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  • Demande de création d’un canal

    12 mars 2010, par

    En fonction de la configuration de la plateforme, l’utilisateur peu avoir à sa disposition deux méthodes différentes de demande de création de canal. La première est au moment de son inscription, la seconde, après son inscription en remplissant un formulaire de demande.
    Les deux manières demandent les mêmes choses fonctionnent à peu près de la même manière, le futur utilisateur doit remplir une série de champ de formulaire permettant tout d’abord aux administrateurs d’avoir des informations quant à (...)

  • Contribute to documentation

    13 avril 2011

    Documentation is vital to the development of improved technical capabilities.
    MediaSPIP welcomes documentation by users as well as developers - including : critique of existing features and functions articles contributed by developers, administrators, content producers and editors screenshots to illustrate the above translations of existing documentation into other languages
    To contribute, register to the project users’ mailing (...)

  • 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 (...)

Sur d’autres sites (5703)

  • FFMPEG Audio, video out of sync

    5 mars 2012, par geeknizer

    I'm creating Video using FFMPEG from pngs. The problem is on creating the video, and combining with video, its never in sync.

    Create video :

    ffmpeg -i /home/ubuntu/pngs/* -vcodec libvpx -r 25 -b 1024k -y video.avi

    generate audio

    ffmpeg -y -f s16le -ar 44100 -ac 2 -i wav_file.wav -acodec libvorbis video.avi

    these snapshots were taken at 25fps from a video. Audio is also extracted from same source.

  • How to quantify and compare video quality

    24 mars 2015, par user940154

    I have a set of uncompressed videos in YUV format.

    I have obtained several derived copies in various formats and resolutions from these yuv files using FFmpeg transcoding. (YUVs ----> X Derived Copies)

    What I have also done is, transcode the yuv’s into same resolution AVIs, and now obtained the same set of derived (transcoded) videos treating the AVIs as master. (AVIs ----> X Derived Copies)

    Now I wish to compare the quality of transcoded videos, when derived from AVIs to those derived from YUVs.

    Is there any way for me to do this using FFmpeg. How ? If not, can you please suggest some good open source software to do this.

    Thanks

  • How to optimize video to animated GIF conversion using PHP + shell commands

    15 mars 2012, par user1070798

    I have a web application that converts any video into an animated GIF. The app runs in PHP and the following steps are executed through php's shell_exec :

    1. Scale video to smaller dimensions, if they are large (ffmpeg -i $in -s 200x150 -an $out)
    2. Use ffmpeg to extract 1 jpeg every x seconds (ffmpeg -i $in -ss $ss -vframes 1 $out)

    3. Convert jpegs to animated GIF using imagick (convert -delay $delay -loop 0 $dir/* $out)

      aside - the reason I don't use the ffmpeg gif89a output is because the quality sucks.

    I want to be able to except any major image format, but the most common will probably be .flv (flash) and .avi/.mpg.

    My application runs fine, but I am a perfectionist and it needs to be faster for scalability.

    My web server has 16 cores and I would like to utilize them as much as possible, but .flv multi-threading appears to not be supported by ffmpeg, while .avi and some others are supported. Also, ffmpeg doesn't support multi-threading when outputting to jpegs.

    Does anyone know of any other programs that support multi-threading for .flv and others ? Are there any more efficient methods to create an animated GIF from video, while maintaining relatively decent quality (aka not the 100-color palette that ffmpeg supports) ?

    Also, if anyone knows which codecs might perform best for stages 1 and 2, particularly with flv, I'd love to know. I've done hours of testing, but there are just so many options I haven't come to any solid conclusions.

    ***Update : My online app is working well so far animated gif generator. I would still love to make it faster though, so if anyone has run into similar circumstances... let me know !

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