How to best install v4l2loopback on Linux Mint?

Question

I am trying to create a virtual webcam from OBS(26.1.1) so I can feed it to Zoom. I am Linux Mint 20.1 Cinnamon, version 4.8.6, Kernel 5.4.0-64-generic.

I did:

sudo apt-get install v4l2loopback-dkms
sudo apt-get install v4l2loopback-utils

but v4l2loopback is not showing up as an option in zoom

I went to the v4l2loopback github page, where it suggested I should build it from scratch and install it into my kernel. I tried to build from scratch and immediately ran into problems with the make command.

make -C /lib/modules/`uname -r`/build M=/home/berggren/Downloads/v4l2loopback-main modules
make[1]: Entering directory '/usr/src/linux-headers-5.4.0-64-generic'
  Building modules, stage 2.
  MODPOST 1 modules
make[1]: Leaving directory '/usr/src/linux-headers-5.4.0-64-generic'
make -C utils
make[1]: Entering directory '/home/berggren/Downloads/v4l2loopback-main/utils'
cc  -I..   v4l2loopback-ctl.c   -o v4l2loopback-ctl
v4l2loopback-ctl.c:1:10: fatal error: sys/types.h: No such file or directory
    1 | #include <sys/types.h>
      |          ^~~~~~~~~~~~~
compilation terminated.
make[1]: *** [<builtin>: v4l2loopback-ctl] Error 1
make[1]: Leaving directory '/home/berggren/Downloads/v4l2loopback-main/utils'
make: *** [Makefile:85: utils/v4l2loopback-ctl] Error 2

I didn't go further because I wasn't sure I was going in the right direction with that.

Could someone explain the correct procedure for installing v4l2loopback?

Answer 1

1. installing v4l2loopback-dkms will install the modules on your system (at least: if all goes well), but it will not load the modules for you
2. so you need to manually load the module with something like modprobe v4l2loopack
3. in order for zoom to use the device, you will first have to attach OBS-studio to it.

you probably need to pass the exlusive_caps=1 option when loading the module, in order for zoom to recognise it.