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Configurer la prise en compte des langues
15 novembre 2010, parAccéder à la configuration et ajouter des langues prises en compte
Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...) -
Support de tous types de médias
10 avril 2011Contrairement à beaucoup de logiciels et autres plate-formes modernes de partage de documents, MediaSPIP a l’ambition de gérer un maximum de formats de documents différents qu’ils soient de type : images (png, gif, jpg, bmp et autres...) ; audio (MP3, Ogg, Wav et autres...) ; vidéo (Avi, MP4, Ogv, mpg, mov, wmv et autres...) ; contenu textuel, code ou autres (open office, microsoft office (tableur, présentation), web (html, css), LaTeX, Google Earth) (...)
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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" ;
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FFMPEG and AWS : What's the most efficient way to handle this ?
28 mai 2022, par Red VicI'm new to AWS and I originally built the FFmpeg functions on my Node.JS API. But I realized this is the wrong way to do it in a real-world app, and that you need to use separate Lambda functions in AWS that handle the video editing separately from the main server.


I'm mainly a front-end developer but I'm open to learning new things.


I basically have the following process in my app :


- 

- User uploads video.
- I need to take that video and add a watermark to it.
- I then need a copy of the watermarked video in a smaller resolution.
- I then need a 6 seconds GIF of the smaller resolution video.
- Finally, I need to upload the 3 edited files (2 .mp4's and 1 .gif) to S3, and remove the original, non-watermarked video.












Here are my questions to be clear :


- 

- Should I upload the original file to S3 or to the server ? And why ?
- Is the process above doable in a single Lambda function ? Or do I need more Lambda functions ?
- How would you handle this problem, personally ?








I originally built it by chaining one function to the next with promises, but AWS seems like a different world of doing things and the way I originally built it would not work.


Thanks a lot.


Update
Here are some tests I did with a couple videos :







 

Test 1 

Test 2 

Test 3 

Test 4 

Test 5 







 Original video resolution 

1080p 

1080p 

1080p 

1080p 

480p 




 Original video duration 

23 minutes 

15 minutes 

11 minutes 

3.5 minutes 

5 minutes 




 Step 1 duration (Watermarking original video) 

30 minutes 

18 minutes 

14 minutes 

4 minutes 

2 minutes 




 Step 2 duration (Watermarking lower resolution) 

5 minutes 

3 minutes 

3 minutes 

1 minute 

skip (already low res) 




 Step 3 duration (6 seconds GIF creation) 

negligible (15 seconds) 

negligible (10 seconds) 

negligible (7 seconds) 

negligible 

negligible 




 Total 

35 minutes 

21 minutes 

17 minutes 

5 minutes 

2 minutes 







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lavfi/nlmeans : make compute_safe_ssd_integral_image_c faster
6 mai 2018, par Clément Bœschlavfi/nlmeans : make compute_safe_ssd_integral_image_c faster
before : ssd_integral_image_c : 49204.6
after : ssd_integral_image_c : 44272.8Unrolling by 4 made the biggest difference on odroid-c2 (aarch64) ;
unrolling by 2 or 8 both raised 46k cycles vs 44k for 4.Additionally, this is a much better reference when writing SIMD (SIMD
vectorization will just target 16 instead of 4). -
hardware conversion of image pixel format in ffmpeg ?
18 janvier 2024, par dongrixinyuI am trying to decode an online rtmp video stream into RGB format frames, and then encoding RGB frames into an online stream.


Task


Here is what I do now :




decoding a video stream to get images(RGB) ---> ai model process ---> encoding frames(RGB) to form a video stream in H264




My scheme


All my code in written in C with FFmpeg dependencies. The detailed steps are :




rtmp/rtsp video stream --->
AVPacket
---(nvidia cuda)--->AVFrame
(nv12 pix fmt) --->AVFrame
(RGB pix fmt) ---> AI process.





AVFrame
(RGB pix fmt) --->AVFrame
(nv12 pix fmt) ---(nvidia cuda)--->AVPacket
---> rtmp/rtsp video stream



Now, the decoding and encoding part are run on NVIDIA GPU, which is quite fast.


But the conversion of pixel format between
AV_PIX_FMT_NV12
andAV_PIX_FMT_RGB
is run on CPU, which is astonishingly CPU-consuming cause the size of video frame is 2k.

My question


So, is there any off-the-shelf method to fulfill the conversion of image pixel format on GPU (especially via cuda) directly ?