How can I use USB camera??

[peng4975]

This code is excellent.
It is very helpful to me who is studying raspberry pi.

How can I use a USB camera instead of a pi cam?
I think it should not just change 'dev' because current code using PI cam lib.
Therefore, I need your opinion as an expert.

[mnishig]

You can not use USB camera with this app.
Because this app depends on picamera python module . picamera module supports Pi Camera Hw only.

USB camera maybe implemented V4lL interface, but in most cases document is not opened by camera vender.