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  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • Personnaliser les catégories

    21 juin 2013, par

    Formulaire de création d’une catégorie
    Pour ceux qui connaissent bien SPIP, une catégorie peut être assimilée à une rubrique.
    Dans le cas d’un document de type catégorie, les champs proposés par défaut sont : Texte
    On peut modifier ce formulaire dans la partie :
    Administration > Configuration des masques de formulaire.
    Dans le cas d’un document de type média, les champs non affichés par défaut sont : Descriptif rapide
    Par ailleurs, c’est dans cette partie configuration qu’on peut indiquer le (...)

  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

Sur d’autres sites (9990)

  • FFmpeg cannot recognize a preset even though it does exsist Ubuntu 12.04

    31 août 2016, par Ahmad Tahboub

    I have installed ffmpeg and x264 folloowing the steps in this documentation :http://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide

    Now I have this line to execute :

    sudo /usr/bin/ffmpeg -i input_file.flv -f flv -vcodec libx264 -vpre normal -r 25 -s 0x0 -aspect 1.7777777777778 -padcolor 000000 -padtop 0 -padbottom 0 -padleft 0 -padright 0 -acodec libfaac -ab 128000 -ar 22050 output_file.flv

    Input #0, flv, from 'WIN! Jwow.flv':
     Metadata:
       starttime       : 0
       totalduration   : 101
       totaldatarate   : 865
       bytelength      : 10897460
       canseekontime   : true
       sourcedata      : BD58B2E43HH1338284027987695
       purl            :
       pmsg            :
     Duration: 00:01:40.66, start: 0.000000, bitrate: 877 kb/s
       Stream #0.0: Video: h264 (Main), yuv420p, 640x360, 745 kb/s, 29.97 tbr, 1k tbn, 59.94 tbc
       Stream #0.1: Audio: aac, 44100 Hz, stereo, s16, 131 kb/s
    **File for preset 'normal' not found**

    I have the presets in the the following directories :

    /usr/share/ffmpeg
    /usr/local/share/ffmpeg
    /home/user/.ffmpeg
    /usr/local/src/ffmpeg/presets

    And still getting the same error : File for preset ’normal’ not found

    What is the problem here, Please Help !

    Extra info - this is what i get when i do ffmpeg -version

    ffmpeg version git-2012-05-31-60de761
    built on May 31 2012 15:54:11 with gcc 4.6.3
    configuration: --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-nonfree --enable-version3 --enable-x11grab

    Thanks !

  • RAR Is Still A Contender

    31 mai 2012, par Multimedia Mike — Science Projects, bzip2, compression, gzip, lossless, rar, xz

    RAR (Roshal ARchive) is still a popular format in some corners of the internet. In fact, I procured a set of nearly 1500 RAR files that I want to use in a little project. But I didn’t want my program to have to operate directly on the RAR files which meant that I would need to recompress them to another format. Surely, one of the usual lossless compressors commonplace with Linux these days would perform better. Probably not gzip. Maybe not bzip2 either. Perhaps xz, though ?

    Conclusion
    At first, I concluded that xz beat RAR on every single file in the corpus. But then I studied the comparison again and realized it wasn’t quite apples to apples. So I designed a new experiment.

    New conclusion : RAR still beats xz on every sample in this corpus (for the record, the data could be described as executable program data mixed with reduced quality PCM audio samples).

    Methodology
    My experiment involved first reprocessing the archive files into a new resource archive file format and only compressing that file (rather than a set of files) using gzip, bzip2, xz, and rar at the maximum compression settings.

    echo filesize,gzip,bzip2,xz,rar,filename > compressed-sizes.csv
    for f in `ls /path/to/files/*`
    do
      gzip -9 —stdout $f > out.gz
      bzip2 -9 —stdout $f > out.bz2
      xz -9 —stdout —check=crc32 $f > out.xz
      rar a -m5 out.rar $f
      stat —printf "%s," $f out.gz out.bz2 out.rar out.xz >> compressed-sizes.csv
      echo $f >> compressed-sizes.csv
      rm -f out.gz out.bz2 out.xz out.rar
    done
    

    Note that xz gets the option '--check=crc32' since I’m using the XZ Embedded library which requires it. It really doesn’t make a huge different in filesize.

    Experimental Results
    The preceding command line generates compressed-sizes.csv which goes into a Google Spreadsheet (export as CSV).

    Here are the full results of the bake-off, graphed :



    That’s not especially useful. Here are the top 2 contenders compared directly :



    Action
    Obviously, I’m unmoved by the data. There is no way I’m leaving these files in their RAR form for this project, marginal space and bandwidth savings be darned. There are other trade-offs in play here. I know there is free source code available for decompressing RAR files but the license wouldn’t mesh well with GPL source code libraries that form the core of the same project. Plus, the XZ Embedded code is already integrated and painstakingly debugged.

    During this little exercise, I learned of a little site called Maximum Compression which takes experiments like the foregoing to their logical conclusion by comparing over 200 compression programs on a standard data corpus. According to the site’s summary page, there’s a library called PAQ8PX which posts the best overall scores.

  • Is there a way to calculate a average bitrate of video stream for each second ? Using ffmpeg or gsteamer toolkits [closed]

    15 mai 2012, par IOException

    I've encoded some video sample by different x264 presets. I already gathered some metric for each preset's file sample (PSNR,SSIM http://en.wikipedia.org/wiki/Structural_similarity)
    Now I am curious in instant (every seconds) file sample's bitrate, to compare them.

    I found out simple solution by googling around :

    http://akuvian.org/src/mplayer/avi_bitrate.pl
    This works on AVI files (regardless of codec), so you'd have to remux it first.
    Requires perl, mplayer, and gnuplot.

    I works for me