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• FFmpeg first frame byte size over 2x size compared to all other frames - w/ 100% keyframes

  22 juillet 2016, par Dustin Kerstein

  I’m encoding an h264 mp4 and am having a small issue with the output byte size of the first frame vs. all other frames. There’s no frame duplication happening, rather just that the first frame always ends up being 2x the byte size of other frames. My use-case requires that the first frame be very similar in size compared to other frame.

  Here are the ffmpeg encoding parameters :

  ffmpeg -framerate 60 -i "C:\Test%4d.jpg" -c:v libx264 -g 1 -vf "scale=3840:2160" -crf 19 -pix_fmt yuv420p C:\Test.mp4

  And the frame details using ffprobe :

  ffprobe C:\Test.mp4 -show_frames -of compact -show_entries frame=pict_type,pkt_size
  
  
  
  ffprobe version N-79143-g8ff0f6a Copyright (c) 2007-2016 the FFmpeg developers
  
    built with gcc 5.3.0 (GCC)
  
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmfx --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --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-decklink --enable-zlib
  
    libavutil      55. 19.100 / 55. 19.100
  
    libavcodec     57. 30.100 / 57. 30.100
  
    libavformat    57. 29.101 / 57. 29.101
  
    libavdevice    57.  0.101 / 57.  0.101
  
    libavfilter     6. 40.102 /  6. 40.102
  
    libswscale      4.  0.100 /  4.  0.100
  
    libswresample   2.  0.101 /  2.  0.101
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'C:\users\dusti\downloads\Test.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.29.101
  
    Duration: 00:00:00.17, start: 0.000000, bitrate: 240225 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 3840x2160 [SAR 9:16 DAR 1:1], 240662 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
  frame|pkt_size=1377043|pict_type=I
  
  frame|pkt_size=406953|pict_type=I
  
  frame|pkt_size=407200|pict_type=I
  
  frame|pkt_size=406647|pict_type=I
  
  frame|pkt_size=405276|pict_type=I
  
  frame|pkt_size=404715|pict_type=I
  
  frame|pkt_size=403226|pict_type=I
  
  frame|pkt_size=401806|pict_type=I
  
  frame|pkt_size=400750|pict_type=I
  
  frame|pkt_size=400189|pict_type=I

  I’ve confirmed that it’s not just a reporting issue with ffprobe by converting the file with mp4box :

  mp4box.exe -dash 16.666 -frag 16.666 -rap c:\Test.mp4

  Which returns an MPD file :

  <initialization range="0-922"></initialization>
  
        <segmenturl mediarange="923-1378146" indexrange="923-966"></segmenturl>
  
        <segmenturl mediarange="1378147-1785280" indexrange="1378147-1378190"></segmenturl>
  
        <segmenturl mediarange="1785281-2192661" indexrange="1785281-1785324"></segmenturl>
  
        <segmenturl mediarange="2192662-2599489" indexrange="2192662-2192705"></segmenturl>
  
        <segmenturl mediarange="2599490-3004946" indexrange="2599490-2599533"></segmenturl>
  
        <segmenturl mediarange="3004947-3409842" indexrange="3004947-3004990"></segmenturl>
  
        <segmenturl mediarange="3409843-3813249" indexrange="3409843-3409886"></segmenturl>
  
        <segmenturl mediarange="3813250-4215236" indexrange="3813250-3813293"></segmenturl>
  
        <segmenturl mediarange="4215237-4616167" indexrange="4215237-4215280"></segmenturl>
  
        <segmenturl mediarange="4616168-5016537" indexrange="4616168-4616211"></segmenturl>
  
      

  I tried encoding a dummy black frame and it does seem to work around the issue but I’d really prefer to not do that. Here are the frame sizes with the first frame replaced by a pure black frame :

  frame|pkt_size=2173|pict_type=I
  
  frame|pkt_size=466255|pict_type=I
  
  frame|pkt_size=430179|pict_type=I
  
  frame|pkt_size=416652|pict_type=I
  
  frame|pkt_size=411401|pict_type=I
  
  frame|pkt_size=407174|pict_type=I
  
  frame|pkt_size=405377|pict_type=I
  
  frame|pkt_size=403207|pict_type=I
  
  frame|pkt_size=401588|pict_type=I
  
  frame|pkt_size=401200|pict_type=I

  Anyone have any clues on how to control this behavior ? I imagine it might have something to do with the CRF quality algorithm but really have no idea. Any help would be appreciated.

  Thanks,
  Dustin

  Update 7/22/16
  Upon a little more digging I can see that ffmpeg is using a lower QP for the first frame :

  [libx264 @ 05380b60] frame=   0 QP=14.92 NAL=3 Slice:I Poc:0   I:32400 P:0    SKIP:0    size=1485053 bytes
  
  [libx264 @ 05380b60] frame=   1 QP=29.48 NAL=3 Slice:I Poc:0   I:32400 P:0    SKIP:0    size=361196 bytes
  
  [libx264 @ 05380b60] frame=   2 QP=29.48 NAL=3 Slice:I Poc:0   I:32400 P:0    SKIP:0    size=359406 bytes

  But I’ve still not found a way to avoid this behavior. I tried setting qpmin/qpmax to non-default values but that didn’t change anything. Per my comment below, two-pass encoding does not exhibit this behavior. Still looking for a way to use CRF encoding without this large initial frame.

• avfoundation error. Cannot detect list_devices

  12 septembre 2016, par xiaose

  I need to get ID for current screen and, as it said here, I tried to get list of all available input devices...

  Whith command ffmpeg -f avfoundation -list_devices true -i ''

  It works fine on two my Mac but on the third, with OSX 10.7.5 it does not works :

  $ ./ffmpeg -f avfoundation -list_devices true -i ''
  
  ffmpeg version 3.1.1 Copyright (c) 2000-2016 the FFmpeg developers
  
  ...
  
  Unrecognized option 'list_devices'.

  I got

  Unrecognized option ’list_devices’

  there and don’t know how to fix it. Could you help me with that ?

  Like I understand this situation, there is issue with avfoundation. It just doesn’t works correctly...

  From another side it gives me error :

  Unknown format ’avfoundation’

  $ ./ffmpeg -h demuxer=avfoundation
  
  ffmpeg version 3.1.1 Copyright (c) 2000-2016 the FFmpeg developers
  
  ...
  
  Unknown format 'avfoundation'.

  UPD : issue was in ffmpeg. That version what I used just does not support interaction with avfoundation

• ffmpeg No such filter : 'palettegen' in linux

  29 juillet 2016, par royise

  1.

  my system 
  
  uname -a
  
  Linux localhost.localdomain 2.6.32-220.el6.x86_64 #1 SMP Tue Dec 6 19:48:22 GMT 2011 x86_64 x86_64 x86_64 GNU/Linux

  2.ffmpeg is download from
  http://johnvansickle.com/ffmpeg/

  3.I had download the ffmpeg-release-64bit-static.tar.xz ,unpackage this file, and run : ./ffmpeg
  then ffmpeg has installed. I check it by using : ffmpeg -version
  no problems.

  I run those command in my system is no problem :
  

  cd /home/web/tomcat-6.0.29/zhouletest/ffmpeg-3.1.1-64bit-static 
  
  
  
  ./ffmpeg -y -ss 10 -t 3 -i /home/web/tomcat-6.0.29/zhouletest/videos/6.mp4 -vf fps=10,scale=177:-1:flags=lanczos,palettegen /home/web/tomcat-6.0.29/zhouletest/gif_images/palettegens/6.png 
  
  
  
  ./ffmpeg -y -ss 10 -t 3 -i /home/web/tomcat-6.0.29/zhouletest/videos/6.mp4 -i /home/web/tomcat-6.0.29/zhouletest/gif_images/palettegens/6.png -filter_complex "fps=10,scale=177:-1:flags=lanczos[x];[x][1:v]paletteuse" /home/web/tomcat-6.0.29/zhouletest/gif_images/6.gif

  but when I invoke this command in java, errors happend, why ?
  

  String cmd1 = "/home/web/tomcat-6.0.29/zhouletest/ffmpeg -y -ss 10 -t 3 -i /home/web/tomcat-6.0.29/zhouletest/videos/6.mp4 -vf fps=10,scale=177:-1:flags=lanczos,palettegen /home/web/tomcat-6.0.29/zhouletest/gif_images/palettegens/6.png";
  
  String cmd2 = "/home/web/tomcat-6.0.29/zhouletest/ffmpeg-3.1.1-64bit-static/ffmpeg -y -ss 10 -t 3 -i /home/web/tomcat-6.0.29/zhouletest/videos/6.mp4 -i /home/web/tomcat-6.0.29/zhouletest/gif_images/palettegens/6.png -filter_complex \"fps=10,scale=177:-1:flags=lanczos[x];[x][1:v]paletteuse\" /home/web/tomcat-6.0.29/zhouletest/gif_images/6.gif";
  
  
  
  String result1 = executeCommand(cmd1);
  
  String result2 = executeCommand(cmd2);
  
  
  
  private static String executeCommand(String command) {
  
      StringBuffer output = new StringBuffer();
  
      Process p;
  
      try {
  
          p = Runtime.getRuntime().exec(command);
  
          p.waitFor();
  
          BufferedReader reader = new BufferedReader(new InputStreamReader(p.getErrorStream()));
  
  
  
          String line = "";
  
          while ((line = reader.readLine())!= null) {
  
              output.append(line + "\n");
  
          }
  
  
  
      } catch (Exception e) {
  
          e.printStackTrace();
  
      }
  
      return output.toString();
  
  }

  errors :

  result1 :
  result2:ffmpeg version 3.1.1-static
  http://johnvansickle.com/ffmpeg/ Copyright (c) 2000-2016 the FFmpeg
  developers
  built with gcc 5.4.0 (Debian 5.4.0-4) 20160609
  configuration : —enable-gpl —enable-version3 —enable-static
  —disable-debug —enable-libmp3lame —enable-libx264 —enable-libx265 —enable-libwebp —enable-libspeex —enable-libvorbis —enable-libvpx —enable-libfreetype —enable-fontconfig —enable-libxvid —enable-libopencore-amrnb —enable-libopencore-amrwb —enable-libtheora —enable-libvo-amrwbenc —enable-gray —enable-libopenjpeg —enable-libopus —enable-libass —enable-gnutls —enable-libvidstab —enable-libsoxr —enable-frei0r —enable-libfribidi —disable-indev=sndio —disable-outdev=sndio —enable-librtmp —enable-libmfx —enable-libzimg —cc=gcc
  libavutil 55. 28.100 / 55. 28.100
  libavcodec 57.
  48.101 / 57. 48.101
  libavformat 57. 41.100 / 57. 41.100
  libavdevice 57. 0.101 / 57. 0.101
  libavfilter
  6. 47.100 / 6. 47.100
  libswscale 4. 1.100 / 4. 1.100
  libswresample 2. 1.100 / 2. 1.100
  libpostproc
  54. 0.100 / 54. 0.100
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ’/home/web/tomcat-6.0.29/zhouletest/videos/6.mp4’ :
  Metadata :
  
  major_brand : isom
  minor_version : 512
  compatible_brands : isomiso2avc1mp41
  encoder : Lavf56.40.101
  Duration : 00:04:36.64, start : -3.338000, bitrate : 1089 kb/s
  Stream #0:0(und) : Video : h264 (Main) (avc1 / 0x31637661), yuv420p, 480x360, 997 kb/s, 15 fps, 15 tbr, 16k tbn, 30 tbc (default)
  Metadata :
  handler_name : VideoHandler
  Stream #0:1(und) : Audio : aac (Main) (mp4a / 0x6134706D), 22050 Hz, stereo, fltp, 88 kb/s (default)
  Metadata :
  handler_name : SoundHandler
  Input #1, png_pipe, from ’/home/web/tomcat-6.0.29/zhouletest/gif_images/palettegens/6.png’ :
  
  Duration : N/A, bitrate : N/A
  Stream #1:0 : Video : png, rgba(pc), 16x16 [SAR 1:1 DAR 1:1], 25 tbr, 25 tbn, 25 tbc
  [AVFilterGraph @ 0x45c5260] No such filter :
  ’"fps’
  Error initializing complex filters.
  Invalid
  argument