Combines an array of image files into a single bitmap with union (logical OR).

union_bitmaps.py

#!/usr/bin/env python3

# Combines an array of image files into one bitmap with union (logical OR).

# Requirements
# pip3 install opencv-python

import cv2
import numpy as np

infiles = [
    'colour-7.png',
    'colour-8.png',
    'colour-9.png'
    ]
outfile = 'colour-789.png'
o = None

for i in infiles:
    im = cv2.imread(i,cv2.IMREAD_GRAYSCALE) # load image
    p = np.array(im) >= 255 # binarize
    print(f'Opening file {i}:')
    print(p)
    if (o is None):
        o = p
    else:
        o = p + o  # Logical OR

# Save to outfile.
cv2.imwrite(outfile, o * 255)
print(f'Wrote file {outfile}.')