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  • Menus personnalisés

    14 novembre 2010, par

    MediaSPIP utilise le plugin Menus pour gérer plusieurs menus configurables pour la navigation.
    Cela permet de laisser aux administrateurs de canaux la possibilité de configurer finement ces menus.
    Menus créés à l’initialisation du site
    Par défaut trois menus sont créés automatiquement à l’initialisation du site : Le menu principal ; Identifiant : barrenav ; Ce menu s’insère en général en haut de la page après le bloc d’entête, son identifiant le rend compatible avec les squelettes basés sur Zpip ; (...)

  • Mise à disposition des fichiers

    14 avril 2011, par

    Par défaut, lors de son initialisation, MediaSPIP ne permet pas aux visiteurs de télécharger les fichiers qu’ils soient originaux ou le résultat de leur transformation ou encodage. Il permet uniquement de les visualiser.
    Cependant, il est possible et facile d’autoriser les visiteurs à avoir accès à ces documents et ce sous différentes formes.
    Tout cela se passe dans la page de configuration du squelette. Il vous faut aller dans l’espace d’administration du canal, et choisir dans la navigation (...)

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  • Real time stereo video stream. How to start

    29 juin 2015, par victor jung

    Here is my problem :

    I have at one side two webcams plugged in a linux computer, and on the other side, an android smartphone. My goal is to program a real time stream of the 2 webcams, and display that stream on the smartphone (to be used in a google cardboard mask). I read quite a lot on the subject, and I found several way to achieve this.

    First there is ffmpeg, which could encode and stream.

    But I need to modify the pictures at some point, to re-size them / or to ad some kind of distortion. So I thought it would be great if I can get the 2 images, with openCv maybe, playwith them, build a new one, and stream them, but how could ffmpeg deal with the newly created image ?

    The other option would be to get the 2 pics and play with them with openCv too, but then, hardcode a stream over, UDP in RTP style, but wouldnt be hard to display the stream nicely on the phone ?, and how to cut the image to fit in small packets ?

    Thanks for your help, I am still digging in the subject, so if you have any other way to do it I am taking !

    ps : My introducing Hello, won’t stay at the beginning of my message...
    Have a nice day every body.
    d-4 before frieday.

  • avdevice/decklink_enc : Add support for compressed AC-3 output over SDI

    7 avril 2023, par Devin Heitmueller
    avdevice/decklink_enc : Add support for compressed AC-3 output over SDI

    Extend the decklink output to include support for compressed AC-3,
    
encapsulated using the SMPTE ST 377:2015 standard.
    

    This functionality can be exercised by using the "copy" codec when
    
the input audio stream is AC-3.  For example :
    

    ./ffmpeg -i /foo.ts -codec:a copy -f decklink 'UltraStudio Mini Monitor'
    

    Note that the default behavior continues to be to do PCM output,
    
which means without specifying the copy codec a stream containing
    
AC-3 will be decoded and downmixed to stereo audio before output.
    

    Thanks to Marton Balint for providing feedback.
    

    Signed-off-by : Devin Heitmueller <dheitmueller@ltnglobal.com>
    
Signed-off-by : Marton Balint <cus@passwd.hu>
    • [DH] libavdevice/decklink_enc.cpp

  • Can't maintain desired fps with ffmpeg live stream when overlay is added

    1er avril 2019, par jawsware

    I’m attempting to produce a 4K live stream for YouTube.

    I’m capturing 2160p30 frames from a BlackMagic Design DeckLink Mini Recorder. I’m passing those frames to ffmpeg in their raw 8-bit 4:2:2 format. I’m able to achieve 30 fps encoding ( 16kbits/s and q= in the high 20s to low 30s) with my current parameters which are :

    ffmpeg -threads:v 2 -threads:a 8 -filter_threads 2
    
-f rawvideo -framerate 30 -pixel_format uyvy422 -video_size 3840x2160 -i \\.\pipe\videopipe
    
-f s16le -ac 2 -ar 44100 -i \\.\pipe\audiopipe
    
-r 30 -g 60 -c:v h264_nvenc -pix_fmt yuv420p -preset fast -profile main
    
-b:v 16000K -maxrate 24000k -bufsize 6000k
    
-f flv "rtmp://a.rtmp.youtube.com/live2/xxxx-xxxx-xxxx-xxxx"

    I’m dilemma is that once I introduce an overlay graphic, my encoding fps drops to 28 at best. Which leads me to believe I’m barley achieving the 30 fps without the overlay. I’m only adding these parameters to include the overlay :

    -i logo.png
    

    
-filter_complex "overlay=100:100"

    I further diminish the encoding fps (20 fps max) when I introduce a dynamic overlay which I feed to ffmpeg through an additional pipe.

    My questions are 1.) is there a better set a parameters I could be using to encode the 4K stream ? 2.) is there a better way to include the overlay ?

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