Generates an image with an EAN-8 barcode

gen_ean8.py

#!/usr/bin/env python
from PIL import Image
import sys

l_code = {
	0: '0001101',
	1: '0011001',
	2: '0010011',
	3: '0111101',
	4: '0100011',
	5: '0110001',
	6: '0101111',
	7: '0111011',
	8: '0110111',
	9: '0001011',
}

r_code = {
	0: '1110010',
	1: '1100110',
	2: '1101100',
	3: '1000010',
	4: '1011100',
	5: '1001110',
	6: '1010000',
	7: '1000100',
	8: '1001000',
	9: '1110100',
}

colors		= [(255, 255, 255), (0, 0, 0)]
height		= 150
sepheight	= 175
width		= 5
marginx		= 50
marginy		= 50

def draw_bars(pxl, bx, by, wd, hh, cols, stv):
	x = bx
	for e in stv:
		col = cols[1 if e == '1' else 0]
		for xx in range(x, x + wd):
			for y in range(by, by + hh):
				pxl[xx, y] = col
		x += wd
	return x - bx

if len(sys.argv) <= 2:
	print('Usage: %s <ean8> <output>' % sys.argv[0])
else:
	code = sys.argv[1]
	if len(code) != 8:
		print('Not an EAN-8')
		exit(1)
	img = Image.new('RGB', ((3+(7*4)+5+(7*4)+3) * width + (marginx*2), sepheight + (marginy*2)), colors[0])
	imgd = img.load()
	x = marginx

	x += draw_bars(imgd, x, marginy, width, sepheight, colors, '101') # First seperator
	f4code = ''.join(l_code[int(e)] for e in code[:4])
	x += draw_bars(imgd, x, marginy, width, height, colors, f4code) # First four numbers
	x += draw_bars(imgd, x, marginy, width, sepheight, colors, '01010') # Middle seperator
	l4code = ''.join(r_code[int(e)] for e in code[4:])
	x += draw_bars(imgd, x, marginy, width, height, colors, l4code) # Last four numbers
	x += draw_bars(imgd, x, marginy, width, sepheight, colors, '101') # Last seperator

	img.save(sys.argv[2])