crea sprite en base a muchas imgs, sacado de debumode on

sprite.py

from PIL import Image

path = '/Users/gimenete/Desktop/famfamfam_silk_icons_v013/icons/'
names = ['add.png', 'accept.png', 'anchor.png', 'bomb.png', 'cd_add.png', 'clock.png']
output = 'sprites.png'
vpadding = 16
padding = 2

w = 0
h = 0
images = {}

for name in names:
    im = Image.open(path+name)
    images[name.split('.')[0]] = im
    width, height = im.size
    if width > w:
        w = width
    h += height
    h += vpadding

canvas = Image.new('RGBA', (w, h))
h = 0
i = 0
for name in images:
    im = images[name]
    width, height = im.size
    canvas.paste(im, (0, h))
    print '.s_%s { background:url(%s) 0px -%dpx no-repeat; padding-left: %dpx;}' % (name, output, h, (width+padding))
    h += height
    h += vpadding

canvas.save(output, 'PNG')