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  • Personnaliser les catégories

    21 juin 2013, par

    Formulaire de création d’une catégorie
    Pour ceux qui connaissent bien SPIP, une catégorie peut être assimilée à une rubrique.
    Dans le cas d’un document de type catégorie, les champs proposés par défaut sont : Texte
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    Administration > Configuration des masques de formulaire.
    Dans le cas d’un document de type média, les champs non affichés par défaut sont : Descriptif rapide
    Par ailleurs, c’est dans cette partie configuration qu’on peut indiquer le (...)

  • 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.
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  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 is the first MediaSPIP stable release.
    Its official release date is June 21, 2013 and is announced here.
    The zip file provided here only contains the sources of MediaSPIP in its standalone version.
    To get a working installation, you must manually install all-software dependencies on the server.
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  • ffmpeg audio - video sync issue (audio ahead of video) - while screen recording using x11grab

    12 juillet 2023, par maheshg

    While screen-recording using the below ffmpeg options I consistently get audio ahead of video, delay is in the order of few seconds

    


    ffmpeg cmd :

    


    ffmpeg -y -f x11grab -thread_queue_size 1024 -draw_mouse 0 -video_size 1920x1080 -i :0 -f pulse -thread_queue_size 1024 -i default -c:v libx264 -threads 0 -preset faster -c:a flac -async 1 -vsync 1 -crf 30 -crf_max 33 -f matroska output.mkv

    


    ffprobe output below :

    


    $ ffprobe demo.mkv 
ffprobe version 3.4.4-1~16.04.york0 Copyright (c) 2007-2018 the FFmpeg developers
  built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.10) 20160609
  configuration: --prefix=/usr --extra-version='1~16.04.york0' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  libavutil      55. 78.100 / 55. 78.100
  libavcodec     57.107.100 / 57.107.100
  libavformat    57. 83.100 / 57. 83.100
  libavdevice    57. 10.100 / 57. 10.100
  libavfilter     6.107.100 /  6.107.100
  libavresample   3.  7.  0 /  3.  7.  0
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Input #0, matroska,webm, from 'demo.mkv':
  Metadata:
    ENCODER         : Lavf57.71.100
  Duration: 01:00:31.93, start: 0.000000, bitrate: 416 kb/s
    Stream #0:0: Video: h264 (High), yuv420p(progressive), 1920x1080, 29.97 fps, 29.97 tbr, 1k tbn, 59.94 tbc (default)
    Metadata:
      ENCODER         : Lavc57.89.100 libx264
      DURATION        : 01:00:31.928000000
    Stream #0:1: Audio: flac, 48000 Hz, stereo, s16 (default)
    Metadata:
      ENCODER         : Lavc57.89.100 flac
      DURATION        : 01:00:30.912000000


    


    I have even tried using avoid_negative_ts flag, but it didnt help with the sync issue.

    


    


    OS : Ubuntu-18.04

    


    ffmpeg version : 3.4

    


    


    Update : (with ffmpeg-4.0)
I have since split this process into 2 parts and tried as shown below (quality is better, but audio/video sync is still an issue)

    


    # STEP-1: screen recording
/usr/bin/ffmpeg -y -f x11grab -thread_queue_size 1024 -draw_mouse 0 \
-video_size 1920x1080 -i :91141925 -f pulse -thread_queue_size 1024 \
-i virtual_sink.monitor -c:v libx264rgb -threads 0 -preset ultrafast \
-c:a flac -ac 1 -crf 0 -f matroska output.mkv

# STEP-2: audio/video encoding
/usr/bin/ffmpeg -y -i output.mkv -c:v libx264 -threads 0 \
-preset faster -pix_fmt yuv420p -c:a copy -ac 1 -crf 25 \
-f matroska final_output.mkv


    


    STEP-1 uses much less CPU during screen recording, but audio is still ahead of video. the display I am using is xvfb one in STEP-1 (since, this is a headless machine in the cloud)

    


    Also, i have tried flags -filter_complex aresample=44100 -vsync 1 in STEP-1 to no avail.

    


    Can someone please help !

    


    


    Update 2 : (with latest ffmpeg from git master)

    


    IT WORKED ! THANKS @llogan for the helpful comments.

    


    


  • FFMPEG UDP MPEG2TS to Cable TV Channel - Video & Audio Problems

    30 janvier 2019, par user2884023

    Channel Feed Distored Picture

    $ ffmpeg
    
-re
    
-i playlist1.txt
    
-b:v 15000k 
    
-bufsize 15000k
    
-maxrate 16000k
    
-f mpegts "udp://XXX.XXX.X.XXX:XXXX"

    I have mpeg2.ts files encoded to CBR15mbs.
    The files are set to different frame rates. Although initial testing was just playing 1 file.
    They are currently 1080p I think without declaring the frame rate, they are defaulting to 30fps.
    From the server locally via Port2 (that we are using to send our feed), everything plays fine via FFPLAY.
    The final out put local CATV is pixelated and distorted, the video is missing data playing slowly and the audio is choppy / distorted.
    I even tried just a 192kps .mp2 and it played distorted on the CATV channel.
    They set me up with a cable modem. 2 ports, 1 WAN, 1 a dedicated port to feed their head end and I have a fiber synchronous 20/20 connection.

    I am guessing its a packet issue, perhaps on our end with our FFMPEG setup ? And maybe FFPLAY isn’t as sensitive to the actual distro process.

    Perhaps the secret lies here, but there isn’t much info about them, even scouring the net.

    ?pkt_size=188&buffer_size=65535

    For example what is this one :

    broadcast=1|0

    Explicitly allow or disallow UDP broadcasting.

    I apologize if data is missing, please ask questions. I didn’t want to write a novel.

    I am hoping some can provide the correct code so my signal is corrected. I assume the problem is on our end, and not the CATV end. At least I can try some solutions on our end first. I can make real-time FFMPEG changes to the server, and see the channel results instantly so that helps.

    Finally, the fact it wouldn’t even play a .mp2 audio file cleanly on the channel, does make me wonder, is there a problem on their end, or is it a config on our end, and we just need the correct answer ?

  • ffmpeg screen recording using x11grab - audio video sync issue (audio ahead of video)

    19 décembre 2018, par maheshg

    While screen-recording using the below ffmpeg options I consistently get audio ahead of video, delay is in the order of few seconds

    ffmpeg cmd :

    ffmpeg -y -f x11grab -thread_queue_size 1024 -draw_mouse 0 -video_size 1920x1080 -i :0 -f pulse -thread_queue_size 1024 -i default -c:v libx264 -threads 0 -preset faster -c:a flac -async 1 -vsync 1 -crf 30 -crf_max 33 -f matroska output.mkv

    ffprobe output below :

    $ ffprobe demo.mkv 
    
ffprobe version 3.4.4-1~16.04.york0 Copyright (c) 2007-2018 the FFmpeg developers
    
  built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.10) 20160609
    
  configuration: --prefix=/usr --extra-version='1~16.04.york0' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
    
  libavutil      55. 78.100 / 55. 78.100
    
  libavcodec     57.107.100 / 57.107.100
    
  libavformat    57. 83.100 / 57. 83.100
    
  libavdevice    57. 10.100 / 57. 10.100
    
  libavfilter     6.107.100 /  6.107.100
    
  libavresample   3.  7.  0 /  3.  7.  0
    
  libswscale      4.  8.100 /  4.  8.100
    
  libswresample   2.  9.100 /  2.  9.100
    
  libpostproc    54.  7.100 / 54.  7.100
    
Input #0, matroska,webm, from 'demo.mkv':
    
  Metadata:
    
    ENCODER         : Lavf57.71.100
    
  Duration: 01:00:31.93, start: 0.000000, bitrate: 416 kb/s
    
    Stream #0:0: Video: h264 (High), yuv420p(progressive), 1920x1080, 29.97 fps, 29.97 tbr, 1k tbn, 59.94 tbc (default)
    
    Metadata:
    
      ENCODER         : Lavc57.89.100 libx264
    
      DURATION        : 01:00:31.928000000
    
    Stream #0:1: Audio: flac, 48000 Hz, stereo, s16 (default)
    
    Metadata:
    
      ENCODER         : Lavc57.89.100 flac
    
      DURATION        : 01:00:30.912000000

    I have even tried using avoid_negative_ts flag, but it didnt help with the sync issue.

    OS : Ubuntu-18.04

    ffmpeg version : 3.4

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