This Linux module implements a simplified virtual V4L2 compatible camera device driver with raw framebuffer input.

After running make, you should be able to generate the following files:

• vcam.ko - Linux kernel module;
• vcam-util - Sample tility to configure virtual camera device(s);

Before loading this kernel module, you have to satisfy its dependency:

$ sudo modprobe videobuf2_vmalloc videobuf2_v4l2

The module can be loaded to Linux kernel by runnning the command:

$ sudo insmod vcam.ko

Expectedly, two device nodes will be created in /dev:

• videoX - V4L2 device;
• vcamctl - Control device for virtual camera(s), used by control utility vcam-util;

In /proc directory, device file fbX will be created.

The device if initialy configured to process 640x480 RGB24 image format. By writing 640x480 RGB24 raw frame data to /proc/fbX file the resulting video stream will appear on corresponding /dev/videoX V4L2 device(s).

Run vcam-util --help for more information about how to configure, add or remove virtual camera devices. e.g. list all available virtual camera device(s):

$ sudo ./vcam-util -l

You should get:

Available virtual V4L2 compatible devices:
1. vcamfb0(640,480,rgb24) -> /dev/video0

Install v4l-utils for retrieving more information:

$ sudo apt install v4l-utils

You can use this command to check if the driver is ok:

$ sudo v4l2-compliance -d /dev/videoX -f

It will return a bunch of test lines, with 1 failed and 0 warnings at the end.

You can check if all configured formats and emulated controls are ok with this command:

$ sudo v4l2-ctl -d /dev/videoX --all

You will get information as following:

Driver Info:
	Driver name   : vcam
	Card type     : vcam
	Bus info      : platform: virtual
	Driver version: 4.15.18
	Capabilities  : 0x85200001
		Video Capture
		Read/Write
		Streaming
		Extended Pix Format
		Device Capabilities

• akvcam
• v4l2loopback
• vivid: The Virtual Video Test Driver

vcam is released under the MIT License. Use of this source code is governed by a MIT License that can be found in the LICENSE file.