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The pirate bay depuis la Belgique
1er avril 2013, par
Mis à jour : Avril 2013
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Autres articles (94)
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Configuration spécifique pour PHP5
4 février 2011, parPHP5 est obligatoire, vous pouvez l’installer en suivant ce tutoriel spécifique.
Il est recommandé dans un premier temps de désactiver le safe_mode, cependant, s’il est correctement configuré et que les binaires nécessaires sont accessibles, MediaSPIP devrait fonctionner correctement avec le safe_mode activé.
Modules spécifiques
Il est nécessaire d’installer certains modules PHP spécifiques, via le gestionnaire de paquet de votre distribution ou manuellement : php5-mysql pour la connectivité avec la (...) -
ANNEXE : Les plugins utilisés spécifiquement pour la ferme
5 mars 2010, parLe site central/maître de la ferme a besoin d’utiliser plusieurs plugins supplémentaires vis à vis des canaux pour son bon fonctionnement. le plugin Gestion de la mutualisation ; le plugin inscription3 pour gérer les inscriptions et les demandes de création d’instance de mutualisation dès l’inscription des utilisateurs ; le plugin verifier qui fournit une API de vérification des champs (utilisé par inscription3) ; le plugin champs extras v2 nécessité par inscription3 (...)
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Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela.
Sur d’autres sites (8941)
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How does FFmpeg determine the “attached pic” and “timed thumbnails” dispositions of an MP4 track ?
6 mars, par obskyrThe Issue


FFmpeg has a concept of “dispositions” – a property that describes the purpose of a stream in a media file. For example, here are the streams in a file I have lying around, with the dispositions emphasized :


Stream #0:0[0x1](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo,
fltp, 251 kb/s <strong><em>(default)</em></strong>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Audio
 vendor_id : [0][0][0][0]

 Stream #0:1[0x2](und): Video: mjpeg (Baseline) (jpeg / 0x6765706A),
yuvj420p(pc, bt470bg/unknown/unknown), 1024x1024, 0 kb/s, 0.0006 fps, 3.08 tbr,
600 tbn <strong><em>(default) (attached pic) (timed thumbnails)</em></strong>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Video
 vendor_id : [0][0][0][0]

 Stream #0:2[0x3](und): Data: bin_data (text / 0x74786574)
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Text

 Stream #0:3[0x0]: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/
unknown), 1024x1024 [SAR 144:144 DAR 1:1], 90k tbr, 90k tbn <strong><em>(attached pic)</em></strong>


However, if I make any modification to this file’s chapter markers using the C++ library MP4v2 (even just re-saving the existing ones :
auto f = MP4Modify("test.m4a"); MP4Chapter_t* chapterList; uint32_t chapterCount; MP4GetChapters(f, &chapterList, &chapterCount); MP4SetChapters(f, chapterList, chapterCount); MP4Close(f);
), some of these dispositions are removed :

Stream #0:0[0x1](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo,
fltp, 251 kb/s <strong><em>(default)</em></strong>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Audio
 vendor_id : [0][0][0][0]

 Stream #0:1[0x2](und): Video: mjpeg (Baseline) (jpeg / 0x6765706A),
yuvj420p(pc, bt470bg/unknown/unknown), 1024x1024, 0 kb/s, 0.0006 fps, 3.08 tbr,
600 tbn <strong><em>(default)</em></strong> <kbd>← “attached pic” and “timed thumbnails” removed!</kbd>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Video
 vendor_id : [0][0][0][0]

 Stream #0:2[0x0]: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/
unknown), 1024x1024 [SAR 144:144 DAR 1:1], 90k tbr, 90k tbn <strong><em>(attached pic)</em></strong>

 Stream #0:3[0x4](und): Data: bin_data (text / 0x74786574)
 <kbd>This stream was moved to the end, but that’s intended behavior. It contains chapter titles, and we just edited the chapters.</kbd>
 Metadata:
 creation_time : 2025-03-05T09:56:31.000000Z


It also renders the file unplayable in MPC-HC (but not in VLC !), which is apparently a bug in MP4v2. I’m currently investigating that bug to report and potentially fix it, but that’s a separate issue – in my journey there, I’m wracking my brain trying to understand what it is that MP4v2 changes to make FFmpeg stop reporting the “attached pic” and “timed thumbnails” dispositions. I’ve explored the before-and-afters in MP4 Box, and I can’t for the life of me find which atom it is that differs in a relevant way.


(I’d love to share the files, but unfortunately the contents are under copyright – if anyone knows of a way to remove the audio from an MP4 file without changing anything else, let me know and I’ll upload dummied-out versions. Without them, I can’t really ask about the issue directly. I can at least show you the files’ respective atom trees, but I’m not sure how relevant that is.)


The Question


I thought I’d read FFmpeg’s source code to find out how it determines dispositions for MP4 streams, but of course, FFmpeg is very complex. Could someone who’s more familiar with C and/or FFmpeg’s codebase help me sleuth out how FFmpeg determines dispositions for MP4 files (in particular, “attached pic” and “timed thumbnails”) ?


Some Thoughts…


- 

- I figure searching for “attached_pic” might be a good start ?
- Could the MP4 muxer
movenc.c
be helpful ? - I’d imagine what we’d really like to look at is the MP4 demuxing process, as it’s during demuxing that FFmpeg determines dispositions from the data in the file. After poring over the code for hours, however, I’ve been utterly unable to find where that happens.








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How does FFmpeg determine the dispositions of an MP4 track ?
5 mars, par obskyrThe Issue


FFmpeg has a concept of “dispositions” – a property that describes the purpose of a stream in a media file. For example, here are the streams in a file I have lying around, with the dispositions emphasized :


Stream #0:0[0x1](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo,
fltp, 251 kb/s <strong><em>(default)</em></strong>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Audio
 vendor_id : [0][0][0][0]

 Stream #0:1[0x2](und): Video: mjpeg (Baseline) (jpeg / 0x6765706A),
yuvj420p(pc, bt470bg/unknown/unknown), 1024x1024, 0 kb/s, 0.0006 fps, 3.08 tbr,
600 tbn <strong><em>(default) (attached pic) (timed thumbnails)</em></strong>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Video
 vendor_id : [0][0][0][0]

 Stream #0:2[0x3](und): Data: bin_data (text / 0x74786574)
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Text

 Stream #0:3[0x0]: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/
unknown), 1024x1024 [SAR 144:144 DAR 1:1], 90k tbr, 90k tbn <strong><em>(attached pic)</em></strong>


However, if I make any modification to this file’s chapter markers using the C++ library MP4v2 (even just re-saving the existing ones :
auto f = MP4Modify("test.m4a"); MP4Chapter_t* chapterList; uint32_t chapterCount; MP4GetChapters(f, &chapterList, &chapterCount); MP4SetChapters(f, chapterList, chapterCount); MP4Close(f);
), some of these dispositions are removed :

Stream #0:0[0x1](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo,
fltp, 251 kb/s <strong><em>(default)</em></strong>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Audio
 vendor_id : [0][0][0][0]

 Stream #0:1[0x2](und): Video: mjpeg (Baseline) (jpeg / 0x6765706A),
yuvj420p(pc, bt470bg/unknown/unknown), 1024x1024, 0 kb/s, 0.0006 fps, 3.08 tbr,
600 tbn <strong><em>(default)</em></strong> <kbd>← “attached pic” and “timed thumbnails” removed!</kbd>
 Metadata:
 creation_time : 2021-11-10T20:14:06.000000Z
 handler_name : Core Media Video
 vendor_id : [0][0][0][0]

 Stream #0:2[0x0]: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/
unknown), 1024x1024 [SAR 144:144 DAR 1:1], 90k tbr, 90k tbn <strong><em>(attached pic)</em></strong>

 Stream #0:3[0x4](und): Data: bin_data (text / 0x74786574)
 <kbd>This stream was moved to the end, but that’s intended behavior. It contains chapter titles, and we just edited the chapters.</kbd>
 Metadata:
 creation_time : 2025-03-05T09:56:31.000000Z


It also renders the file unplayable in MPC-HC (but not in VLC !), which is apparently a bug in MP4v2. I’m currently investigating that bug to report and potentially fix it, but that’s a separate issue – in my journey there, I’m wracking my brain trying to understand what it is that MP4v2 changes to make FFmpeg stop reporting the “attached pic” and “timed thumbnails” dispositions. I’ve explored the before-and-afters in MP4 Box, and I can’t for the life of me find which atom it is that differs in a relevant way.


(I’d love to share the files, but unfortunately the contents are under copyright – if anyone knows of a way to remove the audio from an MP4 file without changing anything else, let me know and I’ll upload dummied-out versions. Without them, I can’t really ask about the issue directly. I can at least show you the files’ respective atom trees, but I’m not sure how relevant that is.)


The Question


I thought I’d read FFmpeg’s source code to find out how it determines dispositions for MP4 streams, but of course, FFmpeg is very complex. Could someone who’s more familiar with C and/or FFmpeg’s codebase help me sleuth out how FFmpeg determines dispositions for MP4 files (in particular, “attached pic” and “timed thumbnails”) ?


Some Thoughts…


- 

- I figure searching for “attached_pic” might be a good start ?
- Could the MP4 muxer
movenc.c
be helpful ? - I’d imagine what we’d really like to look at is the MP4 demuxing process, as it’s during demuxing that FFmpeg determines dispositions from the data in the file. After poring over the code for hours, however, I’ve been utterly unable to find where that happens.








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FFmpeg matlab error : At least one output file must be specified ? [closed]
3 mars, par as mohI'm trying to get I frames from a video using Matlab using this command
system(sprintf('ffmpeg -i testVid.mp4 -vf "select=eq(pict_type\,I)" -vsync vfr output_%03d.png'));
,but i get this message

ffmpeg version 7.1-full_build-www.gyan.dev Copyright (c) 2000-2024 the FFmpeg developers 
 built with gcc 14.2.0 (Rev1, Built by MSYS2 project) 
 configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-libdav1d --enable-libdavs2 --enable-libopenjpeg --enable-libquirc --enable-libuavs3d --enable-libxevd --enable-libzvbi --enable-libqrencode --enable-librav1e --enable-libsvtav1 --enable-libvvenc --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxeve --enable-libxvid --enable-libaom --enable-libjxl --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-dxva2 --enable-d3d11va --enable-d3d12va --enable-ffnvcodec --enable-libvpl --enable-nvdec --enable-nvenc --enable-vaapi --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-liblc3 --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint 
 libavutil 59. 39.100 / 59. 39.100 
 libavcodec 61. 19.100 / 61. 19.100 
 libavformat 61. 7.100 / 61. 7.100 
 libavdevice 61. 3.100 / 61. 3.100 
 libavfilter 10. 4.100 / 10. 4.100 
 libswscale 8. 3.100 / 8. 3.100 
 libswresample 5. 3.100 / 5. 3.100 
 libpostproc 58. 3.100 / 58. 3.100 
Trailing option(s) found in the command: may be ignored. 
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'testVid.mp4': 
 Metadata: 
 major_brand : isom 
 minor_version : 512 
 compatible_brands: isomiso2avc1mp41 
 encoder : Lavf57.83.100 
 Duration: 00:00:02.02, start: 0.000000, bitrate: 12798 kb/s 
 Stream #0:0[0x1](eng): Video: h264 (Baseline) (avc1 / 0x31637661), yuvj420p(pc, progressive), 1280x720 [SAR 1:1 DAR 16:9], 12662 kb/s, 29.74 fps, 30 tbr, 90k tbn (default) 
 Metadata: 
 handler_name : VideoHandler 
 vendor_id : [0][0][0][0] 
 Stream #0:1[0x2](eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 121 kb/s (default) 
 Metadata: 
 handler_name : SoundHandler 
 vendor_id : [0][0][0][0] 
At least one output file must be specified 



i searched and tried many cases but i don't know where is the problem, any help please ?