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  • Demande de création d’un canal

    12 mars 2010, par

    En fonction de la configuration de la plateforme, l’utilisateur peu avoir à sa disposition deux méthodes différentes de demande de création de canal. La première est au moment de son inscription, la seconde, après son inscription en remplissant un formulaire de demande.
    Les deux manières demandent les mêmes choses fonctionnent à peu près de la même manière, le futur utilisateur doit remplir une série de champ de formulaire permettant tout d’abord aux administrateurs d’avoir des informations quant à (...)

  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 is the first MediaSPIP stable release.
    Its official release date is June 21, 2013 and is announced here.
    The zip file provided here only contains the sources of MediaSPIP in its standalone version.
    To get a working installation, you must manually install all-software dependencies on the server.
    If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)

  • Mediabox : ouvrir les images dans l’espace maximal pour l’utilisateur

    8 février 2011, par

    La visualisation des images est restreinte par la largeur accordée par le design du site (dépendant du thème utilisé). Elles sont donc visibles sous un format réduit. Afin de profiter de l’ensemble de la place disponible sur l’écran de l’utilisateur, il est possible d’ajouter une fonctionnalité d’affichage de l’image dans une boite multimedia apparaissant au dessus du reste du contenu.
    Pour ce faire il est nécessaire d’installer le plugin "Mediabox".
    Configuration de la boite multimédia
    Dès (...)

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  • Is there an efficient way to use ffmpeg to perform a large quantity of cuts from a single file ?

    16 mars 2024, par Giuliano Oliveri

    I'm trying to cut video files into smaller chunks. (each one being one word said in the video, so they're not all of equal size)

    


    I've tried a lot of different approaches to try to be as efficient as possible, but I can't get the runtime to be under 2/3rd of the original video length. That's an issue because I'm trying to process 400+ hours of video.

    


    Is there a more efficient way to do this ? Or am I doomed to run this for weeks ?

    


    Here is the command for my best attempt so far

    


    ffmpeg -hwaccel cuda -hwaccel_output_format cuda -ss start_timestamp -t to_timestamp -i file_name -vf "fps=30,scale_cuda=1280:720" -c:v h264_nvenc -y output_file


    


    Note that the machine running the code has a 4090
This command is then executed via python, which gives it the right timestamps and file paths for each smaller clip in a for loop

    


    I think it's wasting a lot of time calling a new process each time, however I haven't been able to get better results with a split filter ; but here's the ffmpeg-python code for that attempt :

    


    Creation of the stream :

    


    inp = (
    ffmpeg
    .input(file_name, hwaccel="cuda", hwaccel_output_format="cuda")
    .filter("fps",fps=30)
    .filter('scale_cuda', '1280','720')
    .filter_multi_output('split')
)


    


    Which then gets called in a for loop

    


    (
    ffmpeg
    .filter(inp, 'trim', start=row[1]['start'], end=row[1]['end'])
    .filter('setpts', 'PTS-STARTPTS')
    .output(output_file,vcodec='h264_nvenc')
    .run()
)


    


  • Is there an efficient way to use ffmpeg to create a huge quantity of small video file, cut from a larger one ?

    9 mars 2024, par Giuliano Oliveri

    I'm trying to cut video files into smaller chunks. (each one being one word said in the video, so they're not all of equal size)

    


    I've tried a lot of different approaches to try to be as efficient as possible, but I can't get the runtime to be under 2/3rd of the original video length. That's an issue because I'm trying to process 400+ hours of video.

    


    Is there a more efficient way to do this ? Or am I doomed to run this for weeks ?

    


    Here is the command for my best attempt so far

    


    ffmpeg -hwaccel cuda -hwaccel_output_format cuda -ss start_timestamp -t to_timestamp -i file_name -vf "fps=30,scale_cuda=1280:720" -c:v h264_nvenc -y output_file


    


    Note that the machine running the code has a 4090
This command is then executed via python, which gives it the right timestamps and file paths for each smaller clip in a for loop

    


    I think it's wasting a lot of time calling a new process each time, however I haven't been able to get better results with a split filter ; but here's the ffmpeg-python code for that attempt :

    


    Creation of the stream :

    


    inp = (
    ffmpeg
    .input(file_name, hwaccel="cuda", hwaccel_output_format="cuda")
    .filter("fps",fps=30)
    .filter('scale_cuda', '1280','720')
    .filter_multi_output('split')
)


    


    Which then gets called in a for loop

    


    (
    ffmpeg
    .filter(inp, 'trim', start=row[1]['start'], end=row[1]['end'])
    .filter('setpts', 'PTS-STARTPTS')
    .output(output_file,vcodec='h264_nvenc')
    .run()
)


    


  • swresample/resample : do not increase phase_count on exact_rational

    17 juin 2016, par Muhammad Faiz
    swresample/resample : do not increase phase_count on exact_rational

    high phase_count is only useful when dst_incr_mod is non zero
    
in other word, it is only useful on soft compensation
    

    on init, it will build filter with low phase_count
    
but when soft compensation is enabled, rebuild filter
    
with high phase_count
    

    this approach saves lots of memory
    

    Reviewed-by : Michael Niedermayer <michael@niedermayer.cc>
    
Signed-off-by : Muhammad Faiz <mfcc64@gmail.com>
    • [DH] libswresample/resample.c
    • [DH] libswresample/resample.h

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