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Emballe médias : à quoi cela sert ?
4 février 2011, parCe plugin vise à gérer des sites de mise en ligne de documents de tous types.
Il crée des "médias", à savoir : un "média" est un article au sens SPIP créé automatiquement lors du téléversement d’un document qu’il soit audio, vidéo, image ou textuel ; un seul document ne peut être lié à un article dit "média" ; -
Supporting all media types
13 avril 2011, parUnlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)
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Pas question de marché, de cloud etc...
10 avril 2011Le vocabulaire utilisé sur ce site essaie d’éviter toute référence à la mode qui fleurit allègrement
sur le web 2.0 et dans les entreprises qui en vivent.
Vous êtes donc invité à bannir l’utilisation des termes "Brand", "Cloud", "Marché" etc...
Notre motivation est avant tout de créer un outil simple, accessible à pour tout le monde, favorisant
le partage de créations sur Internet et permettant aux auteurs de garder une autonomie optimale.
Aucun "contrat Gold ou Premium" n’est donc prévu, aucun (...)
Sur d’autres sites (6993)
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Displaying text on video while recording and if saved then also (add text to video when start recording)
25 novembre 2017, par J4GD33P 51NGHi’m using this android project from git hub and now want to add text to video when start recording. text should also there if we watch saved video later. can anyone suggest me an idea to do this.
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Displaying text on video while recording and if saved then also(add text to video when start recording)
25 novembre 2017, par J4GD33P 51NGHi’m using this android project from git hub and now want to add text to video when start recording. text should also there if we watch saved video later. can anyone suggest me an idea to do this.
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Issue with MJPEG stream playback speed when encoding with FFmpeg
6 janvier, par ArciiixI'm working with a MJPEG stream source


Stream #0:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 1280x720 [SAR 1:1 DAR 16:9], 25 tbr, 25 tbn


I want to capture this stream and save it to an MP4 file using FFmpeg, but I am running into a weird issue.


The only way it works fine is when I just copy the stream without reencoding and using wallclock as timestamps (cmd 1) :


ffmpeg -use_wallclock_as_timestamps 1 -i "http://IP/video/1280x720" -c:v copy output_good.mp4



However, when I try encoding the stream with libx264, the playback speed of the resulting video becomes slower than 100%, causing the video to gradually fall out of sync with real-time. This happens even when I use any encoding, also when I explicitly set the frame rate or vsync. For example, these commands fail :


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- CMD 2 :
ffmpeg -i "http://IP/video/1280x720" -c:v libx264 -r 30 -preset fast output_bad1.mp4
- CMD 3 :
ffmpeg -use_wallclock_as_timestamps 1 -i "http://IP/video/1280x720" -c:v libx264 output.mp4






https://www.youtube.com/watch?v=PF0fuCu7Xao


As you can see in the comparison of the resulting videos, the playback gradually slows down with CMD 2 and CMD 3, while it's alright with CMD 1.


What I've noticed is that on the FFmpeg stdout, when using encoding, the
speed=
andFPS=
go up and up, e.g. to 31 FPS even though my source is technically at 25 FPS.

What I've tried :


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- different encoding codecs (e.g. libvpx)
- -re
- preset ultrafast on encoding
- vsync (fps_mode), both ctr and vfr
- fps=30 filter












Has anyone encountered a similar issue or know how to force FFmpeg to preserve the correct playback speed while encoding or enforcing a frame rate ? Thanks !


- CMD 2 :