how to add border around an image in opencv python

Question

If I have an image like below, how can I add border all around the image such that the overall height and width of the final image increases but the height and width of the

Answer 1

Add border using openCV

import cv2
white = [255,255,255]
img1 = cv2.imread('input.png')
constant= cv2.copyMakeBorder(img1,20,20,20,20,cv2.BORDER_CONSTANT,value=white)
cv2.imwrite('output.png',constant)