Overlay numbers from 0000 to 9999 on a picture
from PIL import Image, ImageFont, ImageDraw

BACKGROUND = '/path/to/background.png'
OUTPUT = '/path/to/mypicture_{0:04d}.png'
START = 0
STOP = 9999

# Create a font object from a True-Type font file and specify the font size.
fontobj = ImageFont.truetype('/path/to/font/arial.ttf', 24)

for i in range(START, STOP + 1):
    img = Image.open(BACKGROUND)
    draw = ImageDraw.Draw(img)
    # Write a text over the background image.
    # Parameters: location(x, y), text, textcolor(R, G, B), fontobject
    draw.text((0, 0), '{0:04d}'.format(i), (255, 0, 0), font=fontobj)
    img.save(OUTPUT.format(i))

print 'Script done!'