Recherche avancée

Sur d’autres sites (10004)

• saving ffmpeg output in a file field in django using tempfiles

  27 janvier 2017, par StarLord

  I am trying to extract audio from video when uploaded, and store it in a different model.

  this is the task code :

  def set_metadata(input_file, video_id):
  
      """
  
      Takes the file path and video id, sets the metadata and audio
  
      :param input_file: file url or file path
  
      :param video_id: video id of the file
  
      :return: True
  
      """
  
      # extract metadata
  
      command = [FFPROBE_BIN,
  
                 '-v', 'quiet',
  
                 '-print_format', 'json',
  
                 '-show_format',
  
                 '-show_streams',
  
                 '-select_streams', 'v:0',
  
                 input_file]
  
      output = sp.check_output(command)
  
      output = output.decode('utf-8')
  
      metadata_output = json.loads(output)
  
      video_instance = Video.objects.get(pk=video_id)
  
      stream = metadata_output['streams'][0]
  
      tot_frames_junk = int(stream['avg_frame_rate'].split("/")[0])
  
      tot_time_junk = int(stream['avg_frame_rate'].split("/")[1])
  
      # update the video model with newly acquired metadata
  
      video_instance.width = stream['width']
  
      video_instance.height = stream['height']
  
      video_instance.frame_rate = tot_frames_junk/tot_time_junk
  
      video_instance.duration = stream['duration']
  
      video_instance.total_frames = stream['nb_frames']
  
      video_instance.video_codec = stream['codec_name']
  
      video_instance.save()
  
  
  
      # extract audio
  
      tmpfile = temp.NamedTemporaryFile(suffix='.mp2')
  
      command = ['ffmpeg',
  
                 '-y',
  
                 '-i', input_file,
  
                 '-loglevel', 'quiet',
  
                 '-acodec', 'copy',
  
                 tmpfile.name]
  
      sp.check_output(command)
  
      audio_obj = Audio.objects.create(title='awesome', audio=tmpfile)
  
      audio_obj.save()

  I am passing video object id and the file path to the method. The file path is a url from azure storage.

  The part where I am processing for metadata, it works and the video object gets updated. But the audio model is not created.

  It throws this error :

  AttributeError("'_io.BufferedRandom' object has no attribute '_committed'",)

  at command :

  audio_obj = Audio.objects.create(title='awesome', audio=tmpfile)

  What am I doing wrong with the temp file.

• avfilter/avfilter : add a side_data field to AVFilterLink

  25 mars 2024, par James Almer

  avfilter/avfilter : add a side_data field to AVFilterLink
  This will be used to propagate global side data through the filterchain.
  Signed-off-by : James Almer <jamrial@gmail.com>
  

  • [DH] doc/APIchanges
  • [DH] libavfilter/avfilter.c
  • [DH] libavfilter/avfilter.h
  • [DH] libavfilter/version.h

• Lossless codec for bayer data

  21 août 2016, par vhdirk

  I’m working with lots of camera’s which capture in BG bayer pattern natively.

  Now, every time I record some data, I save it to the disk in the raw bayer pattern, in an avi container. The problem is, that this really adds up after a while. After one year of research, I have close to 4TB of data...

  So I’m looking for a lossless codec to compress this data. I know I could use libx264 (with —qp 0), or huffYUV, dirac or jpeg2000, but they all assume you have RGB or YUV data. It’s easy enough to convert the bayered data to RGB, and then compress it, but it kind of defeats the purpose of compression if you first triple the data. This would also mean that the demoasicing artefacts introduced by debayering would also be in my source data, which is also not too great. It would be nice to have a codec that can work on the bayered data directly.

  Even more nice would be that the solution would involve a codec that is already supported by gstreamer (or ffmpeg), since that’s what I am already using.