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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 (...)

  • Multilang : améliorer l’interface pour les blocs multilingues

    18 février 2011, par

    Multilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
    Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela.

  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
    The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
    For older browsers the Flowplayer flash fallback is used.
    MediaSPIP allows for media playback on major mobile platforms with the above (...)

Sur d’autres sites (7675)

  • Change keyframe interval losslessly to produce mpeg-dash content

    25 mars 2023, par Eeel

    I have a case where i have a mkv file encoded to a 2.5 GB file with x264/CRF settings, in this file group of pictures are not of equal duration (i.e 2,4 or 6 seconds ...).

    


    Now i want to create a mpeg-dash version of the file by extracting the video track to mp4 and set the keyframe interval to 2sec losslessly preserving size (minus other audio and subtitle tracks)

    


    What i already have that work :

    


    Fix keyframe to 2s with x264 :

    


    -codec:v libx264 -force_key_frames 'expr:gte(t,n_forced*2)' -movflags faststart


    


    But it require also encoding settings that change the quality :

    


    -b:v 3500k -maxrate 6000k -bufsize 3500k


    


    In this case i don't need to change the quality from CRF encoding, just change keyframe interval and set faststart flag.

    


    note :
I have detailed bitrate informations about the file obtained by parsing output of ffprobe : average, min and max bitrate in kb/s.
Please avoid solution using -crf 0, mpeg-dash files are later crypted using MP4Box that crash with CRF encoded files.

    


    How can i do this using ffmpeg ?

    


    Edit :

    


    Sorry my question is not clear, i'm fine with re-encode, i want to preserve quality as much as possible.

    


    Using a little more than source mean bitrate for the -b:v parameter the resulting file size is almost same as source, metric test results are not as good i expect :

    


    PSNR 41.03 (expected 44+)
VMAF 76.32 (expected 92+)


    


    Is my bitrate approch good ? Is there anything i can try to improve metric results ?

    


  • avformat/dashdec.c : Download dash content with byte range info

    21 janvier 2018, par Colin NG
    avformat/dashdec.c : Download dash content with byte range info
    • [DH] libavformat/dashdec.c

  • fate/vpx : make webm dash manifest tests depend on the WEBM_DASH_MANIFEST demuxer

    29 août 2014, par Michael Niedermayer
    fate/vpx : make webm dash manifest tests depend on the WEBM_DASH_MANIFEST demuxer

    Found-by : James Almer <jamrial@gmail.com>
    
Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
    • [DH] tests/fate/vpx.mak

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