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• No such file or directory - ffmpegthumbnailer

  8 juin 2016, par kajal

  File Failed to thumbnail with ffmpegthumbnailer. Check ffmpegthumbnailer install and verify video is not corrupt. Original error: No such file or directory - ffmpegthumbnailer

• FFmpeg is giving me nightmares

  8 juin 2016, par Guillermo

  So, I'm trying to save animations with the animation.save command. I installed ffmpeg in Windows 10 by placing a folder with its binaries in my drive C:\, I have also set the path in my system variables like C:\ffmpeg\bin, and finally, my code for the animation function saving looks like this

   if save=='True':
       mywriter = animation.FFMpegWriter()
       plt.rcParams['animation.ffmpeg_path'] = 'C:/ffmpeg/bin' 
       ani.save('mymovie.avi',writer=mywriter,fps=30)
  

  and all other kind of variants such as:

      mpl.animation.ffmpeg_path = r'C:\ffmpeg\bin' 
      mpl.animation.ffmpeg_path = 'C:\\ffmpeg\\bin' 
  

  No matter what I do, the result is always:

  File "", line 2, in 
  File "Plot.py", line 168, in animate
  ani.save('mymovie.avi',writer=mywriter,fps=30)
  File "c:\users\guillermo\appdata\local\enthought\canopy\user\lib\site-packages\matplotlib\animation.py", line 801, in save
  with writer.saving(self._fig, filename, dpi):
  File "C:\Users\Guillermo\AppData\Local\Enthought\Canopy\App\appdata\canopy-1.6.1.3253.win-x86_64\lib\contextlib.py", line 17, in __enter__
  return self.gen.next()
  File "c:\users\guillermo\appdata\local\enthought\canopy\user\lib\site-packages\matplotlib\animation.py", line 194, in saving
  self.setup(*args)
  File "c:\users\guillermo\appdata\local\enthought\canopy\user\lib\site-packages\matplotlib\animation.py", line 184, in setup
  self._run()
  File "c:\users\guillermo\appdata\local\enthought\canopy\user\lib\site-packages\matplotlib\animation.py", line 212, in _run
  creationflags=subprocess_creation_flags)
  File "C:\Users\Guillermo\AppData\Local\Enthought\Canopy\App\appdata\canopy-1.6.1.3253.win-x86_64\lib\subprocess.py", line 710, in __init__
  errread, errwrite)
  File "C:\Users\Guillermo\AppData\Local\Enthought\Canopy\App\appdata\canopy-1.6.1.3253.win-x86_64\lib\subprocess.py", line 958, in _execute_child
  startupinfo)
  WindowsError: [Error 5] Access Denied
  

  Any ideas? :D

  ------------------------------------------------------------------------------

  EDIT: I will reference this answer as it is the one that helped me the best: http://stackoverflow.com/a/27017734/6050676

  It worked perfectly when using:

  plt.rcParams['animation.ffmpeg_path'] = 'C:\\ffmpeg\\bin\\ffmpeg.exe'  
  

• FFMpeg copy streams without transcode

  8 juin 2016, par Zelid

  I'm trying to copy all streams from several files into one file without transcoding streams. Something you usually do with ffmpeg utility by ffmpeg -i “file_with_audio.mp4” -i “file_with_video.mp4” -c copy -shortest file_with_audio_and_video.mp4

  This is the code:

  int ffmpegOpenInputFile(const char* filename, AVFormatContext **ic) {
  
      int ret;
      unsigned int i;
  
      *ic = avformat_alloc_context();
      if (!(*ic))
          return -1; // Couldn't allocate input context
  
      if((ret = avformat_open_input(ic, filename, NULL, NULL)) < 0)
          return ret; // Couldn't open file
  
      // Get format info (retrieve stream information)
      if ((ret = avformat_find_stream_info(*ic, NULL)) < 0)
          return ret; // Couldn't find stream information
  
      for (int i = 0; i < (*ic)->nb_streams; i++) {
          AVStream *stream;
          AVCodecContext *codec_ctx;
          stream = (*ic)->streams[i];
          codec_ctx = stream->codec;
          /* Reencode video & audio and remux subtitles etc. */
          if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO
              || codec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
              /* Open decoder */
              ret = avcodec_open2(codec_ctx,
                                  avcodec_find_decoder(codec_ctx->codec_id), NULL);
              if (ret < 0) {
                  av_log(NULL, AV_LOG_ERROR, "Failed to open decoder for stream #%u\n", i);
                  return ret;
              }
          }
      }
  
      // Dump information about file onto standard error
      av_dump_format(*ic, 0, filename, 0);
  
      return 0;
  }
  
  
  
  int main(int argc, char *argv[]) {
  
      const char *inputFilename1 = "/avfiles/video_input.mp4";
      const char *inputFilename2 = "/avfiles/audio_input.mp4";
      const char *filename = "/avfiles/out.mp4";
  
      int ret;
  
      av_register_all();
  
      AVFormatContext *ic1 = nullptr;
      AVFormatContext *ic2 = nullptr;
      AVFormatContext *oc = nullptr;
  
      if ((ret = ffmpegOpenInputFile(inputFilename1, &ic1)) < 0)
          return ret;  // and free resources and
  
      if ((ret = ffmpegOpenInputFile(inputFilename2, &ic2)) < 0)
          return ret;  // and free resources and
  
      AVOutputFormat *outfmt = av_guess_format(NULL, filename, NULL);
      if (outfmt == NULL)
          return -1;  // Could not guess output format
  
      avformat_alloc_output_context2(&oc, outfmt, NULL, filename);
      if (!oc)
          return AVERROR_UNKNOWN;  // Could not create output context
  
      // populate input streams from all input files
      AVStream **input_streams = NULL;
      int nb_input_streams = 0;
      for (int i = 0; i < ic1->nb_streams; i++) {
          input_streams = (AVStream **) grow_array(input_streams, sizeof(*input_streams), &nb_input_streams,
                                                   nb_input_streams + 1);
          input_streams[nb_input_streams - 1] = ic1->streams[i];
      }
      for (int i = 0; i < ic2->nb_streams; i++) {
          input_streams = (AVStream **) grow_array(input_streams, sizeof(*input_streams), &nb_input_streams,
                                                   nb_input_streams + 1);
          input_streams[nb_input_streams - 1] = ic2->streams[i];
      }
  
      for (int i = 0; i < nb_input_streams; i++) {
          AVStream *ist = input_streams[i];  // could be named 'm_in_vid_strm'
  
          // if output context has video codec support and current input stream is video
          if (/*oc->video_codec_id*/ oc->oformat->video_codec != AV_CODEC_ID_NONE && ist != NULL
                                     && ist->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
  
              AVCodec *out_vid_codec = avcodec_find_encoder(oc->oformat->video_codec);
              if (NULL == out_vid_codec)
                  return -1;  // Couldn't find video encoder
  
              AVStream *m_out_vid_strm = avformat_new_stream(oc, out_vid_codec);
              if (NULL == m_out_vid_strm)
                  return -1;  // Couldn't output video stream
  
              m_out_vid_strm->id = 0;  // XXX:
  
              ret = avcodec_copy_context(m_out_vid_strm->codec, ist->codec);
              if (ret < 0)
                  return ret;  // Failed to copy context
  
          }
  
          // if output context has audio codec support and current input stream is audio
          if (/*oc->audio_codec_id*/ oc->oformat->audio_codec != AV_CODEC_ID_NONE && ist != NULL
                                     && ist->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
  
              AVCodec *out_aud_codec = avcodec_find_encoder(oc->oformat->audio_codec);
              if (nullptr == out_aud_codec)
                  return -1;  // couldn't find audio codec
  
              AVStream *m_out_aud_strm = avformat_new_stream(oc, out_aud_codec);
              if (nullptr == m_out_aud_strm)
                  return -1;  // couldn't allocate audio out stream
  
              ret = avcodec_copy_context(m_out_aud_strm->codec, ist->codec);
              if (ret < 0)
                  return ret;  // couldn't copy context
  
          }
      }
  
      // finally output header
      if (!(oc->flags & AVFMT_NOFILE)) {
  
          ret = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE);
          if (ret < 0)
              return ret;  // Could not open output file
  
          av_dump_format(oc, 0, filename, 1);
  
          ret = avformat_write_header(oc, NULL);
          if (ret < 0)
              return ret; // Error occurred when opening output file
  
      }
  
      return 0;
  
  }
  

  avformat_write_header(oc, NULL); always return error and I see this messages:

  [mp4 @ 0x7f84ec900a00] Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead.
  [mp4 @ 0x7f84ec900a00] Tag avc1/0x31637661 incompatible with output codec id '28' ([33][0][0][0])
  

  But input and output streams match:

  Input streams from 2 files:
  Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 2834 kb/s, 23.98 fps, 23.98 tbr, 90k tbn, 47.95 tbc (default)
  Stream #0:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s (default)
  
  Output #0, mp4, to '/Users/alex/Workspace/_qt/tubisto/avfiles/out.mp4':
      Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 2834 kb/s, 47.95 tbc
      Stream #0:1: Audio: aac (libvo_aacenc) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s
  

  Why the error with incompatible output codec happens? What is wrong in my code and how to make it work to copy all streams from all input files to output file?

• I want to merge two videos in golang . How can i do that ? [on hold]

  8 juin 2016, par Kiran007

  Please provide me ways to do it.Any related Links would be helpful.

• Android Video color effect issue using FFMPEG [on hold]

  8 juin 2016, par umesh mishra

  I m facing one problem. when we use library for effect that i have mentioned below video is created only 1/3 of actual video size. please tell me what is issue. and also doesn't work on marshmallow. https://github.com/krazykira/VidEffects/wiki/Permanent-video-effects