();
  
      mMediaPlayer.setOnErrorListener(this);
  
      mMediaPlayer.setOnPreparedListener(this);
  
      mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
  
      mMediaPlayer.setOnBufferingUpdateListener(this);
  
      mMediaPlayer.setOnSeekCompleteListener(this);
  
  
  
      try {
  
          Uri uri = Uri.parse(radio_url);
  
          mMediaPlayer.setDataSource(mMainActivity, uri);
  
          mMediaPlayer.prepareAsync();
  
      } catch (IllegalArgumentException e) {
  
          e.printStackTrace();
  
      } catch (SecurityException e) {
  
          e.printStackTrace();
  
      } catch (IllegalStateException e) {
  
          e.printStackTrace();
  
      } catch (IOException e) {
  
          e.printStackTrace();
  
      }

  Then I have a function to handle when Play/Stop button is clicked :

  @Override
  
  public void onPlayButtonClicked(Button button) {
  
  
  
      if (radioInitialized) {
  
          mAnalytics.onStopButtonClicked();
  
          mMainLayout.loading(false);
  
          mMediaPlayer.pause();
  
       button.setBackground(mMainActivity.getResources().getDrawable(R.drawable.play_button));
  
          radioInitialized = false;
  
      } else {
  
          mAnalytics.onPlayButtonClicked();
  
          mMainLayout.loading(true);
  
          initRadio();
  
          button.setBackground(mMainActivity.getResources().getDrawable(R.drawable.stop_button));
  
          radioInitialized = true;
  
      }
  
  }

  Again, the basic functionality works, but I would like for it to continue streaming after wifi is turned back on.

• Looping back and forth through frames with ffmpeg

  18 mai 2017, par sebb

  I have a set of ten PNG frames that I’d like to convert to a "boomerang style" mp4 file (i.e go from frame 1 to frame 10, then from 9 to 2). I’d like to find something similar to ImageMagick’s patrol cycle, but can’t figure out how to to it with ffmpeg.

  I thought it would be possible to do this using concat but :

  • I think it’s dirty
  • My command simply does not work :)

  Here’s my command so far :

  -framerate 5 -i "concat:01.png|02.png|03.png|04.png|05.png|06.png|07.png|08.png|09.png|10.png|09.png|08.png|07.png|06.png|05.png|04.png|03.png|02.png" -pix_fmt yuv420p output.mp4

  I get a video file but it just goes from 1 to 10 once.

  Here’s ffmpeg’s saying hello :

  ffmpeg version N-86098-g3fefaea Copyright (c) 2000-2017 the FFmpeg developers
  
  
  
    built with gcc 6.3.0 (GCC)
  
  
  
    configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-zlib
  
  
  
    libavutil      55. 63.100 / 55. 63.100
  
  
  
    libavcodec     57. 96.101 / 57. 96.101
  
  
  
    libavformat    57. 72.101 / 57. 72.101
  
  
  
    libavdevice    57.  7.100 / 57.  7.100
  
  
  
    libavfilter     6. 89.101 /  6. 89.101
  
  
  
    libswscale      4.  7.101 /  4.  7.101
  
  
  
    libswresample   2.  8.100 /  2.  8.100
  
  
  
    libpostproc    54.  6.100 / 54.  6.100

  Anyone has an idea ?

  Thanks !