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  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Creating farms of unique websites

    13 avril 2011, par

    MediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
    This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...)

  • 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

Sur d’autres sites (6901)

  • FFMPEG Dash with tiles of thumbnail images

    31 juillet 2020, par martyn Gilbert

    As of DASH-IF IOP version 4.2, section 6.2.6 defines the notion of image-based tracks in DASH :
https://dashif.org/docs/DASH-IF-IOP-v4.3.pdf.

    



    This is the ability to have an adaption set made up of mime type images that themselves are a strip of low resolution thumbnails. 
A player will use these thumbnails when the user hovers their mouse over the video timeline and get a 
preview of the the frame at that approximate timecode.

    



    Theo player website has a page dedicated to this function for playback :
https://www.theoplayer.com/blog/in-stream-thumbnail-support-dvr-dash-streams

    



    I need to generate a dash stream (not live) using ffmpeg that also contains these thumbnails. 
I already have an ffmpeg command that will generate the film strip of jpgs which outputs a thumbnail every 5 seconds of input video and joins 5 of these together in a single jpg :

    



    ffmpeg -i INPUT -q:v 20 -vf "select=not(mod(n\,125)),scale=480:270,tile=5x1" -vsync vfr output%d.jpg

    



    and the mpeg dash itself :

    



    ffmpeg -i INPUT -y -map 0 -acodec aac -ac 2 -ar 48000 -s 960x540 -vcodec libx264 -f dash -preset veryfast -b:v:2 1500k -seg_duration 2 output.mpd

    



    But I cannot find a way in ffmpeg to include the thumbnails in the dash mpd file.

    


  • MPEG DASH : frame seeking

    13 août 2014, par bisc8

    TL ;DR : Is it possible to achieve frame seeking using DASH ? How ?

    I’m using ffmpeg to create non-multiplexed content :

    ffmpeg -y -an -codec:v libx264 -profile:v baseline output_video.mp4 -i video.mp4
    ffmpeg -y -vn -codec:a libvo_aacenc -ac 1 -ar 44100 output_audio.mp4 -i video.mp4

    Then I’m using mp4box to create DASH content :

    mp4box -dash 10000 -frag 1000 -rap -dash-profile live -segment-name mp4-live-$RepresentationID$-$Number$ -out manifest.mpd output_video.mp4 output_audio.mp4

    Finally I open the generated content with Chrome, using dash.js. Everything works fine except that I can’t do frame seek. I keep on adding (1/frame_rate) seconds to the current time but nothing happens, the frame only changes after 10 seconds.

    I suppose this has to do with the video’s key interval. However, I am able to do frame seek after the ffmpeg part, so I guess I’m missing something in the mp4box command.

    Is it possible to achieve frame seeking using DASH or am I missing something ?

    Thanks in advance.

  • HLS to MPEG DASH

    15 avril 2018, par Maximilian

    Im currently working on a platform that relies on MPEG Dash to deliver audio and video to the browser.
    For onDemand im using ffmpeg to encode videos to h264/aac and MP4Box to create the manifest.mpd file.
    Now im trying to figure out how to create live MPEG Dash streams, more specifically encode hls live streams to MPEG Dash.

    1. Do i need to reencode all the .ts segments to .mp4(h264/aac) segments, since chrome doesnt support mpeg2ts ?
    2. If so, how do i continuously reencode all the segments (different resolution, different bitrates)
    3. How do i create a dynamic manifest with MP4Box / how would the input parameter look like