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  • Soumettre améliorations et plugins supplémentaires

    10 avril 2011

    Si vous avez développé une nouvelle extension permettant d’ajouter une ou plusieurs fonctionnalités utiles à MediaSPIP, faites le nous savoir et son intégration dans la distribution officielle sera envisagée.
    Vous pouvez utiliser la liste de discussion de développement afin de le faire savoir ou demander de l’aide quant à la réalisation de ce plugin. MediaSPIP étant basé sur SPIP, il est également possible d’utiliser le liste de discussion SPIP-zone de SPIP pour (...)

  • Ajouter notes et légendes aux images

    7 février 2011, par

    Pour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
    Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
    Modification lors de l’ajout d’un média
    Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...)

  • Submit bugs and patches

    13 avril 2011

    Unfortunately a software is never perfect.
    If you think you have found a bug, report it using our ticket system. Please to help us to fix it by providing the following information : the browser you are using, including the exact version as precise an explanation as possible of the problem if possible, the steps taken resulting in the problem a link to the site / page in question
    If you think you have solved the bug, fill in a ticket and attach to it a corrective patch.
    You may also (...)

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  • Encode Frames to Video with C Library

    31 juillet 2018, par NetherGranite

    For the sake of continuity, let us assume "RGB values" are the following :

    typedef struct RGB {
       uint8_t r, g, b;
    } rgb;

    However, if you feel that a different color space is more appropriate for this question, please use that instead.

    How might I go about writing 2D arrays of RGB values to a video in C given an output format and framerate ?

    Before I continue, I should specify that I wish to be able to do this all within one program. I am trying to add functionality to an application that would allow it to compile videos frame by frame without having to leave it.

    Additionally, my needs for this functionality are extremely basic ; I simply need to be able to set individual pixels to certain colors.

    The closest I have come to a solution so far is the C library FFmpeg. Allow me to describe what I was able to learn on my own :

    After looking through its documentation, I came across the function avcodec_send_frame(avctx, frame), whose parameters are of the types AVCodexContext* and const AVFrame* respectively. If these are not the right tools for what I am trying to do, please ignore the rest of the question and instead point me towards what I should be using.

    However, I do not know which fields of avctx and frame must be set manually and which do not. The reason I assume some do not is because both are extremely large structures, but correct me if I am wrong.

    Question 1 : What values of an AVCodecContext and AVFrame must be set ? Of these, what is/are the recommended value(s) for each of them ?

    Additionally, I was only able to find instructions on how to initialize an AVFrame (using av_frame_alloc() and av_frame_get_buffer()) but not for an AVCodexConstant.

    Question 2 : Is there a proper way to initialize an AVCodexConstant ? And just in case, is the method of initializing an AVFrame described above correct ? Do any of the fields of either have a proper method of initialization ?

    Also, I was not able to find official documentation on how to take this AVCodexConstant (which I assume contains the video information) and turn it into a video. I apologize if the documentation for this is easy to find and I just missed it.

    Question 3 : How do I turn an AVCodexConstant into a file of a given format ?

    And, given my limited knowledge :

    Question 4 : Are there any other parts to this process that I am missing, and do I have any of the above parts wrong ?


    Please keep in mind that I found out about FFmpeg for the first time very recently, and as a result, I am a complete beginner to this. Additionally, my experience with C is very limited, so I would greatly appreciate it if you could note which files need to be included with #include.

    Feel free to even go as far as recommending something other than FFmpeg, just as long as it is written in C. I do not need power-user options, but I would greatly prefer flexibility in what audio and video file types the library can handle.


    Addressing Potential Duplicates

    I appologize for how long this section is ; I just want to have my bases covered. I heavily apologize, however, if this is in fact a duplicate of a question that I was just unable to find.

    • ffmpeg C API documentation/tutorial [closed] — This question was too open-ended and received answers pointing the asker towards a tutorial at dranger.com, a tutorial that confusingly muddied the waters by focusing heavily on a graphics library of choice. Please do not take this as me saying it is bad ; I am just enough of a beginner that I could not wade through it all.
    • Encoding frames to video with ffmpeg — Although this question seems to have been asking the same thing, it is geared towards Unreal Engine 4, and the asker provided sample code, making it difficult for me to understand which of parts of the accepted answer were necessary for me and which were not.
    • How to write frames to a video file ? — While this also asked the same thing, the accepted answer simply provides a command instead of an explanation of code.
    • YUV Raw frames to video stream — While the accepted answer for this question is a command, the question states that it is looking for a way to encode frames generated by C++ code. Is there some way to run commands in code that I haven’t been able to find ?
    • Converting sequenced frames to video — Not only is the asker’s code written in Python, but it also seems to use already-existing image files as frames.
    • How to write bitmaps as frames to H.264 with x264 in C\C++ ? — The accepted answer seems to describe a process that would take multiple applications, but I could be wrong as I am enough of a beginner that I am not sure exactly what it means other than Step 3.
    • How to write bitmaps as frames to Ogg Theora in C\C++ ? — Although it isn’t a problem that the question specifies the ogg format, it is a problem that the accepted answer suggests libtheora, which appears to only work with ogg files.
  • Revision 36104 : Une petite erreur sur un message de la mutu grossissant pour pas grand ...

    11 mars 2010, par kent1@… — Log

    Une petite erreur sur un message de la mutu grossissant pour pas grand chose le texte

  • Revision 34497 : Premier jet de la categorie maintenance

    16 janvier 2010, par eric@… — Log

    Premier jet de la categorie maintenance