Draws a grid of conigurable size

draw_grid.py

#!/usr/bin/python

from PIL import Image


def draw_grid(size_x=1920, size_y=1080, grid_x=3, grid_y=3, border=2, img_x=0, img_y=0):
    if img_x == 0 or img_y == 0:
        img_x, img_y = size_x, size_y
    img = Image.new('RGB', (img_x, img_y), 'white')
    pixels = img.load()
    tile_x = size_x / grid_x
    tile_y = size_y / grid_y
    
    for x in range(img.size[0]):
        for y in range(img.size[1]):
            if (x % tile_x <= border or tile_x - x % tile_x <= border or
                    y % tile_y <= border or tile_y - y % tile_y <= border):
                pixels[x, y] = (0, 0, 0)
            if x >= size_x or y >= size_y:
                pixels[x, y] = (127, 127, 127)
    img.show()


draw_grid(3840, 2112, 3, 3, 1, 3840, 2160)