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  • Les images

    15 mai 2013
  • Taille des images et des logos définissables

    9 février 2011, par

    Dans beaucoup d’endroits du site, logos et images sont redimensionnées pour correspondre aux emplacements définis par les thèmes. L’ensemble des ces tailles pouvant changer d’un thème à un autre peuvent être définies directement dans le thème et éviter ainsi à l’utilisateur de devoir les configurer manuellement après avoir changé l’apparence de son site.
    Ces tailles d’images sont également disponibles dans la configuration spécifique de MediaSPIP Core. La taille maximale du logo du site en pixels, on permet (...)

  • Mediabox : ouvrir les images dans l’espace maximal pour l’utilisateur

    8 février 2011, par

    La visualisation des images est restreinte par la largeur accordée par le design du site (dépendant du thème utilisé). Elles sont donc visibles sous un format réduit. Afin de profiter de l’ensemble de la place disponible sur l’écran de l’utilisateur, il est possible d’ajouter une fonctionnalité d’affichage de l’image dans une boite multimedia apparaissant au dessus du reste du contenu.
    Pour ce faire il est nécessaire d’installer le plugin "Mediabox".
    Configuration de la boite multimédia
    Dès (...)

Sur d’autres sites (7195)

  • FFmpeg Centos Compile Error - caused by libwebp (error : implicit declaration of function ‘libwebp_error_to_averror’)

    2 septembre 2022, par fvid1

    I'm trying to compile FFmpeg on Centos 7.9. I followed the official instructions : https://trac.ffmpeg.org/wiki/CompilationGuide/Centos

    


    I need support for WebP images, so I installed libwebp and libwebp-devel via YUM, and used the option --enable-libwebp.

    


    But at the ffmepg "make" stage, the following error is returned :

    


    CC      libavcodec/libwebpenc_common.o
libavcodec/libwebpenc_common.c: In function ‘ff_libwebp_get_frame’:
libavcodec/libwebpenc_common.c:283:17: error: implicit declaration of function ‘libwebp_error_to_averror’ [-Werror=implicit-function-declaration]
                 ret = libwebp_error_to_averror(pic->error_code);
                 ^
cc1: some warnings being treated as errors
make: *** [libavcodec/libwebpenc_common.o] Error 1


    


    Does anyone know why this error is occuring and how it can be corrected ?

    


    I've tried compiling without using --enable-libwebp and it works fine.

    


  • Continuous RTMP Streaming with FFmpeg Without Restarting the Process for New Videos

    3 avril 2024, par 刘小佳

    I'm facing a challenge with my workflow and would appreciate any guidance or solutions you might have. My business scenario involves a service that periodically generates new video files locally (e.g., 1.mp4, 2.mp4, ...). These files are then streamed to an RTMP server using FFmpeg, and clients pull the stream via HTTP-FLV for playback.

    


    My goal is to ensure continuous streaming between video files without restarting the FFmpeg process each time a new video is ready to be streamed. Restarting FFmpeg for each new file introduces a disconnect in the client playback, which I'm trying to avoid to maintain stream continuity.

    


    I've explored several approaches based on the FFmpeg Concatenate wiki (https://trac.ffmpeg.org/wiki/Concatenate), but haven't achieved the desired outcome :
    
Approach 1 :
    
Using a list.txt file with ffconcat version 1.0 and dynamically updating the file (next.mp4) being played :

    


    ffconcat version 1.0
file next.mp4
file next.mp4


    


    And then streaming with :
ffmpeg -re -stream_loop -1 -f concat -i list.txt -flush_packets 0 -f flv rtmp://xxx
    
However, when attempting to replace next.mp4 (e.g., moving 2.mp4 to next.mp4 during the streaming of 1.mp4), I encountered a "device busy" error.
    
Approach 2 :
    
Using a nested list approach where list1.txt includes 1.mp4 and list2.txt, and vice versa :

    


    // list1.txt
ffconcat version 1.0
file '1.mp4'
file 'list2.txt'
// list2.txt
ffconcat version 1.0
file '2.mp4'
file 'list1.txt'


    


    Streaming with : ffmpeg -re -stream_loop -1 -f concat -i list1.txt -flush_packets 0 -f flv rtmp://xxx
    
In this setup, I tried modifying list1.txt to replace 1.mp4 with 3.mp4 during the streaming of 2.mp4, but FFmpeg would loop back to 1.mp4 and 2.mp4 before streaming 3.mp4 in the next cycle.

    


    Am I missing something in my methods ? Does anyone have a better approach to fulfill this requirement ? Any help would be greatly appreciated !

    


  • Adding HEVC reference decoder to ffmpeg framework

    4 mars 2014, par Zax

    I have a tweaked HM reference code of HEVC Decoder based on my requirements. I also know that FFMPEG version 2.1 onwards supports HEVC. But its a necessity for me to integrate my modified HM code.

    Hence I have gone through the post :

    http://wiki.multimedia.cx/index.php?title=FFmpeg_codec_howto

    According to this post, I need to define some functions that are needed to add a new decoder support to FFMPEG framework.

    The structure is : typedef struct AVCodec

    I have defined a structure as shown below :

    AVCodec HMHEVC_decoder =
    {
       .name           = "hmhevc",
       .type           = AVMEDIA_TYPE_VIDEO,
       .id             = AV_CODEC_ID_HMHEVC,

       .init           = hmhevc_decode_init,
       .close          = hmhevc_decode_close,
       .decode         = hmhevc_decode_frame,
    };

    However, looking at the other examples, I feel I have to add another variable like :

       .priv_data_size = sizeof(HEVCContext),

    But the problem is that I don't have any such context. So in case I don't define this, what are the things that FFMPEG framework wont provide my decoder ?

    Also is definition of this private data context compulsary ?

    What are the other fields that have to be compulsorily defined ?

    My main intention is that FFPLAY should be able to play the decoded frame.