Create openCV VideoCapture from interface name instead of camera numbers

Question

The normal way to create a videocapture is this:

cam = cv2.VideoCapture(n)

where n corresponds to the number of /dev/video0,

Answer 1

Instead of the suggested solution I found a shorter one, that feels a little bit hacky.

I just look at where the symbolic link points, find the integer in it, and then use that.

import subprocess

cmd = "readlink -f /dev/CAMC"
process = subprocess.Popen(cmd.split(), stdout=subprocess.PIPE)

# output of form /dev/videoX
out = process.communicate()[0]

# parse for ints
nums = [int(x) for x in out if x.isdigit()]

cap = cv2.VideoCapture(nums[0])