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  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 est la première version de MediaSPIP stable.
    Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

  • Le profil des utilisateurs

    12 avril 2011, par

    Chaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
    L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...)

  • MediaSPIP version 0.1 Beta

    16 avril 2011, par

    MediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

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  • Issue installing OpenCV 3.0.0 on Ubuntu 14.04

    26 septembre 2015, par marcman

    I’ve been trying to install OpenCV on a Linux machine running Ubuntu 14.04. I’ve installed all of the dependencies that I have come across in tutorials as well as those listed on the OpenCV site. However, I’m pretty new to Linux and the Linux file system, so I wouldn’t be terribly surprised if these issues are related to the installation location or something.

    It appears that I am getting an issue with FFMPEG stuff, but I definitely have it installed

    dpkg -s libgtk2.0-0 | grep '^Version'

    returns

    Version: 2.24.23-0ubuntu1.3

    I’m not quite sure what the issue is here. Below is the error printout. Most of the lines are pretty much identical (I’m assuming the same issue is causing each of these errors). Although I posted the whole thing below for completeness, you can probably get at the issue from one or two of the errors as well as the last line. For brevity’s sake, here are a sample of the errors :

    ...
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:738:67: error: 'PIX_FMT_RGB24' was not declared in this scope
    
     avpicture_fill((AVPicture*)&rgb_picture, rgb_picture.data[0], PIX_FMT_RGB24,
    
                                                                   ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:756:17: error: 'PIX_FMT_BGR24' was not declared in this scope
    
                 PIX_FMT_BGR24,
    
                 ^
    
...
    
[ 35%] Built target opencv_photo
    
make: *** [all] Error 2
    
$

    The commands immediately preceding the errors were

    $ cmake -DWITH_QT=ON -DWITH_OPENGL=ON -DFORCE_VTK=ON -DWITH_TBB=ON -DWITH_GDAL=ON -DWITH_XINE=ON -DBUILD_EXAMPLES=ON ..
    
$ make -j4

    as taken from the tutorial I linked to above.

    Entire error printout :

    In file included from /usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg.cpp:45:0:
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'void CvCapture_FFMPEG::close()':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:317:36: error: 'avcodec_free_frame' was not declared in this scope
    
         avcodec_free_frame(&picture);
    
                                    ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'bool CvCapture_FFMPEG::open(const char*)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:632:43: error: 'avcodec_alloc_frame' was not declared in this scope
    
             picture = avcodec_alloc_frame();
    
                                           ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:635:41: error: 'PIX_FMT_BGR24' was not declared in this scope
    
                     avpicture_get_size( PIX_FMT_BGR24,
    
                                         ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'bool CvCapture_FFMPEG::retrieveFrame(int, unsigned char**, int*, int*, int*, int*)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:738:67: error: 'PIX_FMT_RGB24' was not declared in this scope
    
     avpicture_fill((AVPicture*)&rgb_picture, rgb_picture.data[0], PIX_FMT_RGB24,
    
                                                                   ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:756:17: error: 'PIX_FMT_BGR24' was not declared in this scope
    
                 PIX_FMT_BGR24,
    
                 ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In function 'AVFrame* icv_alloc_picture_FFMPEG(int, int, int, bool)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1110:35: error: 'avcodec_alloc_frame' was not declared in this scope
    
     picture = avcodec_alloc_frame();
    
                                   ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1113:33: error: 'PixelFormat' was not declared in this scope
    
     size = avpicture_get_size( (PixelFormat) pix_fmt, width, height);
    
                                 ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1122:38: error: expected ')' before 'pix_fmt'
    
                        (PixelFormat) pix_fmt, width, height);
    
                                      ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: At global scope:
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1104:18: warning: unused parameter 'pix_fmt' [-Wunused-parameter]
    
 static AVFrame * icv_alloc_picture_FFMPEG(int pix_fmt, int width, int height, bool alloc)
    
                  ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In function 'AVStream* icv_add_video_stream_FFMPEG(AVFormatContext*, AVCodecID, int, int, int, double, int)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1230:19: error: 'PixelFormat' was not declared in this scope
    
     c->pix_fmt = (PixelFormat) pixel_format;
    
                   ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1230:32: error: expected ';' before 'pixel_format'
    
     c->pix_fmt = (PixelFormat) pixel_format;
    
                                ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: At global scope:
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1130:18: warning: unused parameter 'pixel_format' [-Wunused-parameter]
    
 static AVStream *icv_add_video_stream_FFMPEG(AVFormatContext *oc,
    
                  ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'bool CvVideoWriter_FFMPEG::writeFrame(const unsigned char*, int, int, int, int, int)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1405:26: error: 'PIX_FMT_BGR24' was not declared in this scope
    
     if (input_pix_fmt == PIX_FMT_BGR24) {
    
                          ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1410:31: error: 'PIX_FMT_GRAY8' was not declared in this scope
    
     else if (input_pix_fmt == PIX_FMT_GRAY8) {
    
                               ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1423:25: error: 'PixelFormat' was not declared in this scope
    
                        (PixelFormat)input_pix_fmt, width, height);
    
                         ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1429:59: error: expected ')' before 'input_pix_fmt'
    
                                              (PixelFormat)input_pix_fmt,
    
                                                           ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1447:25: error: 'PixelFormat' was not declared in this scope
    
                        (PixelFormat)input_pix_fmt, width, height);
    
                         ^
    
In file included from /usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg.cpp:45:0:
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'bool CvVideoWriter_FFMPEG::open(const char*, int, double, int, int, bool)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1604:25: error: 'PIX_FMT_BGR24' was not declared in this scope
    
         input_pix_fmt = PIX_FMT_BGR24;
    
                         ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1607:25: error: 'PIX_FMT_GRAY8' was not declared in this scope
    
         input_pix_fmt = PIX_FMT_GRAY8;
    
                         ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1683:25: error: 'PIX_FMT_YUV422P' was not declared in this scope
    
         codec_pix_fmt = PIX_FMT_YUV422P;
    
                         ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1687:25: error: 'PIX_FMT_YUVJ420P' was not declared in this scope
    
         codec_pix_fmt = PIX_FMT_YUVJ420P;
    
                         ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1691:42: error: 'PIX_FMT_GRAY8' was not declared in this scope
    
         codec_pix_fmt = input_pix_fmt == PIX_FMT_GRAY8 ||
    
                                          ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1692:42: error: 'PIX_FMT_GRAY16LE' was not declared in this scope
    
                         input_pix_fmt == PIX_FMT_GRAY16LE ||
    
                                          ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1693:42: error: 'PIX_FMT_GRAY16BE' was not declared in this scope
    
                         input_pix_fmt == PIX_FMT_GRAY16BE ? input_pix_fmt : PIX_FMT_YUV420P;
    
                                          ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1693:77: error: 'PIX_FMT_YUV420P' was not declared in this scope
    
                         input_pix_fmt == PIX_FMT_GRAY16BE ? input_pix_fmt : PIX_FMT_YUV420P;
    
                                                                             ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: At global scope:
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1922:119: error: 'PixelFormat' has not been declared
    
     static AVStream* addVideoStream(AVFormatContext *oc, CV_CODEC_ID codec_id, int w, int h, int bitrate, double fps, PixelFormat pixel_format);
    
                                                                                                                       ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:1969:134: error: 'PixelFormat' has not been declared
    
 AVStream* OutputMediaStream_FFMPEG::addVideoStream(AVFormatContext *oc, CV_CODEC_ID codec_id, int w, int h, int bitrate, double fps, PixelFormat pixel_format)
    
                                                                                                                                      ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In static member function 'static AVStream* OutputMediaStream_FFMPEG::addVideoStream(AVFormatContext*, AVCodecID, int, int, int, double, int)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2047:16: error: invalid conversion from 'int' to 'AVPixelFormat' [-fpermissive]
    
     c->pix_fmt = pixel_format;
    
                ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'bool OutputMediaStream_FFMPEG::open(const char*, int, int, double)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2107:5: error: 'PixelFormat' was not declared in this scope
    
     PixelFormat codec_pix_fmt = PIX_FMT_YUV420P;
    
     ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2107:17: error: expected ';' before 'codec_pix_fmt'
    
     PixelFormat codec_pix_fmt = PIX_FMT_YUV420P;
    
                 ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2111:99: error: 'codec_pix_fmt' was not declared in this scope
    
     video_st_ = addVideoStream(oc_, codec_id, width, height, width * height * bitrate_scale, fps, codec_pix_fmt);
    
                                                                                                   ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp: In member function 'bool InputMediaStream_FFMPEG::open(const char*, int*, int*, int*, int*)':
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2316:18: error: 'PIX_FMT_YUV420P' was not declared in this scope
    
             case PIX_FMT_YUV420P:
    
                  ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2320:18: error: 'PIX_FMT_YUV422P' was not declared in this scope
    
             case PIX_FMT_YUV422P:
    
                  ^
    
/usr/opencv-3.0.0/modules/videoio/src/cap_ffmpeg_impl.hpp:2324:18: error: 'PIX_FMT_YUV444P' was not declared in this scope
    
             case PIX_FMT_YUV444P:
    
                  ^
    
make[2]: *** [modules/videoio/CMakeFiles/opencv_videoio.dir/src/cap_ffmpeg.cpp.o] Error 1
    
make[2]: *** Waiting for unfinished jobs....
    
[ 35%] Building CXX object modules/photo/CMakeFiles/opencv_photo.dir/src/align.cpp.o
    
make[1]: *** [modules/videoio/CMakeFiles/opencv_videoio.dir/all] Error 2
    
make[1]: *** Waiting for unfinished jobs....
    
[ 35%] Building CXX object modules/photo/CMakeFiles/opencv_photo.dir/src/seamless_cloning_impl.cpp.o
    
[ 35%] Building CXX object modules/photo/CMakeFiles/opencv_photo.dir/src/hdr_common.cpp.o
    
[ 35%] Building CXX object modules/photo/CMakeFiles/opencv_photo.dir/opencl_kernels_photo.cpp.o
    
Linking CXX shared library ../../lib/libopencv_photo.so
    
[ 35%] Built target opencv_photo
    
make: *** [all] Error 2

    Any insight is greatly appreciated !

  • GOP size does not correlate with actual latency

    28 mai 2019, par Alex

    As far as I know, GOP size should correlate with observable video delay (latency). For example, if GOP size is 2, then delay in video should be near two seconds and so on, at least with CBR. But, when I set GOP size to 2, publish stream to ingest server, consume this stream and measure latency, it is between 0.8-1.2 seconds, not 2+ seconds as excepted. Increasing GOP size leads to same results : with GOP 4 latency is near 2.5 seconds, not 4 seconds.

    How I measure this latency : stream working stopwatch from web-camera using OBS to ingest server and calculate difference between stopwatch value and value displayed in stream consumed from ingest. For greater measurement accuracy, I make a photo with stopwatch and actual image from ingest in one field of view.

    My OBS settings is here :

    enter image description here

    Can you suggest, why do I get such results and how relevant is my statement about correlation between GOP size and video latency ? Maybe, H264 settings like "zerolatency" makes some magic ?

    Thanks.

  • How can I transform a sequence of images into a playable video using LibVLCSharp ?

    9 février 2021, par adamasan

    I have a sequence of images that I was able to extract from a video using LibVLCSharp. This sample to be more specific. I'm creating a small video library manager for learning purposes, and I would like to extract frames and create thumbnails to play when the user hovers the mouse over the previewer.

    


    Using the aforementioned sample I was able to create a WPF UI around the same loging and extract the frames from a video file. However what I want now is to convert these extracted frames into a video file, using them as preview for the video, just like happens on YouTube.

    


    I wasn't able, however, to find out how to achieve this using LibVLCSharp or just LibVLC. Using this answer on Super User I was able to achieve my goal and put those frames together into a video using ffmpeg.

    


    I haven't taken the time yet to study FFmpeg.Autogen, so I don't know if I would be able to extract the frames from the video files in the same way I can do with LibVLCSharp, but I don't see with good eyes using both libraries on my application, one to export the frames and one to generate these frames into a video.

    


    So, is there a way to get the output frames and convert them into a playable video using LibVLCSharp (or libvlc) itself ?

    


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