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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

  • 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

  • Support audio et vidéo HTML5

    10 avril 2011

    MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
    Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
    Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
    Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...)

Sur d’autres sites (6240)

  • FFMPEG : extracting jpegs at 1 fps rate with "-r 1" or "vf fps=fps=1" causes first three frames to be wrong [closed]

    11 avril 2013, par Stefan

    I need to use ffmpeg to extract video stills from a video, one picture per second, starting with second 0. I created a 4min test video with a running timecode (25fps, starting with 00:00:00 running to 03:59:24) If I use either

    ffmpeg -i input.mp4 -f image2 -r 1 still-%d.jpeg

    or

    ffmpeg -i input.mp4 -f image2 -vf fps="fps=1" still-%d.jpeg

    I fail because the first three images do not display expected time codes 00:00:00, 00:01:00, 00:02:00, but 00:00:00, 00:00:01, 00:00:13, and all subsequent images show having frame 13 in their timecode (and not :00). This causes my video preview to be off by 1-2 seconds.

    I had to resort to invoke ffmpeg for each frame, using -ss 0..240 and -vframes 1 to extract exactly one frame at the exact time. This works perfectly, all output files show the timecode of the first frame of that second.

    This method is considerably slower, however, and I'd rather not use it.

    Is there something I missed with the -r option or fps filter ? I tried specifying fps=fps=1:round=zero, but I got an error saying that the key "round" was not found.

    Thank you in advance !

  • Failed to capture a avi file using opencv

    30 avril 2017, par Wei

    I am quite new to c++ compilation. I am trying to work on a simple problem using opencv where I read a video file and display it.

    My code looks like :

    #include <opencv></opencv>cv.h>
    #include <opencv></opencv>highgui.h>
    #include "opencv2/opencv.hpp"
    #include <opencv2></opencv2>core/core.hpp>
    #include <opencv2></opencv2>highgui/highgui.hpp>


    #include
    #include

    #include <algorithm>
    #include
    #include
    #include
    #include <fstream>
    #include <iostream>
    #include <vector>
    #include <list>
    #include <string>


    using namespace cv;

    IplImage* image = 0;
    IplImage* prev_image = 0;

    int show = 1;

    int main( int argc, char** argv )
    {
       int frameNum = 0;

       char* video = argv[1];
       VideoCapture capture(video);

       if( !capture.isOpened() ) {
           printf( "Could not initialize capturing..\n" );
           return -1;
       }

       if( show == 1 )
           cvNamedWindow( "Video", 0 );

       while( true ) {
           IplImage* frame = 0;
           int i, j, c;

           // get a new frame
           //frame = cvQueryFrame( capture );
           Mat mat_img;
           capture >> mat_img;
           IplImage frame1 = mat_img.operator IplImage();
           frame = &amp;frame1;
           if( !frame )
               break;

           if( !image ) {
               image =  cvCreateImage( cvSize(frame->width,frame->height), 8, 3 );
               image->origin = frame->origin;
           }

           cvCopy( frame, image, 0 );

           if( show == 1 ) {
               cvShowImage( "Video", image);
               c = cvWaitKey(3);
               if((char)c == 27) break;
           }

           std::cerr &lt;&lt; "The " &lt;&lt; frameNum &lt;&lt; "-th frame" &lt;&lt; std::endl;
           frameNum++;
       }

       if( show == 1 )
           cvDestroyWindow("Video");

       return 0;
    }
    </string></list></vector></iostream></fstream></algorithm>

    Then I compile it like :

    g++ test.cpp -o Video -pipe -D __STDC_CONSTANT_MACROS -D STD=std -Wall -I. -I/usr/local/ -O3 -DNDEBUG -ggdb -L/usr/local/ -lopencv_core -lopencv_highgui -lopencv_video -lopencv_imgproc -lavformat -lavdevice -lavutil -lavcodec -lswscale

    Compilation works fine and no errors returned.

    However, when I was running it, I got :

    (Video:5651): GLib-GObject-CRITICAL **: g_object_set: assertion 'G_IS_OBJECT (object)' failed
    Could not initialize capturing..

    Some other information :
    1. I test my opencv and ffmpeg by running simple examples, which work well.
    2. I can stream frames from my camera and display it using opencv.

    Anyone has idea of what causes this ?

    Any idea is appreciated.

  • FFMPEG interactive Mode help options

    7 février 2018, par Pliny Ida Plisetsky

    While streaming a simple command like below

    ffmpeg -i "Alien.mkv" -f webm tcp://localhost:8080/listen.webm

    if I press ’ ?’ ffmpeg seems to have an interactive mode with the below options

      ?      show this help

      +      increase verbosity

      -      decrease verbosity

      c      Send command to first matching filter supporting it

      C      Send/Queue command to all matching filters

      D      cycle through available debug modes

      h      dump packets/hex press to cycle through the 3 states

      q      quit

      s      Show QP histogram

    I was curious about option ’c’

    Does this mean that I can execute further commands on the running stream ? Say for instance seeking a new position in a running stream ? (I realise you wouldn’t normally do this)

    I don’t really know anything about these and couldn’t find much in the ffmpeg documentation or else where. If I press ’c’ it suggests the syntax I should use is :

    Enter command: <target>|all <time>|-1 <command>[ <argument>]
    </argument></command></time></target>

    but I still don’t really understand how to execute a command. Would someone please give a few examples ? I suspect that this isn’t used much.