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  • Submit enhancements and plugins

    13 avril 2011

    If you have developed a new extension to add one or more useful features to MediaSPIP, let us know and its integration into the core MedisSPIP functionality will be considered.
    You can use the development discussion list to request for help with creating a plugin. As MediaSPIP is based on SPIP - or you can use the SPIP discussion list SPIP-Zone.

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

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  • ffmpeg change framerate : Question about bitrate [closed]

    9 février, par schweigerson

    Thanks to the forum, I successfully can reduce the frame rate of a video.

    


    ffmpeg -i input_50fps.mp4 -filter:v fps=25 output_25fps.mp4

    


    Input and output have a similar bitrate as well as filzesize :

    


    




    


    


    


    


    


    



    


    


    


    


    


    


    


    


    


    


    File bitrate filesize
    input_50fps.mp4 2900kBit/s 1.9GB
    output_25fps.mp4 2528kBit/s 1.7GB

    


    Assumption : Divide the number of frames into half should both reduce the bitrate and the filesize accordingly (half the size).

    


    Question : Does it make sense to enforce the reduction of the bitrate to approx. half the original one, when I reduce the framerate by to 50% (e.g. with -b:v 1500k) ? IMHO, the video quality should be comparable to the original video then.

    


    Note : I may make according test runs, but I perhaps do not have the ability to recognize the quality difference as I'm not an advanced video expert.

    


    Would be happy to read your advice.

    


  • FFMPEG - RADEON - VAAPI - Alfa channel overlay

    25 janvier, par Alexandre Leitão

    Ok I got to my limit so decided to ask for help. I'm running a python app in a docker container. It works fine with VAAPI and hardware acceleration(AMD Radeon GPU) till I use filter complex. This is my command

    


    ffmpeg -v error -y -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -stream_loop -1 -f concat -i video_list.txt -stream_loop -1 -f concat -i overlay_list1.txt -stream_loop -1 -f concat -i overlay_list.txt -filter_complex "[0:v][1:v]overlay=x=0:y=0:shortest=1[out];[out][2:v]overlay=x=0:y=0:shortest=1[out1]" -map "[out1]" -map 1:a -c:v h264_vaapi -c:a aac -b:a 192k -t 1800 text.mp4


    


    video_list.txt contains 2 mp4 videos h264 (30sec each)
overlay_list1.txt contains 2 mov video (alfa channel overlays 2 minutes each)
overlay_list.txt contains 1 mov video (alfa channel overlay 25 minutes long)

    


      

    • the idea is loop video_list.txt to -t (1800 at the moment)

      • 


    • Loop overlay_list1.txt over it till -t

      • 


    • and loop overlay.txt above everything

      • 


    


    Audio only comes from overlay_list1.txt videos
What I get is this output

    


    Impossible to convert between the formats supported by the filter 'Parsed_overlay_1' and the filter 'auto_scale_2'
[fc#0 @ 0x5fadddb56540] Error reinitializing filters!
[fc#0 @ 0x5fadddb56540] Task finished with error code: -38 (Function not implemented)
[fc#0 @ 0x5fadddb56540] Terminating thread with return code -38 (Function not implemented)
[vost#0:0/h264_vaapi @ 0x5fadddb3f400] Could not open encoder before EOF
[vost#0:0/h264_vaapi @ 0x5fadddb3f400] Task finished with error code: -22 (Invalid argument)
[vost#0:0/h264_vaapi @ 0x5fadddb3f400] Terminating thread with return code -22 (Invalid argument)
[out#0/mp4 @ 0x5fadddc3f140] Nothing was written into output file, because at least one of its streams received no packets.


    


    I tried everything and couldn't fix... the last thing I read is I suppose to use hwupload and hwdownload on filter complex but I couldn't understand how to do it.

    


    Any help is welcome guys
thank you and happy new year to y'all

    


  • avcodec/vvcdec : fix potential deadlock in report_frame_progress

    25 août 2024, par Nuo Mi
    avcodec/vvcdec : fix potential deadlock in report_frame_progress

    Fixes :
    
https://fate.ffmpeg.org/report.cgi?slot=x86_64-archlinux-gcc-tsan&time=20240823175808
    

    Reproduction steps :
    
./configure —enable-memory-poisoning —toolchain=gcc-tsan —disable-stripping && make fate-vvc
    

    Root cause :
    
We hold the current frame's lock while updating progress for other frames,
    
which also requires acquiring other frame locks. This could potentially lead to a deadlock.
    
However, I don't think this will happen in practice because progress updates are one-way, with no cyclic dependencies.
    
But we need this patch to make FATE happy.
    • [DH] libavcodec/vvc/refs.c
    • [DH] libavcodec/vvc/thread.c

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