If you are on Arch Linux and experiencing issues with your OBS Virtual Camera not working anymore after upgrading your kernel, here might be the solution for you:
#v4l2loopback
Dos horas invertidas en "arreglar" #v4l2loopback porque no conseguía hacer funcionar la cámara virtual de OBS en el navegador...
¡Y no era problema de v4l2-loopback!
:bc_glare:
Bueno sí, un poco, pero la solución no funcionaba porque únicamente estaba haciendo pruebas en #Jitsi... Y resulta que Jitsi es demasiado quisquilloso con los parámetros de cámara para detectarlas (por ejemplo, no las reconoce si se configuran a más de 30 FPS o con un formato de video distinto a YUYV 4:2:2). Otras aplicaciones web de videollamada funcionaban sin necesidad de verificar esos parámetros.
En fin, todo sea por la ciencia...
@eri yes, you can even do the opposite in #Linux with #V4L2loopback "devices" and basically shove your composed videostream into a device file and use that as a #webcam in your application...
If anyone, using Fedora Linux 42, has issues with OBS-Studio and the Virtual-Camera mode:
That's because of an incompatibility between OBS-Studio 31.0 and the v4l2loopback Kernel module in version 0.14.0.
The fix for that is in obs 31.0.3, which is on the way from testing to stable right now. Should be offered as an RPM update within the next days.
Fedora Bugfix Update:
https://bodhi.fedoraproject.org/updates/FEDORA-2025-85fcdbf461
Upstream Bug: https://github.com/obsproject/obs-studio/issues/11891
Writing down this for myself for the most part to get idea what to write to the cover letter later on.
My RFC driver model for v4l2-loopback will be centered around /dev/video_loop. It has only single ioctl (OOT driver has three), which has N input parameters (describing metadata for the video device) and exactly two output parameters:
1. capture_fd: communications end point for the virtual capture device. Created using anonymous inode.
2. output_nr: /dev/video{output_nr} is the V4L2 device for the output.
There is no query ioctl because any sane program should at minimum know what resources it creates and should not have privilege in the first place to peak others resources.
There is no remove ioctl because close(capture_fd) destroys /dev/video{output_nr}
Neither overlay nor dma-buf support in the initial version (should be reviewed from basis that these can be extended later on).
#linux #kernel #video4linux #v4l2loopback
My RFC driver model for v4l2-loopback will be centered around /dev/video_loop. It has only single ioctl (OOT driver has three), which has N input parameters (describing metadata for the video device) and exactly two output parameters:
1. capture_fd: communications end point for the virtual capture device. Created using anonymous inode.
2. output_nr: /dev/video{output_nr} is the V4L2 device for the output.
There is no query ioctl because any sane program should at minimum know what resources it creates and should not have privilege in the first place to peak others resources.
There is no remove ioctl because close(capture_fd) destroys /dev/video{output_nr}
Neither overlay nor dma-buf support in the initial version (should be reviewed from basis that these can be extended later on).
#linux #kernel #video4linux #v4l2loopback
@marquito nach einfach ne #Videoschleife mittels OBS Studio & #V4L2loopback oder nen #CamLink als #Webcam & Zweitrechner als Videoquelle...
I didn't remember that for #obs to show the *start virtual camera* button, you had to install and load #v4l2loopback first.
@olmitch jist don't turn on the camera at all or use #V4L2loopback to play a "conference nodding video" instead.
@redcat @schenklklopfer +9001%
Protip: "Office Nodding" als Schleife per #V4L2loopback für den Kamera-Feed einblenden für all die #Webcam-Fetischist*innen...
Thanks to #v4l2loopback, #ffmpeg, and https://github.com/nhtua/greencam, I have finally managed to cobble together a GPU-powered virtual green screen effect in #OBS Studio for #Linux that doesn't sacrifice the ability to display the unaltered camera stream. 🤘
Nice. #trickfilm mit Spiegelrelex bauen.
#v4l2loopback
#gphoto2
#heronanimation
¡¡Que hermosura!! solo en gnu/linux
ffmpeg -re -i video -f v4l2 -pix_fmt yuv420p /dev/video0
Costo, pero lo logré ya transmito en multiplataformas, solo me falta un #icecast y ya sería completo
con un consumo mínimo comparado a #OBS
#ffmpeg #v4l2loopback #snd-aloop
Como montar una webcam "falsa" con un video
Esto sirve para transmitir videos por ejemplo en #jitsi sin necesidad de usar una nube propietaria
ffmpeg -re -i video.webm -vf format=yuv420p -f v4l2 $(v4l2-ctl --list-device | grep -E1 Dummy | tail -n1)
@petrichor check out this https://github.com/floe/backscrub
i did not test it, but they solved it like i would do. Its quite easy to create video loopbacks in linux, which means that basically any video effect is possible. It seems to be work in progress though.
#v4l2loopback
I decided I want to do some basic manipulations of the camera output. After some searches I came across #v4l2loopback which is a kernel module that creates a virtual video device:
https://github.com/umlaeute/v4l2loopback
Built and loaded it and now I have /dev/video2 as well and I can send my video into it.
A useful command is vlc v4l2:///dev/video2
Next: some #gstreamer pipes that send video into it. Otherwise that above command shows nothing.
>>>
I just discovered I can use a #DSLR as a webcam using #v4l2loopback 🙂 no more low image quality video calls!
Wir haben heute eine neue Folge Sibyllinissche Neuigkeiten aufgezeichnet. SN34 berichtet unter anderem über Konferenzsetups mit @bigbluebutton@twitter.com, @OBSProject@twitter.com und #v4l2loopback Geräten. Außerdem gibt es Infos @The_Pi_Hole@twitter.com v5 und Anekdoten von der Kommandozeile Thema . #c3e #podcast
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