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Richard Stallman et le logiciel libre
19 octobre 2011, par
Mis à jour : Mai 2013
Langue : français
Type : Texte
Autres articles (95)
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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. -
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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Installation en mode standalone
4 février 2011, parL’installation de la distribution MediaSPIP se fait en plusieurs étapes : la récupération des fichiers nécessaires. À ce moment là deux méthodes sont possibles : en installant l’archive ZIP contenant l’ensemble de la distribution ; via SVN en récupérant les sources de chaque modules séparément ; la préconfiguration ; l’installation définitive ;
[mediaspip_zip]Installation de l’archive ZIP de MediaSPIP
Ce mode d’installation est la méthode la plus simple afin d’installer l’ensemble de la distribution (...)
Sur d’autres sites (8214)
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How to convert VP8 track with different frame resolution to h264
13 septembre 2016, par NikitaI have a .webm file with VP8 track, recorded from WebRTC stream by external service (TokBox Archiving). The stream is adaptive, so each frame in track could have different resolution. Most players (in webkit browsers) use video resolution from track description (which is always 640x480) and scale frames to this resolution. Firefox and VLC player uses real frame resolution, changing video resolution respectively.
I want to achieve 2 goals :
- play this video in Internet Explorer 9+ without additional plugin installation.
- change frames resolution to one fixed resolution, so the video will look identically in different browsers.
So, my plan is :
- extract frames from source webm file to images with real frame resolution (e.g. PNG or BMP) (how could I do that ?)
- find max width and max height of images
- add black padding to images, so smaller frames will be in the center of a new frame (of size MAX_WIDHTxMAX_HEIGHT)
- combine images to h264 track using ffmpeg
Is all correct ? How can I achieve this ? Can this algorithm be optimized some way ?
I tried ffmpeg to extract images, but it does not parse real frame resolution, using resolution from track header.
I think some libwebm functions can help me (to parse frame headers and extract images). Maybe someone has some code snippets to do this ?Example .webm (download source, do not play google-converted version) : https://drive.google.com/file/d/0BwFZRvYNn9CKcndhMzlVa0psX00/view?usp=sharing
Official description of adaptive stream from TokBox support : https://support.tokbox.com/hc/en-us/community/posts/206241666-Archived-video-resolution-is-supposed-to-be-720x1280-but-reports-as-640x480
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Can x264 be used from Java code via JNI to decrease the resolution of RTMP streams ? [on hold]
5 septembre 2016, par Orr151I would like to implement a custom RTMP transcoder to HLS format in Java. As the repackaging itself seems to be relatively clear and doable in Java, then I found the modification of the video resolution a bit challenging in Java. My plan is to avoid using existing solutions like FFmpeg or at least minimize the amount of 3rd party frameworks/tools integrated with my component.
After some research it seems that reusage of JCodec and Xuggler can be challenging as both project are idle for a while. Also I’m not sure if their performance is acceptable. That’s why I would like to integrate directly with x264 library via JNI from Java code.
Is integration with x264/libx264 from Java code to decrease resolution/bitrate doable and is it a good idea ? Could you please suggest any other solutions ?
Thanks !
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Can x264 be used from Java code via JNI to decrease the resolution of RTMP streams ? [on hold]
5 septembre 2016, par Orr151I would like to implement a custom RTMP transcoder to HLS format in Java. As the repackaging itself seems to be relatively clear and doable in Java, then I found the modification of the video resolution a bit challenging in Java. My plan is to avoid using existing solutions like FFmpeg or at least minimize the amount of 3rd party frameworks/tools integrated with my component.
After some research it seems that reusage of JCodec and Xuggler can be challenging as both project are idle for a while. Also I’m not sure if their performance is acceptable. That’s why I would like to integrate directly with x264 library via JNI from Java code.
Is integration with x264/libx264 from Java code to decrease resolution/bitrate doable and is it a good idea ? Could you please suggest any other solutions ?
Thanks !