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• Why Recode Video FFMPEG on windows Allway Error ?

  9 janvier 2012, par ALexF

  i download ffmpeg in : http://ramiro.arrozcru.org/ffmpeg-vfwcap-noflip.7z

  and run it with commanline : ffmpeg -r 25 -f vfwcap -i 0 output.avi

  but allway error is

  ffmpeg -r 25 -f vfwcap -i 0 output.avi
  FFmpeg version SVN-r22915, Copyright (c) 2000-2010 the FFmpeg developers
  built on Apr 20 2010 00:09:08 with gcc 4.4.2
  configuration : —enable-memalign-hack —cross-prefix=i686-mingw32- —cc=ccach
   i686-mingw32-gcc —arch=i686 —target-os=mingw32 —enable-gpl —enable-libx264
  — enable-pthreads
  libavutil 50.14. 0 / 50.14. 0
  libavcodec 52.66. 0 / 52.66. 0
  libavformat 52.61. 0 / 52.61. 0
  libavdevice 52. 2. 0 / 52. 2. 0
  libswscale 0.10. 0 / 0.10. 0
  [vfwcap @ 012eba60]Could not connect to device.
  0 : Error number -19 occurred

  Link Image :http://nh8.upanh.com/b2.s8.d2/9b09371490590cdabef397ea7705b304_39810848.programmanager20120109110016.png

  why it error, can you fix my commnaline

• Cannot play this video when converting format to .mp4

  22 décembre 2015, par user3653474

  I am converting video to .mp4 format, but when i convert video using ffmpeg using the following command :

  exec('D:\wamp\bin\ffmpeg.exe -y -i D:/wamp/www/upload_google_drive/output.flv -c:v libx264 -crf 19 -preset slow -c:a aac -strict experimental -b:a 192k -ac 2 D:/wamp/www/upload_google_drive/w3.mp4 2>&1',$output);

  in some of the devices it does not run. The message which appears is

  Cannot play this video.

  Please help to sort out my issue.

  Output :

       Array ( [0] => ffmpeg version N-77137-gff6dd58 Copyright (c) 2000-2015 the FFmpeg developers [1] => built with gcc 5.2.0 (GCC) 
  
      [2] => 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-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --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 
  
      [3] => libavutil 55. 10.100 / 55. 10.100 
  
      [4] => libavcodec 57. 17.100 / 57. 17.100 
  
      [5] => libavformat 57. 19.100 / 57. 19.100 
  
      [6] => libavdevice 57. 0.100 / 57. 0.100 
  
      [7] => libavfilter 6. 20.100 / 6. 20.100 
  
      [8] => libswscale 4. 0.100 / 4. 0.100 
  
      [9] => libswresample 2. 0.101 / 2. 0.101 
  
      [10] => libpostproc 54. 0.100 / 54. 0.100 
  
      [11] => Input #0, flv, from 'D:/wamp/www/upload_google_drive/output.flv': 
  
      [12] => Metadata: 
  
      [13] => major_brand : mp42 
  
      [14] => minor_version : 1 
  
      [15] => compatible_brands: mp42avc1 
  
      [16] => encoder : Lavf57.19.100 
  
      [17] => Duration: 00:01:00.14, start: 0.000000, bitrate: 307 kb/s 
  
      [18] => Stream #0:0: Video: flv1, yuv420p, 480x320, 200 kb/s, 24 fps, 24 tbr, 1k tbn, 1k tbc 
  
      [19] => Stream #0:1: Audio: aac (LC), 44100 Hz, mono, fltp, 62 kb/s 
  
      [20] => [libx264 @ 0000000001c31860] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 
  
  
  
  [21] => [libx264 @ 0000000001c31860] profile Constrained Baseline, level 3.0 [22] => [libx264 @ 0000000001c31860] 264 - core 148 r2638 7599210 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=0 ref=5 deblock=1:0:0 analyse=0x1:0x111 me=umh subme=8 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=24 scenecut=40 intra_refresh=0 rc_lookahead=50 rc=crf mbtree=1 crf=19.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00 
  
  [23] => Output #0, mp4, to 'D:/wamp/www/upload_google_drive/w5.mp4': 
  
  [24] => Metadata: 
  
  [25] => major_brand : mp42 
  
  [26] => minor_version : 1 
  
  [27] => compatible_brands: mp42avc1 
  
  [28] => encoder : Lavf57.19.100 
  
  [29] => Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 480x320, q=-1--1, 24 fps, 12288 tbn, 24 tbc 
  
  [30] => Metadata: 
  
  [31] => encoder : Lavc57.17.100 libx264 
  
  [32] => Stream #0:1: Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, fltp, 192 kb/s 
  
  [33] => Metadata: 
  
  [34] => encoder : Lavc57.17.100 aac 
  
  [35] => Stream mapping: 
  
  [36] => Stream #0:0 -> #0:0 (flv1 (flv) -> h264 (libx264)) 
  
  [37] => Stream #0:1 -> #0:1 (aac (native) -> aac (native)) 
  
  [38] => Press [q] to stop, [?] for help 
  
  [39] => frame= 55 fps=0.0 q=23.0 size= 27kB time=00:00:02.22 bitrate= 98.2kbits/s frame= 96 fps= 93 q=24.0 size= 137kB time=00:00:03.92 bitrate= 285.4kbits/s frame= 161 fps=105 q=24.0 size= 317kB time=00:00:06.64 bitrate= 391.6kbits/s frame= 220 fps=108 q=24.0 size= 541kB time=00:00:09.07 bitrate= 487.8kbits/s frame= 274 fps=108 q=24.0 size= 773kB time=00:00:11.35 bitrate= 557.8kbits/s frame= 326 fps=107 q=24.0 size= 1109kB time=00:00:13.53 bitrate= 671.4kbits/s Past duration 0.607994 too large 
  
  [40] => Last message repeated 1 times 
  
  [41] => Past duration 0.615990 too large 
  
  [42] => Past duration 0.607994 too large 
  
  [43] => frame= 382 fps=108 q=24.0 size= 1439kB time=00:00:15.81 bitrate= 745.6kbits/s Past duration 0.615990 too large 
  
  [44] => Past duration 0.607994 too large 
  
  [45] => Past duration 0.623985 too large 
  
  [46] => Past duration 0.615990 too large 
  
  [47] => Past duration 0.607994 too large
  
  [48] => Past duration 0.623985 too large 
  
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  [50] => Past duration 0.631996 too large 
  
  [51] => Past duration 0.623985 too large 
  
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  [55] => Past duration 0.639992 too large
  
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  [74] => Past duration 0.655998 too large 
  
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  [77] => Past duration 0.655998 too large 
  
  [78] => Past duration 0.671989 too large 
  
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  [88] => Past duration 0.687996 too large 
  
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  [95] => Past duration 0.703987 too large 
  
  [96] => Past duration 0.695992 too large 
  
  [97] => frame= 436 fps=108 q=24.0 size= 1732kB time=00:00:18.08 bitrate= 784.5kbits/s Past duration 0.687996 too large 
  
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  [144] => Past duration 0.767998 too large 
  
  [145] => Past duration 0.783989 too large 
  
  [146] => Past duration 0.775993 too large 
  
  [147] => Past duration 0.767998 too large 
  
  [148] => Past duration 0.783989 too large 
  
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  [152] => Past duration 0.775993 too large 
  
  [153] => Past duration 0.792000 too large 
  
  [154] => Past duration 0.783989 too large 
  
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  [157] => Past duration 0.783989 too large 
  
  [158] => Past duration 0.799995 too large 
  
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  [161] => Past duration 0.799995 too large 
  
  [162] => Past duration 0.792000 too large 
  
  [163] => Past duration 0.807991 too large 
  
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  [166] => Past duration 0.807991 too large 
  
  [167] => Past duration 0.799995 too large 
  
  [168] => Past duration 0.815987 too large 
  
  [169] => frame= 508 fps=112 q=24.0 size= 1953kB time=00:00:21.10 bitrate= 758.1kbits/s Past duration 0.807991 too large 
  
  [170] => Past duration 0.823997 too large 
  
  [171] => Past duration 0.815987 too large 
  
  [172] => Past duration 0.807991 too large 
  
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  [229] => Past duration 0.903999 too large 
  
  [230] => Past duration 0.919991 too large 
  
  [231] => Past duration 0.911995 too large 
  
  [232] => frame= 571 fps=113 q=24.0 size= 2150kB time=00:00:23.68 bitrate= 743.7kbits/s Past duration 0.903999 too large 
  
  [233] => Past duration 0.919991 too large 
  
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  [246] => Past duration 0.935997 too large 
  
  [247] => Past duration 0.927986 too large 
  
  [248] => Past duration 0.943993 too large 
  
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  [251] => Past duration 0.943993 too large 
  
  [252] => Past duration 0.935997 too large 
  
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  [254] => Past duration 0.943993 too large 
  
  [255] => Past duration 0.959999 too large 
  
  [256] => Past duration 0.951988 too large 
  
  [257] => Past duration 0.943993 too large 
  
  [258] => Past duration 0.959999 too large 
  
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  [260] => Past duration 0.967995 too large 
  
  [261] => Past duration 0.959999 too large 
  
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  [263] => Past duration 0.967995 too large 
  
  [264] => Past duration 0.959999 too large 
  
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  [266] => Past duration 0.967995 too large 
  
  [267] => Past duration 0.959999 too large 
  
  [268] => Past duration 0.975990 too large 
  
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  [270] => Past duration 0.983986 too large 
  
  [271] => Past duration 0.975990 too large 
  
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  [276] => Past duration 0.983986 too large 
  
  [277] => Past duration 0.975990 too large 
  
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  [280] => Past duration 0.999992 too large 
  
  [281] => Past duration 0.991997 too large 
  
  [282] => Past duration 0.983986 too large 
  
  [283] => frame= 622 fps=112 q=24.0 size= 2328kB time=00:00:25.82 bitrate= 738.7kbits/s Past duration 0.999992 too large 
  
  [284] => Past duration 0.991997 too large 
  
  [285] => Past duration 0.999992 too large 
  
  [286] => Past duration 0.991997 too large 
  
  [287] => Past duration 0.999992 too large 
  
  [288] => Last message repeated 1 times 
  
  [289] => frame= 672 fps=111 q=24.0 size= 2585kB time=00:00:27.91 bitrate= 758.8kbits/s frame= 719 fps=110 q=24.0 size= 2829kB time=00:00:29.86 bitrate= 776.0kbits/s frame= 765 fps=109 q=24.0 size= 3063kB time=00:00:31.76 bitrate= 789.8kbits/s frame= 812 fps=108 q=24.0 size= 3282kB time=00:00:33.71 bitrate= 797.5kbits/s frame= 853 fps=106 q=24.0 size= 3472kB time=00:00:35.45 bitrate= 802.2kbits/s frame= 897 fps=105 q=24.0 size= 3713kB time=00:00:37.26 bitrate= 816.1kbits/s frame= 943 fps=104 q=24.0 size= 3960kB time=00:00:39.17 bitrate= 828.0kbits/s frame= 987 fps=103 q=24.0 size= 4205kB time=00:00:41.00 bitrate= 840.1kbits/s frame= 1033 fps=102 q=24.0 size= 4442kB time=00:00:42.91 bitrate= 848.1kbits/s frame= 1074 fps=101 q=24.0 size= 4627kB time=00:00:44.60 bitrate= 849.7kbits/s frame= 1123 fps=101 q=24.0 size= 4861kB time=00:00:46.67 bitrate= 853.3kbits/s frame= 1168 fps=101 q=24.0 size= 5079kB time=00:00:48.52 bitrate= 857.3kbits/s frame= 1216 fps=100 q=24.0 size= 5312kB time=00:00:50.52 bitrate= 861.3kbits/s frame= 1254 fps= 99 q=24.0 size= 5519kB time=00:00:52.10 bitrate= 867.7kbits/s frame= 1302 fps= 99 q=24.0 size= 5751kB time=00:00:54.12 bitrate= 870.5kbits/s frame= 1358 fps= 99 q=24.0 size= 6002kB time=00:00:56.47 bitrate= 870.8kbits/s dup=0 drop=1 frame= 1427 fps=101 q=24.0 size= 6243kB time=00:00:59.35 bitrate= 861.8kbits/s dup=0 drop=1 frame= 1444 fps=100 q=-1.0 Lsize= 6451kB time=00:01:00.16 bitrate= 878.3kbits/s dup=0 drop=1 
  
  [290] => video:5008kB audio:1407kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.550038% 
  
  [291] => [libx264 @ 0000000001c31860] frame I:10 Avg QP:13.67 size: 25967 
  
  [292] => [libx264 @ 0000000001c31860] frame P:1434 Avg QP:18.73 size: 3395 
  
  [293] => [libx264 @ 0000000001c31860] mb I I16..4: 36.0% 0.0% 64.0% 
  
  [294] => [libx264 @ 0000000001c31860] mb P I16..4: 3.6% 0.0% 4.0% P16..4: 21.9% 5.5% 4.2% 0.0% 0.0% skip:60.8% 
  
  [295] => [libx264 @ 0000000001c31860] coded y,uvDC,uvAC intra: 51.3% 62.1% 11.5% inter: 11.4% 14.4% 2.1% 
  
  [296] => [libx264 @ 0000000001c31860] i16 v,h,dc,p: 52% 30% 16% 2% 
  
  [297] => [libx264 @ 0000000001c31860] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 34% 25% 17% 3% 4% 4% 3% 4% 5% 
  
  [298] => [libx264 @ 0000000001c31860] i8c dc,h,v,p: 39% 32% 25% 4% 
  
  [299] => [libx264 @ 0000000001c31860] ref P L0: 82.2% 8.5% 4.8% 2.2% 2.3% 
  
  [300] => [libx264 @ 0000000001c31860] kb/s:681.85 [301] => [aac @ 0000000001c322a0] Qavg: 14325.964 )

• Video frame difference with FFMPEG

  27 décembre 2015, par StepTNT

  I need to compute the frame differences between a source video and a compressed one.
  For now I’m using OpenCV with Java, by extracting each frame and doing a simple difference, but it’s quite slow (working a 0.5 fps, meaning that a 500 frames video will take more than 15 mins) so I was thinking to move to FFMPEG.

  FFMPEG feels a lot faster (everything’s done under 1 minute) but it has one big issue that makes the results useless : when compressing the source file, done with FFMPEG too, an extra gray frame is added at the beginning and this fakes the results because different frames are compared.

  This is what I’m doing now (knowing that the extra frame messes it all) :

  ffmpeg -y -i src.avi -i compressed.avi -filter_complex "blend=all_mode=difference,hue=s=0" -c:v libx264 -crf 18 -c:a copy difference.avi

  To fix the frame issue I was trying to remove the first frame by re-encoding the compressed video with this command

  ffmpeg -y -ss 0.02 -i compressed.mpg -an -f mpeg2video compressed-cut.mpg"

  (Note that -ss is 0.02 because it’s a 50 fps video, so I did 1/FPS as suggested here)

  But I get this response

  Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)

  So, finally, the question is : since extracting all the frames and then compute differences with OpenCV is really slow, how can I use FFMPEG to produce a video containing the difference between two sources while keeping in mind that one of them has an extra frame at the beginning ?

  EDIT : I wanted to avoid posting endless console outputs but since you asked for it, here we go.

  1) Encoding

  Input

  ffmpeg -i "720p50_mobcal_ter.avi" -an -f mpeg2video -y "720p50_mobcal_ter.mpg"

  Output

  ffmpeg version N-76684-g1fe82ab Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 5.2.0 (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-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --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.  6.100 / 55.  6.100
  
    libavcodec     57. 15.100 / 57. 15.100
  
    libavformat    57. 14.100 / 57. 14.100
  
    libavdevice    57.  0.100 / 57.  0.100
  
    libavfilter     6. 15.100 /  6. 15.100
  
    libswscale      4.  0.100 /  4.  0.100
  
    libswresample   2.  0.101 /  2.  0.101
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Input #0, avi, from '720p50_mobcal_ter.avi':
  
    Metadata:
  
      encoder         : Lavf57.14.100
  
    Duration: 00:00:10.08, start: 0.000000, bitrate: 552974 kb/s
  
      Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1280x720, 554059 kb/s, SAR 1:1 DAR 16:9, 50 fps, 50 tbr, 50 tbn, 50 tbc
  
  Output #0, mpeg2video, to '720p50_mobcal_ter.mpg':
  
    Metadata:
  
      encoder         : Lavf57.14.100
  
      Stream #0:0: Video: mpeg2video, yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 50 fps, 50 tbn, 50 tbc
  
      Metadata:
  
        encoder         : Lavc57.15.100 mpeg2video
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> mpeg2video (native))
  
  Press [q] to stop, [?] for help
  
  frame=   41 fps=0.0 q=31.0 size=     984kB time=00:00:00.78 bitrate=10330.5kbits/frame=   80 fps= 78 q=31.0 size=    1323kB time=00:00:01.56 bitrate=6948.1kbits/frame=  124 fps= 80 q=31.0 size=    1725kB time=00:00:02.44 bitrate=5790.0kbits/frame=  168 fps= 81 q=31.0 size=    2084kB time=00:00:03.32 bitrate=5142.8kbits/frame=  212 fps= 81 q=31.0 size=    2482kB time=00:00:04.20 bitrate=4841.4kbits/frame=  255 fps= 82 q=31.0 size=    2840kB time=00:00:05.06 bitrate=4597.2kbits/frame=  296 fps= 82 q=31.0 size=    3133kB time=00:00:05.88 bitrate=4364.5kbits/frame=  338 fps= 82 q=24.8 size=    3453kB time=00:00:06.72 bitrate=4209.2kbits/frame=  382 fps= 82 q=31.0 size=    3723kB time=00:00:07.60 bitrate=4013.4kbits/frame=  426 fps= 83 q=31.0 size=    4005kB time=00:00:08.48 bitrate=3869.1kbits/frame=  470 fps= 83 q=24.8 size=    4276kB time=00:00:09.36 bitrate=3742.5kbits/frame=  504 fps= 83 q=31.0 Lsize=    4469kB time=00:00:10.06 bitrate=3639.3kbits/s
  
  video:4469kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%

  This adds the extra grey frame at the beginning, it just duplicates the first one

  2) Removing first frame

  Input

  ffmpeg -y -i "720p50_mobcal_ter.mpg" -an -f mpeg2video -vf select=gte(n\,1) "CUT-720p50_mobcal_ter.mpg"

  Output

  ffmpeg version N-76684-g1fe82ab Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 5.2.0 (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-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --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.  6.100 / 55.  6.100
  
    libavcodec     57. 15.100 / 57. 15.100
  
    libavformat    57. 14.100 / 57. 14.100
  
    libavdevice    57.  0.100 / 57.  0.100
  
    libavfilter     6. 15.100 /  6. 15.100
  
    libswscale      4.  0.100 /  4.  0.100
  
    libswresample   2.  0.101 /  2.  0.101
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Input #0, mpegvideo, from '720p50_mobcal_ter.mpg':
  
    Duration: N/A, bitrate: N/A
  
      Stream #0:0: Video: mpeg2video (Main), yuv420p(tv), 1280x720 [SAR 1:1 DAR 16:9], max. 104857 kb/s, 50 fps, 50 tbr, 1200k tbn, 100 tbc
  
  Output #0, mpeg2video, to 'CUT-720p50_mobcal_ter.mpg':
  
    Metadata:
  
      encoder         : Lavf57.14.100
  
      Stream #0:0: Video: mpeg2video, yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 50 fps, 50 tbn, 50 tbc
  
      Metadata:
  
        encoder         : Lavc57.15.100 mpeg2video
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (mpeg2video (native) -> mpeg2video (native))
  
  Press [q] to stop, [?] for help
  
  frame=  255 fps=0.0 q=31.0 size=    2781kB time=00:00:05.10 bitrate=4467.3kbits/frame=  503 fps=0.0 q=31.0 Lsize=    4415kB time=00:00:10.08 bitrate=3588.5kbits/s
  
  video:4415kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%

  3) Frame difference

  Input

  ffmpeg -y -i "720p50_mobcal_ter.avi" -i "CUT-720p50_mobcal_ter.mpg" -filter_complex "blend=all_mode=difference,hue=s=0" -c:v libx264 -crf 18 -c:a copy "DIFF-720p50_mobcal_ter.mpg"

  Output

  ffmpeg version N-76684-g1fe82ab Copyright (c) 2000-2015 the FFmpeg developers
  
    built with gcc 5.2.0 (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-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --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.  6.100 / 55.  6.100
  
    libavcodec     57. 15.100 / 57. 15.100
  
    libavformat    57. 14.100 / 57. 14.100
  
    libavdevice    57.  0.100 / 57.  0.100
  
    libavfilter     6. 15.100 /  6. 15.100
  
    libswscale      4.  0.100 /  4.  0.100
  
    libswresample   2.  0.101 /  2.  0.101
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Input #0, avi, from '720p50_mobcal_ter.avi':
  
    Metadata:
  
      encoder         : Lavf57.14.100
  
    Duration: 00:00:10.08, start: 0.000000, bitrate: 552974 kb/s
  
      Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1280x720, 554059 kb/s, SAR 1:1 DAR 16:9, 50 fps, 50 tbr, 50 tbn, 50 tbc
  
  Input #1, mpegvideo, from 'CUT-720p50_mobcal_ter.mpg':
  
    Duration: N/A, bitrate: N/A
  
      Stream #1:0: Video: mpeg2video (Main), yuv420p(tv), 1280x720 [SAR 1:1 DAR 16:9], max. 104857 kb/s, 50 fps, 50 tbr, 1200k tbn, 100 tbc
  
  [libx264 @ 000002784dbeb980] using SAR=1/1
  
  [libx264 @ 000002784dbeb980] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 000002784dbeb980] profile High, level 3.2
  
  [mpeg @ 000002784dbeaf20] VBV buffer size not set, using default size of 130KB
  
  If you want the mpeg file to be compliant to some specification
  
  Like DVD, VCD or others, make sure you set the correct buffer size
  
  Output #0, mpeg, to 'D:\DOWNLOADS\TMP\Video TDI\AVI\DIFF-720p50_mobcal_ter.mpg':
  
    Metadata:
  
      encoder         : Lavf57.14.100
  
      Stream #0:0: Video: h264 (libx264), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=-1--1, 50 fps, 90k tbn, 50 tbc (default)
  
      Metadata:
  
        encoder         : Lavc57.15.100 libx264
  
  Stream mapping:
  
    Stream #0:0 (rawvideo) -> blend:top
  
    Stream #1:0 (mpeg2video) -> blend:bottom
  
    hue -> Stream #0:0 (libx264)
  
  Press [q] to stop, [?] for help
  
  frame=  504 fps= 39 q=-1.0 Lsize=   32182kB time=00:00:10.04 bitrate=26258.5kbits/s
  
  video:32061kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.377054%
  
  [libx264 @ 000002784dbeb980] frame I:30    Avg QP:19.69  size:149974
  
  [libx264 @ 000002784dbeb980] frame P:299   Avg QP:23.28  size: 69423
  
  [libx264 @ 000002784dbeb980] frame B:175   Avg QP:24.48  size: 43280
  
  [libx264 @ 000002784dbeb980] consecutive B-frames: 30.6% 69.4%  0.0%  0.0%
  
  [libx264 @ 000002784dbeb980] mb I  I16..4: 18.3% 51.4% 30.4%
  
  [libx264 @ 000002784dbeb980] mb P  I16..4:  0.6%  5.6%  2.4%  P16..4: 35.9% 22.9% 15.6%  0.0%  0.0%    skip:17.0%
  
  [libx264 @ 000002784dbeb980] mb B  I16..4:  0.2%  0.5%  0.3%  B16..8: 49.5% 12.4%  5.6%  direct:15.5%  skip:16.1%  L0:47.8% L1:42.1% BI:10.1%
  
  [libx264 @ 000002784dbeb980] 8x8 transform intra:57.5% inter:38.5%
  
  [libx264 @ 000002784dbeb980] coded y,uvDC,uvAC intra: 90.7% 0.0% 0.0% inter: 50.3% 0.0% 0.0%
  
  [libx264 @ 000002784dbeb980] i16 v,h,dc,p: 32% 23% 35% 10%
  
  [libx264 @ 000002784dbeb980] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 11% 11% 41%  7%  5%  6%  5%  6%  8%
  
  [libx264 @ 000002784dbeb980] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 18% 14% 23%  8%  7%  7%  7%  7%  8%
  
  [libx264 @ 000002784dbeb980] i8c dc,h,v,p: 100%  0%  0%  0%
  
  [libx264 @ 000002784dbeb980] Weighted P-Frames: Y:33.8% UV:0.0%
  
  [libx264 @ 000002784dbeb980] ref P L0: 58.1% 16.3% 14.2%  9.4%  2.0%
  
  [libx264 @ 000002784dbeb980] ref B L0: 79.3% 20.7%
  
  [libx264 @ 000002784dbeb980] kb/s:26056.02

  The second command made everything work while the second one in the first part didn’t (the one with the -ss option), so I could be quite happy about it but I’m not that sure if FFMPEG duplicates the first frame for every video or if it’s just related to the one I’m using now, so it could be better to start off with a compressed video that has the same frame count of the original one.

  So let’s get to one final question : why does FFMPEG add a duplicated first frame at the beginning of the compressed video and how can I avoid that ?