import numpy as np
import cv2
import os

lit = 'RGB_image_path/rgb_image.png'
mask = 'mask_image_path/maks_image.png'

lit_image = cv2.imread(lit)
mask_image = cv2.imread(mask)

imgray=cv2.cvtColor(mask_image,cv2.COLOR_BGR2GRAY)
ret,thresh = cv2.threshold(imgray,127,255,1)
image, contours, hierarchy =  cv2.findContours(thresh,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)

if len(contours)>0:
    print('length is: ',len(contours))
    cnt = contours[0]
    x,y,w,h = cv2.boundingRect(cnt)

    draw_rec_lit_image=cv2.rectangle(lit_image,(x,y),(x+w,y+h),(0,0,255),2)


if cv2.waitKey() == ord('q'): #press q to close the output image window
        cv2.destroyAllWindows()