First you’ll need to install Ffmpeg and v4l2loopback and v4l-utils.
For Ffmpeg is easy as it comes bundled with most distros and so does v4l2-ctl.
sudo apt-get install ffmpeg v4l-utils
For v4l2loopback you need to first clone from their repository and do make install as follows
git clone https://github.com/umlaeute/v4l2loopback.git
cd v4l2loopback
sudo make && make install
once installed we need to copy the module to our modules folder
sudo cp v4l2loopback.ko /lib/modules/`uname -r `
sudo depmod -a
sudo modprobe v4l2loopback
once the module is loaded we can check that our dummy camera is installed and find out it’s name
v4l2-ctl --list-device
in my pc the output is as follows
Dummy video device (0x0000) (platform:v4l2loopback-000):
/dev/video1
Laptop_Integrated_Webcam_1.3M: (usb-0000:00:1a.0-1.5):
/dev/video0
As you can see the dummy camera has been installed and it is on dev/video1. Finally can well tell ffmpeg to grab an image and stream it to our virtual webcam.
ffmpeg -loop 1 -re -i testsrc.png -f v4l2 -vcodec rawvideo -pix_fmt yuv420p /dev/video1
Note that we used video1 for our dummy camera but yours may differ. Testsrc is the file that you will stream. For video you can also do
ffmpeg -re -i testsrc.avi -f v4l2 /dev/video1
Now you should be able to see your image shown in any app that uses webcam, for example you can test it with this handy online tool
I want to clarify that this method does not work on chromium, I tested it on Firefox.
This gist was created following this nice tutorial from linuxgamecast for desktop capturing
And v4l2loopbacks’s wiki
For more information check their wiki.