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  • MediaSPIP 0.1 Beta version

    25 avril 2011, par

    MediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
    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 (...)

  • Problèmes fréquents

    10 mars 2010, par

    PHP et safe_mode activé
    Une des principales sources de problèmes relève de la configuration de PHP et notamment de l’activation du safe_mode
    La solution consiterait à soit désactiver le safe_mode soit placer le script dans un répertoire accessible par apache pour le site

  • Support de tous types de médias

    10 avril 2011

    Contrairement 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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  • Is it possible to change volume with no reencode with ffmpeg ?

    30 juin 2023, par John Smith

    I just had this question because I used the following command with ffmpeg :

    



    ffmpeg -i input.wav -filter:a "volume=0.2" output.wav


    



    Following the documentation here : https://trac.ffmpeg.org/wiki/AudioVolume

    



    However, when I created the new file, the output was half the size of the input and the bitrate of the audio track was reduced as well.

    



    So my questions are :

    



      

    1. Is the bitrate supposed to decrease with decreasing and increasing volume like so ?

      2. 


    2. Is it possible to change volume without reencoding with ffmpeg ?

      3. 


    


  • Create a looped video with countdown

    13 décembre 2016, par Enrico Deleo

    Something maybe challenging here :
    I want to stream (via rtmp) a video with a fixed image and a countdown applied on it. I know I can create a slideshow with even audio background with ffmtp (http://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images) but I’m wondering if I can loop it AND apply an overlay with the countdown to a given date.

    Any ideas ?

  • encode YUV420 frame to VP9

    21 novembre 2018, par User800222

    As title,

    I’m pulling frames from a IP camera. I converted the input raw data to YUV420 format, and would like to encode YUV420 to VP9, and save frames as .webm format. Would I be able to do that ? Or should I input a BGR444 format for encoding ?

    BTW, to set up the parameters for encoding vp9. Is the av_dict_set() the right function for setting parameters ?

    Ex : (http://wiki.webmproject.org/ffmpeg/vp9-encoding-guide)

    av_dict_set(&opt, "crf"    , "23", 0);
    
av_dict_set(&opt, "speed"  , "4" , 0);
    
av_dict_set(&opt, "threads", "8" , 0);
    
av_dict_set(&opt, "pass"   , "1" , 0);
    
av_dict_set(&opt, "b:v", "1400k", 0);

    Edit : The wiki uses 2 pass for setting parameters, would I be able to do in with 1 pass ?

    Edit2 : Blow code seems to be working, wonder how can I bring the size of the videos (vp9) down ? Currently, I have similar size as using h264 encoder.

        av_dict_set(&opt, "crf"    ,        "45", 0);  
    
    av_dict_set(&opt, "speed"  ,        "8" , 0); 
    
    av_dict_set(&opt, "quality",        "realtime", 0);
    
    av_dict_set(&opt, "threads",        "8" , 0);
    
    av_dict_set(&opt, "tile-columns",   "3", 0);
    
    av_dict_set(&opt, "frame-parallel", "1", 0);
    
    av_dict_set(&opt, "row-mt",         "1", 0);

    Update1 :
    YUV420P can be encoded as VP9 !

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