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Autres articles (76)

  • Gestion générale des documents

    13 mai 2011, par

    MédiaSPIP ne modifie jamais le document original mis en ligne.
    Pour chaque document mis en ligne il effectue deux opérations successives : la création d’une version supplémentaire qui peut être facilement consultée en ligne tout en laissant l’original téléchargeable dans le cas où le document original ne peut être lu dans un navigateur Internet ; la récupération des métadonnées du document original pour illustrer textuellement le fichier ;
    Les tableaux ci-dessous expliquent ce que peut faire MédiaSPIP (...)

  • Participer à sa traduction

    10 avril 2011

    Vous pouvez nous aider à améliorer les locutions utilisées dans le logiciel ou à traduire celui-ci dans n’importe qu’elle nouvelle langue permettant sa diffusion à de nouvelles communautés linguistiques.
    Pour ce faire, on utilise l’interface de traduction de SPIP où l’ensemble des modules de langue de MediaSPIP sont à disposition. ll vous suffit de vous inscrire sur la liste de discussion des traducteurs pour demander plus d’informations.
    Actuellement MediaSPIP n’est disponible qu’en français et (...)

  • Le profil des utilisateurs

    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

Sur d’autres sites (8993)

  • Compensating for missing audio frames in video with ffmpeg [on hold]

    9 décembre 2015, par Ned Rockson

    I consistently have a problem with videos recorded via webrtc where the audio is missing for the first few seconds. With ffmpeg I see that the first audio frame is generally at PTS >1.0.

    This doesn’t cause an issue in isolation as video players are smart enough to adjust, but when using ffmpeg to merge two videos and mix their audio, they end up having offset audio because each audio stream is treated as starting at 0.

    Is there a way to compensate for this offset when using amerge or amix filters ?

  • How to create a video from image buffers using fluent-ffmpeg ?

    23 juin 2016, par Zacky Pickholz

    I’ve been trying to create a slideshow from a series of images using nodejs + fluent-ffmpeg, however it is not working well or consistently. ffmpeg occasionally emits "Error : ffmpeg exited with code 1 : pipe:0 : Invalid data found when processing input", and in case an eventual video (mp4) is created it seems to be missing images/frames.

    The process is as follows : images are loaded into memory, transformed resized to same dimensions using lwip, written sequentially into a passthrough stream, which is fed to ffmpeg as input.

    Relevant code snippets :

    var lwip = require('lwip');
    
var ffmpeg = require('fluent-ffmpeg');
    
var stream = require('stream');
    
var imagesStream = new stream.PassThrough();
    

    
...
    

    
image.batch()
    
            .contain(options.video.width, options.video.height, 'lanczos')
    
            .toBuffer(options.frames.format, {quality: 100}, (err, buffer) => {
    
                if (err) {
    
                    throw ('error convering image to buffer. ' + err);
    
                }
    
                imagesStream.write(buffer, 'utf8');
    
                resolve();
    
            });
    

    
...
    

    
    ffmpeg(imagesStream)
    
        .inputOptions('-framerate 1/' + options.frames.secsPerImage)
    
        .input(path.join(AUDIO_ROOT, options.audio.track))
    
        .save(path.join(path.join(OUTPUT_FOLDER, `${options.video.output.prefix}${timestamp}.${options.video.output.format}`)))
    
        .size(`${options.video.width}x${options.video.height}`)
    
        .on('start', () => {
    
            console.log('creating the clip now...')
    
        })
    
        .on('progress', (progress) => {
    
            var progPercent = Math.round(100 * progress.frames / (numImages * options.frames.secsPerImage * 25));
    
            progPercent = Math.min(progPercent, 100);
    
            console.log(`processing: ${progPercent}% done`)
    
        })
    
        .on('stderr', (line) => {
    
            console.error('ffmpeg error: ' + line);
    
        })
    
        .on('error', (error) => {
    
            reject('ffmpeg transcoding error: ' + error);
    
        })
    
        .on('end', () => {
    
            console.log('done!');
    
            resolve(true);
    
        })
    
        .run();

    And here is the output :

    "C:\Program Files (x86)\JetBrains\WebStorm 2016.1.1\bin\runnerw.exe" "C:\Program Files\nodejs\node.exe" vm2.js
    
image count: 18
    
image count: 6
    
creating the clip now...
    
ffmpeg error: ffmpeg version N-80335-gcb46b78 Copyright (c) 2000-2016 the FFmpeg developers
    
ffmpeg error:   built with gcc 5.4.0 (GCC)
    
ffmpeg error:   configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --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
    
ffmpeg error:   libavutil      55. 24.100 / 55. 24.100
    
ffmpeg error:   libavcodec     57. 46.100 / 57. 46.100
    
ffmpeg error:   libavformat    57. 38.100 / 57. 38.100
    
ffmpeg error:   libavdevice    57.  0.101 / 57.  0.101
    
ffmpeg error:   libavfilter     6. 46.101 /  6. 46.101
    
ffmpeg error:   libswscale      4.  1.100 /  4.  1.100
    
ffmpeg error:   libswresample   2.  1.100 /  2.  1.100
    
ffmpeg error:   libpostproc    54.  0.100 / 54.  0.100
    
creating the clip now...
    
ffmpeg error: ffmpeg version N-80335-gcb46b78 Copyright (c) 2000-2016 the FFmpeg developers
    
ffmpeg error:   built with gcc 5.4.0 (GCC)
    
ffmpeg error:   configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --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
    
ffmpeg error:   libavutil      55. 24.100 / 55. 24.100
    
ffmpeg error:   libavcodec     57. 46.100 / 57. 46.100
    
ffmpeg error:   libavformat    57. 38.100 / 57. 38.100
    
ffmpeg error:   libavdevice    57.  0.101 / 57.  0.101
    
ffmpeg error:   libavfilter     6. 46.101 /  6. 46.101
    
ffmpeg error:   libswscale      4.  1.100 /  4.  1.100
    
ffmpeg error:   libswresample   2.  1.100 /  2.  1.100
    
ffmpeg error:   libpostproc    54.  0.100 / 54.  0.100
    
ffmpeg error: pipe:0: Invalid data found when processing input
    
ffmpeg error: 
    
an error has occurred: ffmpeg transcoding error: Error: ffmpeg exited with code 1: pipe:0: Invalid data found when processing input
    

    
ffmpeg error: [jpeg_pipe @ 0000000000308fe0] Format jpeg_pipe detected only with low score of 6, misdetection possible!
    
ffmpeg error: Input #0, jpeg_pipe, from 'pipe:0':
    
ffmpeg error:   Duration: N/A, bitrate: N/A
    
ffmpeg error:     Stream #0:0: Video: mjpeg, yuvj420p(pc, bt470bg/unknown/unknown), 1920x1080 [SAR 1:1 DAR 16:9], 0.33 tbr, 0.33 tbn, 0.33 tbc
    
ffmpeg error: [mp3 @ 0000000002fa0720] Estimating duration from bitrate, this may be inaccurate
    
ffmpeg error: Input #1, mp3, from 'audio\avicii.mp3':
    
ffmpeg error:   Metadata:
    
ffmpeg error:     album           : True
    
ffmpeg error:     genre           : House
    
ffmpeg error:     copyright       : ℗ 2013 Avicii Music AB, / PRMD under exclusive license to Universal Music AB
    
ffmpeg error:     encoded_by      : Oz
    
ffmpeg error:     title           : Wake Me Up
    
ffmpeg error:     artist          : Avicii
    
ffmpeg error:     album_artist    : Avicii
    
ffmpeg error:     disc            : 1/1
    
ffmpeg error:     track           : 1/12
    
ffmpeg error:     TYER            : 2013-09-13T07:00:00Z
    
ffmpeg error:   Duration: 00:04:09.73, start: 0.000000, bitrate: 321 kb/s
    
ffmpeg error:     Stream #1:0: Audio: mp3, 44100 Hz, stereo, s16p, 320 kb/s
    
ffmpeg error:     Stream #1:1: Video: mjpeg, yuvj444p(pc, bt470bg/unknown/unknown), 600x600 [SAR 305:305 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
    
ffmpeg error:     Metadata:
    
ffmpeg error:       comment         : Cover (front)
    
ffmpeg error: No pixel format specified, yuvj420p for H.264 encoding chosen.
    
ffmpeg error: Use -pix_fmt yuv420p for compatibility with outdated media players.
    
ffmpeg error: [libx264 @ 000000000030e860] using SAR=1/1
    
ffmpeg error: [libx264 @ 000000000030e860] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
    
ffmpeg error: [libx264 @ 000000000030e860] profile High, level 4.0
    
ffmpeg error: [libx264 @ 000000000030e860] 264 - core 148 r2694 3b70645 - H.264/MPEG-4 AVC codec - Copyleft 2003-2016 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=12 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
    
ffmpeg error: [mp4 @ 0000000002ec6980] Using AVStream.codec to pass codec parameters to muxers is deprecated, use AVStream.codecpar instead.
    
ffmpeg error:     Last message repeated 1 times
    
ffmpeg error: Output #0, mp4, to 'output\clip_2016-06-22_06-17-25.mp4':
    
ffmpeg error:   Metadata:
    
ffmpeg error:     encoder         : Lavf57.38.100
    
ffmpeg error:     Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuvj420p(pc), 1920x1080 [SAR 1:1 DAR 16:9], q=-1--1, 25 fps, 12800 tbn, 25 tbc
    
ffmpeg error:     Metadata:
    
ffmpeg error:       encoder         : Lavc57.46.100 libx264
    
ffmpeg error:     Side data:
    
ffmpeg error:       cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
    
ffmpeg error:     Stream #0:1: Audio: aac (LC) ([64][0][0][0] / 0x0040), 44100 Hz, stereo, fltp, 128 kb/s
    
ffmpeg error:     Metadata:
    
ffmpeg error:       encoder         : Lavc57.46.100 aac
    
ffmpeg error: Stream mapping:
    
ffmpeg error:   Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
    
ffmpeg error:   Stream #1:0 -> #0:1 (mp3 (native) -> aac (native))
    
ffmpeg error: frame=   75 fps=0.0 q=28.0 size=       0kB time=00:00:00.64 bitrate=   0.6kbits/s dup=74 drop=0 speed=1.09x    
    
processing: 17% done
    
ffmpeg error: frame=  150 fps= 97 q=28.0 size=     371kB time=00:00:03.64 bitrate= 835.6kbits/s dup=148 drop=0 speed=2.35x    
    
processing: 33% done
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 73 q=28.0 size=     879kB time=00:00:07.36 bitrate= 977.8kbits/s dup=148 drop=0 speed= 3.6x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 59 q=28.0 size=     952kB time=00:00:18.36 bitrate= 424.7kbits/s dup=148 drop=0 speed=7.21x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 49 q=28.0 size=    1190kB time=00:00:32.99 bitrate= 295.3kbits/s dup=148 drop=0 speed=10.8x    
    
ffmpeg error: frame=  150 fps= 42 q=28.0 size=    1409kB time=00:00:46.64 bitrate= 247.4kbits/s dup=148 drop=0 speed=13.1x    
    
processing: 33% done
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 37 q=28.0 size=    1628kB time=00:01:00.30 bitrate= 221.1kbits/s dup=148 drop=0 speed=14.9x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 33 q=28.0 size=    1878kB time=00:01:15.83 bitrate= 202.8kbits/s dup=148 drop=0 speed=16.7x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 30 q=28.0 size=    2130kB time=00:01:31.64 bitrate= 190.4kbits/s dup=148 drop=0 speed=18.2x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 27 q=28.0 size=    2375kB time=00:01:47.18 bitrate= 181.5kbits/s dup=148 drop=0 speed=19.3x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 25 q=28.0 size=    2626kB time=00:02:03.15 bitrate= 174.7kbits/s dup=148 drop=0 speed=20.4x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 23 q=28.0 size=    2832kB time=00:02:16.20 bitrate= 170.3kbits/s dup=148 drop=0 speed=20.8x    
    
ffmpeg error: frame=  150 fps= 21 q=28.0 size=    3063kB time=00:02:30.34 bitrate= 166.9kbits/s dup=148 drop=0 speed=21.3x    
    
processing: 33% done
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 20 q=28.0 size=    3298kB time=00:02:44.93 bitrate= 163.8kbits/s dup=148 drop=0 speed=21.8x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 19 q=28.0 size=    3522kB time=00:02:58.93 bitrate= 161.3kbits/s dup=148 drop=0 speed=22.2x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 18 q=28.0 size=    3792kB time=00:03:15.83 bitrate= 158.6kbits/s dup=148 drop=0 speed=22.9x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 17 q=28.0 size=    4035kB time=00:03:31.11 bitrate= 156.6kbits/s dup=148 drop=0 speed=23.3x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 16 q=28.0 size=    4294kB time=00:03:47.62 bitrate= 154.5kbits/s dup=148 drop=0 speed=23.8x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 15 q=28.0 size=    4566kB time=00:04:04.87 bitrate= 152.7kbits/s dup=148 drop=0 speed=24.4x    
    
processing: 33% done
    
ffmpeg error: frame=  150 fps= 14 q=-1.0 Lsize=    4851kB time=00:04:09.73 bitrate= 159.1kbits/s dup=148 drop=0 speed=23.6x    
    
ffmpeg error: video:826kB audio:3978kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.967442%
    
ffmpeg error: [libx264 @ 000000000030e860] frame I:2     Avg QP:14.53  size:414604
    
ffmpeg error: [libx264 @ 000000000030e860] frame P:38    Avg QP:16.59  size:   222
    
ffmpeg error: [libx264 @ 000000000030e860] frame B:110   Avg QP:12.67  size:    69
    
ffmpeg error: [libx264 @ 000000000030e860] consecutive B-frames:  1.3%  2.7%  0.0% 96.0%
    
ffmpeg error: [libx264 @ 000000000030e860] mb I  I16..4: 25.5% 49.4% 25.1%
    
ffmpeg error: [libx264 @ 000000000030e860] mb P  I16..4:  0.0%  0.0%  0.0%  P16..4:  0.7%  0.0%  0.0%  0.0%  0.0%    skip:99.2%
    
ffmpeg error: [libx264 @ 000000000030e860] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  0.0%  0.0%  0.0%  direct: 0.0%  skip:100.0%  L0: 1.2% L1:98.8% BI: 0.0%
    
ffmpeg error: [libx264 @ 000000000030e860] 8x8 transform intra:49.4% inter:92.1%
    
ffmpeg error: [libx264 @ 000000000030e860] coded y,uvDC,uvAC intra: 74.2% 73.7% 69.0% inter: 0.0% 0.2% 0.0%
    
ffmpeg error: [libx264 @ 000000000030e860] i16 v,h,dc,p: 97%  0%  2%  1%
    
ffmpeg error: [libx264 @ 000000000030e860] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 13% 19% 15%  7%  9%  7% 10%  7% 13%
    
ffmpeg error: [libx264 @ 000000000030e860] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 12% 21%  8%  8% 11%  9% 12%  7% 13%
    
ffmpeg error: [libx264 @ 000000000030e860] i8c dc,h,v,p: 55% 19% 16% 10%
    
ffmpeg error: [libx264 @ 000000000030e860] Weighted P-Frames: Y:0.0% UV:0.0%
    
ffmpeg error: [libx264 @ 000000000030e860] ref P L0: 95.4%  0.6%  3.1%  0.9%
    
ffmpeg error: [libx264 @ 000000000030e860] ref B L1: 98.8%  1.2%
    
ffmpeg error: [libx264 @ 000000000030e860] kb/s:1127.01
    
ffmpeg error: [aac @ 0000000002ecc880] Qavg: 541.237
    
ffmpeg error: 
    
done!

  • ffmpeg mapping to mkv introduces "fake" delay relative to video

    1er août 2016, par JMor

    I need to map this x.264 clip into a matroska container using ffmpeg :

    ffmpeg -i f-0.mp4 -c copy f-0.mkv

    Here is the ffmpeg console output :

    ffmpeg -i f-0.mp4 -c copy f-0.mkv   
    
ffmpeg version N-69672-g078be09 Copyright (c) 2000-2015 the FFmpeg developers
    
  built with gcc 4.9.2 (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-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-lzma --enable-decklink --enable-zlib
    
  libavutil      54. 18.100 / 54. 18.100
    
  libavcodec     56. 21.102 / 56. 21.102
    
  libavformat    56. 19.100 / 56. 19.100
    
  libavdevice    56.  4.100 / 56.  4.100
    
  libavfilter     5.  9.104 /  5.  9.104
    
  libswscale      3.  1.101 /  3.  1.101
    
  libswresample   1.  1.100 /  1.  1.100
    
  libpostproc    53.  3.100 / 53.  3.100
    
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'f-0.mp4':
    
  Metadata:
    
    major_brand     : isom
    
    minor_version   : 512
    
    compatible_brands: isomiso2avc1mp41
    
    encoder         : Lavf56.19.100
    
  Duration: 00:02:08.06, start: 0.005333, bitrate: 5030 kb/s
    
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 4865 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
    
    Metadata:
    
      handler_name    : VideoHandler
    
    Stream #0:1(und): Audio: ac3 (ac-3 / 0x332D6361), 48000 Hz, stereo, fltp, 160 kb/s (default)
    
    Metadata:
    
      handler_name    : SoundHandler
    
    Side data:
    
      unknown side data type 7 (4 bytes)
    
Output #0, matroska, to 'f-0.mkv':
    
  Metadata:
    
    major_brand     : isom
    
    minor_version   : 512
    
    compatible_brands: isomiso2avc1mp41
    
    encoder         : Lavf56.19.100
    
    Stream #0:0(und): Video: h264 (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 4865 kb/s, 29.97 fps, 29.97 tbr, 1k tbn, 30k tbc (default)
    
    Metadata:
    
      handler_name    : VideoHandler
    
    Stream #0:1(und): Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, stereo, 160 kb/s (default)
    
    Metadata:
    
      handler_name    : SoundHandler
    
    Side data:
    
      unknown side data type 7 (4 bytes)
    
Stream mapping:
    
  Stream #0:0 -> #0:0 (copy)
    
  Stream #0:1 -> #0:1 (copy)
    
...

    The result seems good, playing with well synchronized audio and video. However, MediaInfo shows a new item under Audio (that the original clip didn’t have) :

    Delay relative to video                  : 1mn 5s

    Here is the Mediainfo from the original f-0.mp4 file :

    Audio
    
  ID                                       : 2
    
  Format                                   : AC-3
    
  Format/Info                              : Audio Coding 3
    
  Mode extension                           : CM (complete main)
    
  Format settings, Endianness              : Big
    
  Codec ID                                 : ac-3
    
  Duration                                 : 2mn 8s
    
  Bit rate mode                            : Constant
    
  Bit rate                                 : 160 Kbps
    
  Channel(s)                               : 2 channels
    
  Channel positions                        : Front: L R
    
  Sampling rate                            : 48.0 KHz
    
  Bit depth                                : 16 bits
    
  Compression mode                         : Lossy
    
  Delay relative to video                  : 67ms
    
  Stream size                              : 2.44 MiB (3%)

    Mediainfo from the f-0.mkv output :

    Audio
    
  ID                                       : 2
    
  Format                                   : AC-3
    
  Format/Info                              : Audio Coding 3
    
  Mode extension                           : CM (complete main)
    
  Format settings, Endianness              : Big
    
  Codec ID                                 : A_AC3
    
  Duration                                 : 2mn 8s
    
  Bit rate mode                            : Constant
    
  Bit rate                                 : 160 Kbps
    
  Channel(s)                               : 2 channels
    
  Channel positions                        : Front: L R
    
  Sampling rate                            : 48.0 KHz
    
  Bit depth                                : 16 bits
    
  Compression mode                         : Lossy
    
  Delay relative to video                  : 1mn 5s
    
  Stream size                              : 2.44 MiB (3%)
    
  Default                                  : Yes
    
  Forced                                   : No
    
  HANDLER_NAME                             : SoundHandler

    There is no delay whatsoever and no reason to insert a delay.

    I am concerned that this information (Delay relative to video) be used by some players or other applications as a delay that should be corrected. Is there a way to prevent this from happening ?

    Adding ffprobe output : f-0.mp4 clip

    ffprobe -show_entries stream=codec_type,duration,start_time -of compact f-0.mp4
    
    ffprobe version N-69672-g078be09 Copyright (c) 2007-2015 the FFmpeg developers
    
    built with gcc 4.9.2 (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-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-lzma --enable-decklink --enable-zlib
    
    libavutil      54. 18.100 / 54. 18.100
    
    libavcodec     56. 21.102 / 56. 21.102
    
    libavformat    56. 19.100 / 56. 19.100
    
    libavdevice    56.  4.100 / 56.  4.100
    
    libavfilter     5.  9.104 /  5.  9.104
    
    libswscale      3.  1.101 /  3.  1.101
    
    libswresample   1.  1.100 /  1.  1.100
    
    libpostproc    53.  3.100 / 53.  3.100
    
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'f-0.mp4':
    
    Metadata:
    
      major_brand     : isom
    
      minor_version   : 512
    
      compatible_brands: isomiso2avc1mp41
    
      encoder         : Lavf56.19.100
    
    Duration: 00:02:08.06, start: 0.005333, bitrate: 5030 kb/s
    
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 4865 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
    
      Metadata:
    
        handler_name    : VideoHandler
    
      Stream #0:1(und): Audio: ac3 (ac-3 / 0x332D6361), 48000 Hz, stereo, fltp, 160 kb/s (default)
    
      Metadata:
    
        handler_name    : SoundHandler
    
      Side data:
    
        unknown side data type 7 (4 bytes)
    
  stream|codec_type=video|start_time=0.000000|duration=128.061267
    
  stream|codec_type=audio|start_time=-0.005333|duration=128.064000

    f-0.mkv clip :

    ffprobe version N-69672-g078be09 Copyright (c) 2007-2015 the FFmpeg developers
    
  built with gcc 4.9.2 (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-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-lzma --enable-decklink --enable-zlib
    
  libavutil      54. 18.100 / 54. 18.100
    
  libavcodec     56. 21.102 / 56. 21.102
    
  libavformat    56. 19.100 / 56. 19.100
    
  libavdevice    56.  4.100 / 56.  4.100
    
  libavfilter     5.  9.104 /  5.  9.104
    
  libswscale      3.  1.101 /  3.  1.101
    
  libswresample   1.  1.100 /  1.  1.100
    
  libpostproc    53.  3.100 / 53.  3.100
    
Input #0, matroska,webm, from 'f-0.mkv':
    
  Metadata:
    
    COMPATIBLE_BRANDS: isomiso2avc1mp41
    
    MAJOR_BRAND     : isom
    
    MINOR_VERSION   : 512
    
    ENCODER         : Lavf56.19.100
    
  Duration: 00:02:08.13, start: 0.061000, bitrate: 5026 kb/s
    
    Stream #0:0(und): Video: h264 (High), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 29.97 fps, 29.97 tbr, 1k tbn, 59.94 tbc (default)
    
    Metadata:
    
      LANGUAGE        : und
    
      HANDLER_NAME    : VideoHandler
    
    Stream #0:1(und): Audio: ac3, 48000 Hz, stereo, fltp, 160 kb/s (default)
    
    Metadata:
    
      LANGUAGE        : und
    
      HANDLER_NAME    : SoundHandler
    
stream|codec_type=video|start_time=0.066000|duration=N/A
    
stream|codec_type=audio|start_time=0.061000|duration=N/A

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