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  • Gestion des droits de création et d’édition des objets

    8 février 2011, par

    Par défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;

  • Supporting all media types

    13 avril 2011, par

    Unlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)

  • Keeping control of your media in your hands

    13 avril 2011, par

    The vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
    While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
    MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
    MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)

Sur d’autres sites (7831)

  • ffmpeg AAC audio encoding with libfdk_aac : difference between -q:a and -vbr quality parameters ?

    16 juin 2020, par RocketNuts

    I want to encode an audio file to AAC, using libfdk_aac, and I'm wondering about the quality parameters. I want to use variable bitrate encoding, not constant bitrate.

    



    It seems I can specify the quality either with the -vbr N parameter (with N=1..5) like this :

    



    ffmpeg -i input.flac -acodec libfdk_aac -vbr 4 output.m4a


    



    Or using the -q:a N parameter (here N=0..9) like this :

    



    ffmpeg -i input.flac -acodec libfdk_aac -q:a 7 output.m4a


    



    How are these two related, is there a substantial difference ? Do specific -q:a values correspond to certain -vbr values, or is it a different encoding approach altogether ?

    


  • no difference between h264 and h264_cuvid

    10 juillet 2020, par Ruslan Ablyazov

    I use libav to decode an RTSP stream. I tried two code options : with auto codec selection and with hardcoded codec.

    


    pCodec = avcodec_find_decoder (pFormatCtx->streams[p_InputVideoStreamIndex]->codecpar->codec_id);&#xA;//pCodec = avcodec_find_decoder_by_name ("h264_cuvid");&#xA;&#xA;LOG (info) &lt;&lt; "Video codec name" &lt;&lt; pCodec->name &lt;&lt; ". Full name:" &lt;&lt; (pCodec->long_name? PCodec->long_name: "<null>");&#xA;</null>

    &#xA;

    The avcodec_find_decoder() function returns h264 codec. The problem is that the speed and load on the CPU when using h264 is no different from h264_cuvid. What could be the reason ? When I use h264_cuvid, the video card is loaded by 2-3% more.

    &#xA;

    Video stream : 1920x1080 25 FPS (main and high profile).&#xA;Video card : NVIDIA Corporation GP107 [GeForce GTX 1050 Ti] (rev a1).&#xA;Processor : Intel (R) Core (TM) i5-8400 CPU @ 2.80GHz.

    &#xA;

    Compilation config ffmpeg :

    &#xA;

    ffmpeg version 4.3 Copyright (c) 2000-2020 the FFmpeg developers&#xA;  built with gcc 8 (Debian 8.3.0-6)&#xA;  configuration: --enable-gpl --enable-ladspa --enable-libpulse --enable-libsoxr --enable-libspeex --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --enable -libass --enable-libfreetype --enable-libmp3lame --enable-nonfree --disable-ffplay --enable-libxvid --enable-cuda --enable-cuda-nvcc --enable-cuda-sdk --enable- cuvid --enable-nvenc --enable-nonfree --enable-libnpp --enable-shared --extra-cflags = -I/usr/local/cuda/include --extra-ldflags = -L/usr/local/cuda/lib64&#xA;

    &#xA;

  • ffmpeg save difference between 2 videos to file

    10 août 2020, par 0x-1

    I'm currently trying to learn everything related to videos and encountered a problem that I need help with.

    &#xA;

    The Question is : How can I save the difference between 2 videos to a seperate file with ffmpeg ?
    &#xA;For example here is the ffplay command I'm trying with :&#xA;(Source : https://superuser.com/questions/854543/how-to-compare-the-difference-between-2-videos-color-in-ffmpeg)

    &#xA;

    ffplay -f lavfi "movie=left.mp4,setpts=PTS-STARTPTS,split=3[a0][a1][a2];&#xA;            movie=right.mp4,setpts=PTS-STARTPTS,split[b0][b1];&#xA;            [a0][b0]blend=c0_mode=difference[y];&#xA;            [a1]lutyuv=y=val:u=128:v=128[uv];&#xA;            [y][uv]mergeplanes=0x001112:yuv420p,pad=2*iw:ih:0:0[down];&#xA;            [a2][b1]hstack[up];[up][down]vstack"&#xA;

    &#xA;

    In this case I would want to have the bottom left video saved to a new file.
    &#xA;Can someone help me get together the right ffmpeg filter and explain the proccessing of ffmpeg ?

    &#xA;

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