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• Can I convert a django video upload from a form using ffmpeg before storing the video ?

  5 mai 2014, par GetItDone

  I’ve been stuck for weeks trying to use ffmpeg to convert user uploaded videos to flv. I use heroku to host my website, and store my static and media files on amazon S3 with s3boto. The initial video file will upload fine, however when I retrieve the video and run a celery task (in the same view where the initial video file is uploaded), the new file won’t store on S3. I’ve been trying to get this to work for over a month, with no luck, and really no good resources available for learning how to do this, so I figure maybe if I can get the ffmpeg task to run before storing the video I may be able to get it to work. Unfortunately I’m still not a very advanced at python (or django), so I don’t even know if/how this is possible. Anyone have any ideas ? I am willing to use any solution at this point no matter how ugly, as long as it successfully takes video uploads and converts to flv using ffmpeg, with the resulting file being stored on S3. It doesn’t seem that my situation is very common, because no matter where I look, I cannot find a solution that explains what I should be trying to do. Therefore I will be very appreciative of any guidance. Thanks. My relevant code follows :

  #models.py
  
  def content_file_name(instance, filename):
  
      ext = filename.split('.')[-1]
  
      new_file_name = "remove%s.%s" % (uuid.uuid4(), ext)
  
      return '/'.join(['videos', instance.teacher.username, new_file_name])
  
  
  
  class BroadcastUpload(models.Model):
  
      title = models.CharField(max_length=50, verbose_name=_('Title'))
  
      description = models.TextField(max_length=100, verbose_name=_('Description'))
  
      teacher = models.ForeignKey(User, null=True, blank=True, related_name='teacher')
  
      created_date = models.DateTimeField(auto_now_add=True)
  
      video_upload = models.FileField(upload_to=content_file_name)
  
      flvfilename = models.CharField(max_length=100, null=True, blank=True)
  
      videothumbnail = models.CharField(max_length=100, null=True, blank=True)
  
  
  
  #tasks.py
  
  @task(name='celeryfiles.tasks.convert_flv')
  
  def convert_flv(video_id):
  
      video = BroadcastUpload.objects.get(pk=video_id)
  
      print "ID: %s" % video.id
  
      id = video.id
  
      print "VIDEO NAME: %s" % video.video_upload.name
  
      teacher = video.teacher
  
      print "TEACHER: %s" % teacher
  
      filename = video.video_upload
  
      sourcefile = "%s%s" % (settings.MEDIA_URL, filename)
  
      vidfilename = "%s_%s.flv" % (teacher, video.id)
  
      targetfile = "%svideos/flv/%s" % (settings.MEDIA_URL, vidfilename)
  
      ffmpeg = "ffmpeg -i %s %s" % (sourcefile, vidfilename)
  
      try:
  
          ffmpegresult = subprocess.call(ffmpeg)
  
          #also tried separately with following line:
  
          #ffmpegresult = commands.getoutput(ffmpeg)
  
          print "---------------FFMPEG---------------"
  
          print "FFMPEGRESULT: %s" % ffmpegresult
  
      except Exception as e:
  
          ffmpegresult = None
  
          print("Failed to convert video file %s to %s" % (sourcefile, targetfile))
  
          print(traceback.format_exc())
  
      video.flvfilename = vidfilename
  
      video.save()
  
  
  
  @task(name='celeryfiles.tasks.ffmpeg_image')        
  
  def ffmpeg_image(video_id):
  
      video = BroadcastUpload.objects.get(pk=video_id)
  
      print "ID: %s" %video.id
  
      id = video.id
  
      print "VIDEO NAME: %s" % video.video_upload.name
  
      teacher = video.teacher
  
      print "TEACHER: %s" % teacher
  
      filename = video.video_upload
  
      sourcefile = "%s%s" % (settings.MEDIA_URL, filename)
  
      imagefilename = "%s_%s.png" % (teacher, video.id)
  
      thumbnailfilename = "%svideos/flv/%s" % (settings.MEDIA_URL, thumbnailfilename)
  
      grabimage = "ffmpeg -y -i %s -vframes 1 -ss 00:00:02 -an -vcodec png -f rawvideo -s 320x240 %s" % (sourcefile, thumbnailfilename)
  
      try:        
  
           videothumbnail = subprocess.call(grabimage)
  
           #also tried separately following line:
  
           #videothumbnail = commands.getoutput(grabimage)
  
           print "---------------IMAGE---------------"
  
           print "VIDEOTHUMBNAIL: %s" % videothumbnail
  
      except Exception as e:
  
           videothumbnail = None
  
           print("Failed to convert video file %s to %s" % (sourcefile, thumbnailfilename))
  
           print(traceback.format_exc())
  
      video.videothumbnail = imagefilename
  
      video.save()
  
  
  
  #views.py
  
  def upload_broadcast(request):
  
      if request.method == 'POST':
  
          form = BroadcastUploadForm(request.POST, request.FILES)
  
          if form.is_valid():
  
              upload=form.save()
  
              video_id = upload.id
  
              image_grab = ffmpeg_image.delay(video_id)
  
              video_conversion = convert_flv.delay(video_id)
  
              return HttpResponseRedirect('/current_classes/')
  
      else:
  
          form = BroadcastUploadForm(initial={'teacher': request.user,})
  
      return render_to_response('videos/create_video.html', {'form': form,}, context_instance=RequestContext(request))
  
  
  
  #settings.py
  
  DEFAULT_FILE_STORAGE = 'myapp.s3utils.MediaRootS3BotoStorage'
  
  DEFAULT_S3_PATH = "media"
  
  STATICFILES_STORAGE = 'myapp.s3utils.StaticRootS3BotoStorage'
  
  STATIC_S3_PATH = "static"
  
  AWS_STORAGE_BUCKET_NAME = 'my_bucket'
  
  CLOUDFRONT_DOMAIN = 'domain.cloudfront.net'
  
  AWS_ACCESS_KEY_ID = 'MY_KEY_ID'
  
  AWS_SECRET_ACCESS_KEY = 'MY_SECRET_KEY'
  
  MEDIA_ROOT = '/%s/' % DEFAULT_S3_PATH
  
  MEDIA_URL = 'http://%s/%s/' % (CLOUDFRONT_DOMAIN, DEFAULT_S3_PATH)
  
  ...
  
  
  
  #s3utils.py
  
  from storages.backends.s3boto import S3BotoStorage
  
  from django.utils.functional import SimpleLazyObject
  
  
  
  StaticRootS3BotoStorage = lambda: S3BotoStorage(location='static')
  
  MediaRootS3BotoStorage  = lambda: S3BotoStorage(location='media')

  I can add any other info if needed to help me solve my problem.

• Configure ffmpeg for wowza and wp8

  11 octobre 2013, par Anton Shakalo

  I have mp4 file from my windows phone.

  There is info :

  General
  
  Format                                   : MPEG-4
  
  Format profile                           : Base Media / Version 2
  
  Codec ID                                 : mp42
  
  
  
  Video
  
  Format                                    : AVC
  
  Codec ID                                 : avc1
  
  Codec ID/Info                           : Advanced Video Coding
  
  
  
  Audio
  
  Format                                    : AAC
  
  Format profile                           : LC
  
  Codec ID                                 : 40
  
  Bit rate                                   : 96.0 Kbps
  
  Sampling rate                           : 44.1 KHz

  When I stream it to wowza with next ffmpeg command ( I got it from documentation)

  ffmpeg -re -i "C:\sample2.mp4"  -vcodec libx264  -vb 150000 -g 60 -vprofile main -level 2.1 -acodec aac -ab 64000 -ar 48000 -ac 2 -vbsf h264_mp4toannexb  -f mpegts udp://127.0.0.1:10001?pkt_size=1316

  In client app I see corrupted video : http://i.imgur.com/fKEMlsB.png

  With sample file provided by wowza streamed video looks fine.

  There is info about sample file from wowza :

  General
  
  Format                                   : MPEG-4
  
  Format profile                           : QuickTime
  
  Codec ID                                 : qt  
  
  
  
  Video
  
  Format                                   : AVC
  
  Format profile                           : Baseline@L3.0
  
  Codec ID                                 : avc1
  
  
  
  Audio
  
  Format                                   : AAC
  
  Format profile                           : LC
  
  Codec ID                                 : 40

  Can you help me with ffmpeg configuring ?
  I read documentation, but understand nothing.

• JavaCV FFmpegFrameRecorder properties explanation needed

  29 décembre 2014, par Leron

  I’m using FFmpegFrameRecorder to get the video input from my webcam and record it into a video file. The problem is that I’m building my application using a few different demo source codes that I found and I use properties some of which are not completely clear to me.

  First, here is my code snippet :

  FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(FILENAME,  grabber.getImageWidth(),grabber.getImageHeight());
  
  
  
          recorder.setVideoCodec(13);
  
          recorder.setFormat("mp4");
  
          recorder.setPixelFormat(avutil.PIX_FMT_YUV420P);
  
          recorder.setFrameRate(30);
  
          recorder.setVideoBitrate(10 * 1024 * 1024);
  
  
  
          recorder.start();

  • setVideoCodec(13) - What is the meaning of this (13) how can I understand what actual codec stands behind any number ?
  • setPixelFormat - Just get this, don’t know what it’s doing in general
  • setFrameRate(30) - I think this should be pretty clear but still what is the logic behind what frame rate we choose (isn’t the high the better ?)
  • setVideoBitrate(10*1024*1024) - again almost no idea what this does and what’s the logic behind the numbers ?

  At the end I just want to mention one last problem that I get recording video like this. If the actual length of the video is let’s say 20secs. When I play the video file created from the program it runs significantly faster. Can’t tell if it’s exactly 2 times faster than it should be but in general if I record a 20sec video then it’s played for about 10secs. What may cause this and how can I fix it ?