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• JW Player can't play mp4 video downloaded from youtube

  20 janvier 2015, par kheya

  I have doenloaded am mp4 video using IE Realplayer plugin from youtube.
  https://www.youtube.com/watch?v=e3a80c5Ar3Y

  I have a test site on my local machine where I have HTML5 JW Player.

  I download the video and then play locally using realplay to see if it plays.
  I notice that not all mp4 downloads from youtube plays in Realplayer.
  The ones that play in Realplayer also play in JW Player on local website.
  But the mp4 files that don’t play in Realplayer also don’t play in JW player.

  This is the error I get in the player :
  the video playback was aborted due to a corruption problem or because the video used features your browser didnot support mylocalsite/xyz.mp4 undefined

  I tested IE, FF, Chrome. It works nowhere.

  Here is my jw player setup and html :

  <video src="mylocalsite/test.mp4" type="video/mp4" poster="mylocalsite/test.jpg" width="640" height="360"></video>

  player setup :

  var modes = '';
  
  var swfPath = '/content/jw/player.swf';
  
              if (navigator.userAgent.toLowerCase().match(/(android)/) || navigator.userAgent.toLowerCase().match(/(chrom)/)) {                
  
                  modes = [{ type: 'flash', src: swfPath }, { type: "html5"}];
  
              } else {
  
                  modes = [{ type: 'html5' }, { type: 'flash', src: swfPath }, { type: "download"}];
  
              }
  
  
  
  jwplayer('container').setup({                
  
                  'flashplayer': swfPath,                
  
                  'width': '640',
  
                  'height': '360',
  
                  'provider': 'video',
  
                  'modes': modes,                
  
              });

  Here is the details info about the file returned by ffmpeg :

  ffmpeg version 1.1.4 Copyright (c) 2000-2013 the FFmpeg developers
  
    built on Jul 31 2013 02:49:36 with gcc 4.6.2 (GCC)
  
    configuration: --prefix=/c/Users/Administrator/ffmpeg --extra-cflags=-I/c/User
  
  s/Administrator/ffmpeg/include --extra-ldflags=-L/c/Users/Administrator/ffmpeg/l
  
  ib --cpu=i686 --enable-gpl --enable-libfdk-aac --enable-libx264 --enable-nonfree
  
  
  
    libavutil      52. 13.100 / 52. 13.100
  
    libavcodec     54. 86.100 / 54. 86.100
  
    libavformat    54. 59.106 / 54. 59.106
  
    libavdevice    54.  3.102 / 54.  3.102
  
    libavfilter     3. 32.100 /  3. 32.100
  
    libswscale      2.  1.103 /  2.  1.103
  
    libswresample   0. 17.102 /  0. 17.102
  
    libpostproc    52.  2.100 / 52.  2.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'C:\videos\woh.mp4':
  
    Metadata:
  
      major_brand     : dash
  
      minor_version   : 0
  
      compatible_brands: iso6avc1mp41
  
      creation_time   : 2013-09-08 23:34:28
  
    Duration: 00:03:50.96, start: 0.000000, bitrate: 189 kb/s
  
      Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 480x360,
  
  187 kb/s, 25 tbr, 90k tbn, 50 tbc
  
      Metadata:
  
        creation_time   : 2013-09-08 23:34:28
  
        handler_name    : VideoHandler

  What can be causing this issue ?

• Compressing videos from a smartphone

  21 septembre 2019, par fejesjoco

  I have a Nexus 6p with the stock camera. It’s set to record at 1080p, 30fps. Here’s a 5 second sample (11 MB).

  Videos from this phone come out at about 17 Mbps on average. I tried to compress it with ffmpeg with -c:v libx264 -crf 23 -preset veryslow, the result comes out at about 5.5 MB, which is about 9 Mbps.

  I think this bitrate is a bit too much. When I look at torrent file listings, I can see high quality videos at 3 GB in size on average, and if such a movie is 90 minutes long on average, that is about 4-5 Mbps which sounds okay.

  I’m wondering, why the big difference ? I can notice that my video is noisy/grainy (which is expected from a phone), and that might reduce compressibility. I tried a few ffmpeg filters, like hqdn3d and atadenoise, but the noise mostly remained (maybe I didn’t play with it enough). Then I figured, the video is also shaky (which is also expected), and that might reduce compressibility too (and even makes temporal noise filtering less effective). I tried to stabilize it with the deshake filter, but that didn’t help either.

  I know I could just limit the bandwidth to whatever I like, but there must be a reason why ffmpeg thinks it needs a high bandwidth to maintain a certain quality, and a lower bandwidth would just decrease the quality.

  Why do these videos have such a high bitrate ? What’s the best way to compress them more while keeping or even increasing their quality ?

• Compressing videos from a smartphone

  9 novembre 2016, par fejesjoco

  I have a Nexus 6p with the stock camera. It’s set to record at 1080p, 30fps. Here’s a 5 second sample (11 MB).

  Videos from this phone come out at about 17 Mbps on average. I tried to compress it with ffmpeg with -c:v libx264 -crf 23 -preset veryslow, the result comes out at about 5.5 MB, which is about 9 Mbps.

  I think this bitrate is a bit too much. When I look at torrent file listings, I can see high quality videos at 3 GB in size on average, and if such a movie is 90 minutes long on average, that is about 4-5 Mbps which sounds okay.

  I’m wondering, why the big difference ? I can notice that my video is noisy/grainy (which is expected from a phone), and that might reduce compressibility. I tried a few ffmpeg filters, like hqdn3d and atadenoise, but the noise mostly remained (maybe I didn’t play with it enough). Then I figured, the video is also shaky (which is also expected), and that might reduce compressibility too (and even makes temporal noise filtering less effective). I tried to stabilize it with the deshake filter, but that didn’t help either.

  I know I could just limit the bandwidth to whatever I like, but there must be a reason why ffmpeg thinks it needs a high bandwidth to maintain a certain quality, and a lower bandwidth would just decrease the quality.

  Why do these videos have such a high bitrate ? What’s the best way to compress them more while keeping or even increasing their quality ?