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• ffmpeg static build produces huge files

  3 mai 2014, par user3581244

  I’ve recently managed to get a static build of ffmpeg installed on an EC2 instance :

  http://ffmpeg.gusari.org/static/64bit/ffmpeg.static.64bit.2014-03-05.tar.gz

  But when I perform this command on a video file :

  ffmpeg -ss 00:00:00 -i VIDEO0031.mp4 -r 8 -vframes 32 -vbsf remove_extra -an -vcodec pam -f rawvideo -y test_002.pam

  It produces a file that is 190MB which is huge and then it messes up the other commands I use to convert it into a gif file.

  Does anyone know if this is just an issue with using a static build ? I didn’t experience this issue using an older ffmpeg install ( v0.6 I believe ) so am tempted to go back to the old install but I also need to have ffprobe installed so am worried this would cause issues.

  A bit of a random question but I thought it was worth asking just in case someone had come across a similar thing.

  Thanks !

• Segmentation Fault error when trying to compare two videos with pHash library and its ruby bindings

  10 juillet 2014, par anado1771

  I have set up my system with the latest ffmpeg and pHash libraries (ffmpeg-2.2.1 and pHash-0.9.6) as well as the pHash ruby gem (https://github.com/toy/pHash).

  I am using ruby and attempting to compare two video files like this :

  require 'phash/video'
  
  
  
  video1 = Phash::Video.new('video1.mp4')
  
  video2 = Phash::Video.new('video2.mp4')
  
  
  
  video1 % video2

  Executing this script results in a Segmentation fault :

  ..../gems/pHash-1.1.4/lib/phash/video.rb:20: [BUG] Segmentation fault
  
  ruby 1.9.3p545 (2014-02-24 revision 45159) [x86_64-darwin13.1.0]
  
  
  
  -- Control frame information -----------------------------------------------
  
  c:0008 p:---- s:0029 b:0029 l:000028 d:000028 CFUNC  :ph_dct_videohash
  
  c:0007 p:0042 s:0024 b:0024 l:000023 d:000023 METHOD .../gems/pHash-1.1.4/lib/phash/video.rb:20
  
  c:0006 p:0038 s:0017 b:0017 l:000016 d:000016 METHOD .../gems/pHash-1.1.4/lib/phash.rb:43
  
  c:0005 p:0025 s:0014 b:0014 l:000013 d:000013 METHOD .../gems/pHash-1.1.4/lib/phash.rb:39
  
  c:0004 p:0011 s:0011 b:0011 l:000010 d:000010 METHOD .../gems/pHash-1.1.4/lib/phash.rb:48
  
  c:0003 p:0050 s:0006 b:0006 l:000128 d:0011b8 EVAL   video_test_phash.rb:3
  
  c:0002 p:---- s:0004 b:0004 l:000003 d:000003 FINISH
  
  c:0001 p:0000 s:0002 b:0002 l:000128 d:000128 TOP   
  
  
  
  -- Ruby level backtrace information ----------------------------------------
  
  video_test_phash.rb:3:in `<main>'
  
  .../gems/pHash-1.1.4/lib/phash.rb:48:in `similarity'
  
  .../gems/pHash-1.1.4/lib/phash.rb:39:in `phash'
  
  .../gems/pHash-1.1.4/lib/phash.rb:43:in `compute_phash'
  
  .../gems/pHash-1.1.4/lib/phash/video.rb:20:in `video_hash'
  
  .../gems/pHash-1.1.4/lib/phash/video.rb:20:in `ph_dct_videohash'
  
  
  
  ...
  
  
  
  Abort trap: 6
  
  </main>

  It appears that the crash happens in the ph_dct_videohash function which is part of the pHash library. The function is in file pHash.cpp. I am copying it here in case it would make sense to someone :

  ulong64* ph_dct_videohash(const char *filename, int &Length){
  
  
  
      CImgList *keyframes = ph_getKeyFramesFromVideo(filename);
  
      if (keyframes == NULL)
  
      return NULL;
  
  
  
      Length = keyframes->size();
  
  
  
      ulong64 *hash = (ulong64*)malloc(sizeof(ulong64)*Length);
  
      CImg<float> *C = ph_dct_matrix(32);
  
      CImg<float> Ctransp = C->get_transpose();
  
      CImg<float> dctImage;
  
      CImg<float> subsec;
  
      CImg currentframe;
  
  
  
      for (unsigned int i=0;i &lt; keyframes->size(); i++){
  
      currentframe = keyframes->at(i);
  
      currentframe.blur(1.0);
  
      dctImage = (*C)*(currentframe)*Ctransp;
  
      subsec = dctImage.crop(1,1,8,8).unroll('x');
  
      float med = subsec.median();
  
      hash[i] =     0x0000000000000000;
  
      ulong64 one = 0x0000000000000001;
  
      for (int j=0;j&lt;64;j++){
  
          if (subsec(j) > med)
  
          hash[i] |= one;
  
          one = one &lt;&lt; 1;
  
      }
  
      }
  
  
  
      keyframes->clear();
  
      delete keyframes;
  
      keyframes = NULL;
  
      delete C;
  
      C = NULL;
  
      return hash;
  
  }
  
  </float></float></float></float>

  Any help is very much appreciated !

• Cannot concatenate videos ffmpeg [on hold]

  1er mai 2014, par Paul Prescod

  I have a bitmap that I would like to concatenate to the front of many videos as a sort of title screen or disclaimer screen.

  I try to turn it into a video with the same attributes as the rest of the video. So first I introspect the video :

  ffmpeg version 2.2.1 Copyright (c) 2000-2014 the FFmpeg developers
  
    built on Apr 11 2014 22:50:38 with Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
  
    configuration: --prefix=/usr/local/Cellar/ffmpeg/2.2.1 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables --enable-avresample --enable-vda --cc=clang --host-cflags= --host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-libxvid
  
    libavutil      52. 66.100 / 52. 66.100
  
    libavcodec     55. 52.102 / 55. 52.102
  
    libavformat    55. 33.100 / 55. 33.100
  
    libavdevice    55. 10.100 / 55. 10.100
  
    libavfilter     4.  2.100 /  4.  2.100
  
    libavresample   1.  2.  0 /  1.  2.  0
  
    libswscale      2.  5.102 /  2.  5.102
  
    libswresample   0. 18.100 /  0. 18.100
  
    libpostproc    52.  3.100 / 52.  3.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'EO1.mp4':
  
    Metadata:
  
  major_brand     : isom
  
  minor_version   : 512
  
  compatible_brands: isomiso2avc1mp41
  
  creation_time   : 1970-01-01 00:00:00
  
  encoder         : Lavf52.78.3
  
    Duration: 00:00:17.77, start: 0.000000, bitrate: 582 kb/s
  
  Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 584x328 [SAR 1:1 DAR 73:41], 512 kb/s, 23.98 fps, 23.98 tbr, 1199 tbn, 47.96 tbc (default)
  
  Metadata:
  
    creation_time   : 1970-01-01 00:00:00
  
    handler_name    : VideoHandler
  
  Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 64 kb/s (default)
  
  Metadata:
  
    creation_time   : 1970-01-01 00:00:00
  
    handler_name    : SoundHandler

  Then I try and create a similar file :

  /usr/local/Cellar/ffmpeg/2.2.1/bin/ffmpeg -y -loop 1 -i Disclaimer.png -c:v libx264 -r 23.98 -t 5 -pix_fmt yuv420p -profile:v main disclaimer.mp4

  It seems to work okay. The video plays I would expect it to. The attributes turn out very similar. Here is a diff :

  < Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'disclaimer.mp4':
  
  ---
  
  > Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'EO1.mp4':
  
  18,20c18,21
  
  <     encoder         : Lavf55.33.100
  
  <   Duration: 00:00:05.01, start: 0.000000, bitrate: 21 kb/s
  
  <     Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 584x328 [SAR 1:1 DAR 73:41], 17 kb/s, 23.98 fps, 23.98 tbr, 19184 tbn, 47.96 tbc (default)
  
  ---
  
  >     creation_time   : 1970-01-01 00:00:00
  
  >     encoder         : Lavf52.78.3
  
  >   Duration: 00:00:17.77, start: 0.000000, bitrate: 582 kb/s
  
  >     Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 584x328 [SAR 1:1 DAR 73:41], 512 kb/s, 23.98 fps, 23.98 tbr, 1199 tbn, 47.96 tbc (default)
  
  21a23
  
  22a25,28
  
  >     Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 64 kb/s (default)
  
  >     Metadata:
  
  >       handler_name    : SoundHandler

  But when I try to concatenate, I get errors.

  > $ cat temporary.txt 
  
  
  
      file disclaimer.mp4
  
      file EO1.mp4

  /usr/local/Cellar/ffmpeg/2.2.1/bin/ffmpeg -y -f concat -i temporary.txt -c copy output.mp4

  [concat @ 0x7fd880806600] Estimating duration from bitrate, this may be inaccurate
  
  Input #0, concat, from 'temporary.txt':
  
    Duration: 00:00:00.02, start: 0.000000, bitrate: 17 kb/s
  
  Stream #0:0: Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 584x328 [SAR 1:1 DAR 73:41], 17 kb/s, 23.98 fps, 23.98 tbr, 19184 tbn, 47.96 tbc
  
  Output #0, mp4, to 'output.mp4':
  
    Metadata:
  
  encoder         : Lavf55.33.100
  
  Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 584x328 [SAR 1:1 DAR 73:41], q=2-31, 17 kb/s, 23.98 fps, 19184 tbn, 19184 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (copy)
  
  Press [q] to stop, [?] for help
  
  [mp4 @ 0x7fd880829a00] Non-monotonous DTS in output stream 0:0; previous: 93600, current: 5951; changing to 93601. This may result in incorrect timestamps in the output file.
  
  [concat @ 0x7fd880806600] Invalid stream index 1
  
  [mp4 @ 0x7fd880829a00] Non-monotonous DTS in output stream 0:0; previous: 93601, current: 6001; changing to 93602. This may result in incorrect timestamps in the output file.
  
  [concat @ 0x7fd880806600] Invalid stream index 1
  
  [mp4 @ 0x7fd880829a00] Non-monotonous DTS in output stream 0:0; previous: 93602, current: 6051; changing to 93603. This may result in incorrect timestamps in the output file.

  ...

  frame=  546 fps=0.0 q=-1.0 Lsize=    1127kB time=00:00:04.90 bitrate=1882.9kbits/s    
  
  video:1123kB audio:0kB subtitle:0 data:0 global headers:0kB muxing overhead 0.349865%

  The output looks like it only has my disclaimer file in it, not the rest of the video.

  I’m also confused why it feels like it needs to "estimate" anything. It knows the input FPS and input durations. I’m not sure if this is the problem or not. Maybe its just a bug.