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Que fait exactement ce script ?
18 janvier 2011, parCe script est écrit en bash. Il est donc facilement utilisable sur n’importe quel serveur.
Il n’est compatible qu’avec une liste de distributions précises (voir Liste des distributions compatibles).
Installation de dépendances de MediaSPIP
Son rôle principal est d’installer l’ensemble des dépendances logicielles nécessaires coté serveur à savoir :
Les outils de base pour pouvoir installer le reste des dépendances Les outils de développements : build-essential (via APT depuis les dépôts officiels) ; (...) -
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 (6039)
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avutil/frame : document alignment and padding requirements
17 mars 2013, par Michael Niedermayeravutil/frame : document alignment and padding requirements
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avutil/log : document log callback thread saftey requirements
17 octobre 2013, par Michael Niedermayer -
In what way does this HEVC video not comply to Apples's requirements document ?
16 novembre 2022, par Duke DougalMy goal is to work out why a given video file does not play on Macos/Safari/Quicktime.


The background to this question is that it is possible to play HEVC videos with a transparent background/alpha channel on Safari/MacOS. To be playable, a video must meet the specific requirements set out by Apple in this document :


https://developer.apple.com/av-foundation/HEVC-Video-with-Alpha-Interoperability-Profile.pdf


The video that does not play on Apple/Safari/Quicktime is an HEVC video with an alpha transparency channel. Note that VLC for MacOS DOES play this file. Here it is :


https://drive.google.com/file/d/1ZnXjcDbk-_YxTgRuH_D7RSR9SXdY_XTv/view?usp=share_link


I have two example HEVC video files with a transparent background/alpha channel, and they both play fine using either Quicktime player or Safari :


Working video #1 :


https://drive.google.com/file/d/1PJAyg_sVKVvb-Py8PAu42c1qm8l2qCbh/view?usp=share_link


Working video #2 :


https://drive.google.com/file/d/1kk8ssUyT7qAaK15afp8VPR6mIWPFX8vQ/view?usp=sharing


The first step is to work out in what way my non-working video ( https://drive.google.com/file/d/1ZnXjcDbk-_YxTgRuH_D7RSR9SXdY_XTv/view?usp=share_link ) does not comply with the specification.


Once it is clear which requirements are not met by the non-working video then I can move onto the next phase, which is to try to formulate an ffmpeg command that will output a video meeting the requirements.


I have read Apples requirements document and I am out of my depth in trying to analyse the non working video against the requirements - I don't know how to do it.


Can anyone suggest a way to identify what is wrong with the video ?


Additional context is that I am trying to find a way to create Apple/MacOS compatible alpha channel / transparent videos using ffmpeg with hevc_nvenc running on an Intel machine. I am aware that Apple hardware can create such videos, but for a wide variety of reasons it is not practical for me to use Apple hardware to do the job. I have spent many hours trying all sorts of ffmpeg and ffprobe commands to try to work out what is wrong and modify the video to fix it, but to be honest most of my attempts are guesswork.


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