v4l2loopback error

[toto6976]

Hi,
here is the error message using v4l2loopback :

$ scrcpy --v4l2-sink=/dev/video1
scrcpy 1.21 <https://github.com/Genymobile/scrcpy>
INFO: Video orientation is locked for v4l2 sink. See --lock-video-orientation.
/usr/share/scrcpy/scrcpy-server: 1 fil...shed. 0.2 MB/s (39473 bytes in 0.166s)
[server] INFO: Device: LGE LG-H870 (Android 11)
INFO: Renderer: opengl
INFO: OpenGL version: 2.1 Mesa 23.2.1-1ubuntu3.1~22.04.2
WARN: Trilinear filtering disabled (OpenGL 3.0+ or ES 2.0+ required)
INFO: Initial texture: 1440x2880
ERROR: Failed to open output device: /dev/video1
ERROR: Could not open frame sink 1
ERROR: Could not open decoder sinks
ERROR: Could not open packet sink 0
ERROR: Could not open stream sinks
WARN: Device disconnected
WARN: Killing the server...

I posted the message in the wrong place. Can you move it to the correct section please?
https://github.com/umlaeute/v4l2loopback/issues

[rom1v]

scrcpy 1.21 https://github.com/Genymobile/scrcpy

First of all, that's a very old and obsolete version.

ERROR: Failed to open output device: /dev/video1

How did you create the v4l2loopback before calling scrcpy?

[toto6976]

I followed this link : https://github.com/Genymobile/scrcpy/blob/master/doc/v4l2.md

[rom1v]

v4l2-ctl --list-devices
ls /dev/video*

?

[toto6976]

v4l2-ctl --list-devices
I connect the phone with ssh tunnel : so Acer is the server, not the phone

$ v4l2-ctl --list-devices
Acer Crystal Eye webcam: Acer C (usb-0000:00:1a.7-6):
	/dev/video0
	/dev/video1
	/dev/media0

$ ls /dev/video*
/dev/video0  /dev/video1

[rom1v]

I connect the phone with ssh tunnel

First, does it work without an ssh tunnel? (this might add permissions issues)
You use an SSH tunnel between what and what here?

[toto6976]

You use an SSH tunnel between what and what here?

#5254

Your server: 65.xx.xxx.yyy (machine with local ip: 192.168.1.72).
Your client: localhost (machine with the local ip: 192.168.0.251).

I assume both computers are on Linux.

From the client, execute:

ssh -CN -L5038:localhost:5037 -R27183:localhost:27183 65.xx.xxx.yyy
# keep this open

[toto6976]

First, does it work without an ssh tunnel?

I will try this afternoon

[rom1v]

So your v4l2loopback module must be on the local client (not the server).

Scrcpy uses the tunnel to communicate to the adb daemon running on the remote computer (where the phone is connected), and displays (either in a window or to a v4l2 sink) the content locally.

[toto6976]

So, i am at home : on my pc, i follow this : https://github.com/Genymobile/scrcpy/blob/master/doc/v4l2.md

error with : sudo modprobe v4l2loopback

$ sudo modprobe v4l2loopback
modprobe: FATAL: Module v4l2loopback not found in directory /lib/modules/6.0.0-kali6-amd64

[rom1v]

So you must install it (as explained at the top of the page you linked).

[toto6976]

it is installed. But I still get the modprobe error...

sudo apt install v4l2loopback-dkms                    
v4l2loopback-dkms est déjà la version la plus récente (0.13.2-1).
Summary:
  Upgrading: 0, Installing: 0, Removing: 0, Not Upgrading: 761