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  • Organiser par catégorie

    17 May 2013, by

    Dans MédiaSPIP, une rubrique a 2 noms : catégorie et rubrique.
    Les différents documents stockés dans MédiaSPIP peuvent être rangés dans différentes catégories. On peut créer une catégorie en cliquant sur "publier une catégorie" dans le menu publier en haut à droite ( après authentification ). Une catégorie peut être rangée dans une autre catégorie aussi ce qui fait qu’on peut construire une arborescence de catégories.
    Lors de la publication prochaine d’un document, la nouvelle catégorie créée sera proposée (...)

  • Création définitive du canal

    12 March 2010, by

    Lorsque votre demande est validée, vous pouvez alors procéder à la création proprement dite du canal. Chaque canal est un site à part entière placé sous votre responsabilité. Les administrateurs de la plateforme n’y ont aucun accès.
    A la validation, vous recevez un email vous invitant donc à créer votre canal.
    Pour ce faire il vous suffit de vous rendre à son adresse, dans notre exemple "http://votre_sous_domaine.mediaspip.net".
    A ce moment là un mot de passe vous est demandé, il vous suffit d’y (...)

  • Le profil des utilisateurs

    12 April 2011, by

    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 (...)

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  • How to calculate vmaf score of multi-resolution webm using ffmpeg?

    13 July 2022, by will

    I’m trying to calculate the vmaf of two videos, one is avi(rawvideo(I420), yuv420p), the other is webm(vp8, yuv420p). I uploaded test video and vmaf log here.

    


    But I found that if it’s a multi-resolution webm, the scores obtained with and without fps filter are quite different. Without fps filter the vmaf score is 34.670390, with fps filter the vmaf score is 56.339923.

    


    If it‘s a single resolution webm, there is no significant difference between the scores obtained with and without fps filter. Without fps filter the vmaf score is 65.527304, with fps filter the vmaf score is 65.480217.

    


    I use these commands.

    


    without fps filter

    


    ffmpeg \
    -r 15 -i reference.avi \
    -r 15 -i distorted.webm \
    -lavfi "[0:v]setpts=PTS-STARTPTS[reference]; \
            [1:v]scale=1920:1080:flags=bicubic,setpts=PTS-STARTPTS[distorted]; \
            [distorted][reference]libvmaf=log_fmt=json:log_path=vmaf_without_fps.log:model_path=vmaf_v0.6.1.json:n_threads=10:ssim=1:psnr=1" \
    -f null -


    


    ffmpeg version 4.4.1 Copyright (c) 2000-2021 the FFmpeg developers
  built with Apple clang version 12.0.0 (clang-1200.0.32.29)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.4.1_3 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-avresample --enable-videotoolbox
  libavutil      56. 70.100 / 56. 70.100
  libavcodec     58.134.100 / 58.134.100
  libavformat    58. 76.100 / 58. 76.100
  libavdevice    58. 13.100 / 58. 13.100
  libavfilter     7.110.100 /  7.110.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  9.100 /  5.  9.100
  libswresample   3.  9.100 /  3.  9.100
  libpostproc    55.  9.100 / 55.  9.100
Input #0, avi, from 'reference.avi':
  Metadata:
    software        : Lavf58.76.100
  Duration: 00:00:26.13, start: 0.000000, bitrate: 373260 kb/s
  Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1920x1080, 374202 kb/s, 15 fps, 15 tbr, 15 tbn, 15 tbc
Input #1, matroska,webm, from 'distorted.webm':
  Metadata:
    encoder         : Chrome
  Duration: N/A, start: 0.000000, bitrate: N/A
  Stream #1:0(eng): Audio: opus, 48000 Hz, stereo, fltp (default)
  Stream #1:1(eng): Video: vp8, yuv420p(progressive), 1920x1080, SAR 1:1 DAR 16:9, 1k tbr, 1k tbn, 1k tbc (default)
    Metadata:
      alpha_mode      : 1
Stream mapping:
  Stream #0:0 (rawvideo) -> setpts (graph 0)
  Stream #1:1 (vp8) -> scale (graph 0)
  libvmaf (graph 0) -> Stream #0:0 (wrapped_avframe)
  Stream #1:0 -> #0:1 (opus (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
libvmaf INFO `compute_vmaf()` is deprecated and will be removed in a future libvmaf version
Output #0, null, to 'pipe:':
  Metadata:
    software        : Lavf58.76.100
    encoder         : Lavf58.76.100
  Stream #0:0: Video: wrapped_avframe, yuv420p(tv, bt470bg/unknown/unknown, progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 15 fps, 15 tbn (default)
    Metadata:
      encoder         : Lavc58.134.100 wrapped_avframe
  Stream #0:1(eng): Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s (default)
    Metadata:
      encoder         : Lavc58.134.100 pcm_s16le
[libvmaf @ 0x7feb8a606a80] VMAF score: 58.1203705.87 bitrate=N/A speed= 5.6x    
libvmaf INFO `compute_vmaf()` is deprecated and will be removed in a future libvmaf version
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 0
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 1
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 2
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 3
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 4
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 5
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 6
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 7
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 8
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 9
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 10
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 11
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 12
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 13
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 14
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 15
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 16
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 17
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 18
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 19
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 20
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 21
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 22
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 23
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 24
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 25
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 26
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 27
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 28
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 29
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 30
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 31
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 32
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 33
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 34
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 35
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 36
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 37
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 38
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 39
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 40
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 41
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 42
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 43
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 44
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 45
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 46
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 47
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 48
[null @ 0x7feb8b04da00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 49 >= 49
frame=  392 fps= 36 q=-0.0 Lsize=N/A time=00:00:28.73 bitrate=N/A speed= 2.6x    
video:205kB audio:5400kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
[libvmaf @ 0x7feb8c405bc0] VMAF score: 34.670390


    


    with fps filter

    


    ffmpeg \
    -r 15 -i reference.avi \
    -r 15 -i distorted.webm \
    -lavfi "[0:v]setpts=PTS-STARTPTS[reference]; \
            [1:v]fps=fps=15,scale=1920:1080:flags=bicubic,setpts=PTS-STARTPTS[distorted]; \
            [distorted][reference]libvmaf=log_fmt=json:log_path=vmaf_with_fps.log:model_path=vmaf_v0.6.1.json:n_threads=10:ssim=1:psnr=1" \
    -f null -


    


    ffmpeg version 4.4.1 Copyright (c) 2000-2021 the FFmpeg developers
  built with Apple clang version 12.0.0 (clang-1200.0.32.29)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.4.1_3 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-avresample --enable-videotoolbox
  libavutil      56. 70.100 / 56. 70.100
  libavcodec     58.134.100 / 58.134.100
  libavformat    58. 76.100 / 58. 76.100
  libavdevice    58. 13.100 / 58. 13.100
  libavfilter     7.110.100 /  7.110.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  9.100 /  5.  9.100
  libswresample   3.  9.100 /  3.  9.100
  libpostproc    55.  9.100 / 55.  9.100
Input #0, avi, from 'reference.avi':
  Metadata:
    software        : Lavf58.76.100
  Duration: 00:00:26.13, start: 0.000000, bitrate: 373260 kb/s
  Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1920x1080, 374202 kb/s, 15 fps, 15 tbr, 15 tbn, 15 tbc
Input #1, matroska,webm, from 'distorted.webm':
  Metadata:
    encoder         : Chrome
  Duration: N/A, start: 0.000000, bitrate: N/A
  Stream #1:0(eng): Audio: opus, 48000 Hz, stereo, fltp (default)
  Stream #1:1(eng): Video: vp8, yuv420p(progressive), 1920x1080, SAR 1:1 DAR 16:9, 1k tbr, 1k tbn, 1k tbc (default)
    Metadata:
      alpha_mode      : 1
Stream mapping:
  Stream #0:0 (rawvideo) -> setpts (graph 0)
  Stream #1:1 (vp8) -> fps (graph 0)
  libvmaf (graph 0) -> Stream #0:0 (wrapped_avframe)
  Stream #1:0 -> #0:1 (opus (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
libvmaf INFO `compute_vmaf()` is deprecated and will be removed in a future libvmaf version
Output #0, null, to 'pipe:':
  Metadata:
    software        : Lavf58.76.100
    encoder         : Lavf58.76.100
  Stream #0:0: Video: wrapped_avframe, yuv420p(tv, bt470bg/unknown/unknown, progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 15 fps, 15 tbn (default)
    Metadata:
      encoder         : Lavc58.134.100 wrapped_avframe
  Stream #0:1(eng): Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s (default)
    Metadata:
      encoder         : Lavc58.134.100 pcm_s16le
[libvmaf @ 0x7fdeab00bac0] VMAF score: 58.3160815.27 bitrate=N/A speed=5.08x    
libvmaf INFO `compute_vmaf()` is deprecated and will be removed in a future libvmaf version
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 0
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 1
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 2
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 3
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 4
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 5
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 6
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 7
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 8
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 9
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 10
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 11
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 12
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 13
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 14
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 15
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 16
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 17
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 18
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 19
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 20
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 21
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 22
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 23
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 24
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 25
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 26
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 27
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 28
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 29
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 30
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 31
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 32
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 33
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 34
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 35
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 36
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 37
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 38
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 39
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 40
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 41
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 42
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 43
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 44
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 45
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 46
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 47
[null @ 0x7fdeab84ba00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 48 >= 48
frame=  391 fps= 36 q=-0.0 Lsize=N/A time=00:00:28.73 bitrate=N/A speed=2.62x    
video:205kB audio:5400kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
[libvmaf @ 0x7fdea9f34a00] VMAF score: 56.339923


    


    I'm curious about what causes such a difference? And how to calculate vmaf score of multi-resolution webm correctly?

    


  • Revision 3331: On ajoute un accès à la configuration dans les menus

    25 April 2010, by kent1 — Log

    On ajoute un accès à la configuration dans les menus

  • Révision 23073: Encore une amélioration dans la gestion des caches compressés. Dans le cas des ca...

    27 June 2016, by esj@rezo.net

    Pour s’assurer que le 2e fichier est bien postérieur au 1er (cas du squelette d’origine modifié ultérieurement et inroduit dans le cache par une autre session) on utilise filemtime comme le faisait le code de r15851 à l’origine (r15852 ne précise pas pourquoi une autre méthode, incompatible avec la stratégie d’aujourd’hui, serait meilleure).