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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 (...)

  • 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 (...)

  • ANNEXE : Les plugins utilisés spécifiquement pour la ferme

    5 mars 2010, par

    Le site central/maître de la ferme a besoin d’utiliser plusieurs plugins supplémentaires vis à vis des canaux pour son bon fonctionnement. le plugin Gestion de la mutualisation ; le plugin inscription3 pour gérer les inscriptions et les demandes de création d’instance de mutualisation dès l’inscription des utilisateurs ; le plugin verifier qui fournit une API de vérification des champs (utilisé par inscription3) ; le plugin champs extras v2 nécessité par inscription3 (...)

Sur d’autres sites (7101)

  • Revision 047b0b01bb : Fix show existing frame - Disable mode info update in case where current frame

    5 décembre 2013, par Tero Rintaluoma

    Changed Paths :
     Modify /vp9/common/vp9_onyxc_int.h


     Modify /vp9/decoder/vp9_decodeframe.c


     Modify /vp9/decoder/vp9_onyxd_if.c



    Fix show existing frame

    - Disable mode info update in case where current frame is coded
    as "show existing frame".
    - Should fix issue 676.

    Change-Id : Ibee681850eb307f982da6528d3e31cb94f881c08

  • How correctly show video with transparency in Qt with OpenCV + FFMpeg

    11 avril 2022, par TheEnigmist

    I'm trying to show a video with transparency in a Qt6 application using OpenCV + FFMPEG.
Actually those are tool versions :

    


      

    • Win 11

      • 


    • Qt 6.3.0

      • 


    • OpenCV 4.5.5 (built with CMake)

      • 


    • FFMPEG 2022-04-03-git-1291568c98-full_build-www.gyan.dev

      • 


    


    I've used a base .mov video with transparency as test (link provided below).
First of all I've converted .mov video to .webm video (VP9) and I see in output text that alpha channel remains

    


    


    ffmpeg -i '.\Retro Bars.mov' -c:v libvpx-vp9 -crf 30 -b:v 0 output.webm

    


    


    Input #0, mov,mp4,m4a,3gp,3g2,mj2,
    ...
    Stream #0:0[0x1](eng): Video: qtrle (rle  / 0x20656C72), argb(progressive),
    ...

Output #0, webm, 
   ...
   Stream #0:0(eng): Video: vp9, yuva420p(tv, progressive),
   ...


    


    But when I show info of output file with ffmpeg it loses alpha channel :

    


    


    ffmpeg -i .\output.webm

    


    


    Input #0, matroska,webm,
    ...
    Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv, progressive),
    ...


    


    If I open output.webm with OBS it is shown correctly without a background, as shown in picture :
obs_load

    


    If I try to open it with OpenCV + FFMPEG it shows a black background under bars, as shown in picture :
Qt_out

    


    This is how I load video in Qt :

    


    cv::VideoCapture capture;
capture.open(filename, cv::CAP_FFMPEG);
capture.set(cv::CAP_PROP_CONVERT_RGB, false); // try forcing load alpha channel
... //in a thread
while (capture.read(frame)) {
    qDebug() << "c" << frame.channels() << "t" <<  frame.type() << "d" <<  frame.depth(); // output: c 3 t 16 d 0
    cv::cvtColor(frame, frame, cv::COLOR_BGR2RGBA); //useless since no alpha channel is detected
    img = QImage(frame.data, frame.cols, frame.rows, QImage::Format_RGBA8888);
    emit processedImage(img); // to show image in a QLabel with QPixmap::fromImage(img)
}


    


    I think the problem is when I load the video with OpenCV, it doens't detect alpha channel, since I can load correctly in other player (obs, html5, etc.)

    


    What I'm wrong with all process to show this video in Qt with transparency ?

    


    EDIT : Added dropbox link with test video + ffmpeg outputs :
sample items

    


  • lavfi/overlay : show incoming frames on debug messages

    20 juin 2014, par Stefano Sabatini
    lavfi/overlay : show incoming frames on debug messages

    This is especially useful to debug queue overflow issues.
    

    Ideally we should be able to set the debug message at the
    
dualinput/framesync level, but they do not have the information related
    
to the filter context and the inlink, so cannot access much useful
    
information.
    

    Signed-off-by : Stefano Sabatini <stefasab@gmail.com>
    • [DH] libavfilter/vf_overlay.c

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