fetch_placeholdit_imgs.py

#!/usr/env python
"""
Fetches a set of placeholder images from placehold.it. Iterates over the background colors specified, and
uses the same text for each slide. Image filenames contain an index, the size, and the bg color.

Warning: quick/dirty script. Would be cooler if options could be entered on the command-line. Also would
probably be cooler to use the subprocess module, instead of os.system()
"""
import os

# User options:
SLIDE_SIZE = '1280x640'
SLIDE_TEXT = 'Slide (1280x640)'
# specify an array of hex codes, each one will correspond to a resulting image.
colors = ['FF5050', 'CC0099', '3399FF', '00FF99', 'CC6699']

# Customize this at your own risk:
FN_PATTERN = 'slide-%(index)s-%(size)s-%(color)s.png'

# You can change this if you wish, check out http://placehold.it for info on their URL structure
URL_PATTERN = 'http://placehold.it/%(size)s/%(color)s?text=%(text)s'

make_filename = lambda index, color: FN_PATTERN % dict(index=index, color=color, size=SLIDE_SIZE)
make_url = lambda color: URL_PATTERN % dict(size=SLIDE_SIZE, color=color, text=SLIDE_TEXT)

cmds = ['wget -O %s "%s"' % (make_filename(i, color), make_url(color)) for i, color in enumerate(colors)]

# print cmds # <--- debug statement

[os.system(c) for c in cmds]