# -*- Mode: Python -*-

# if you enjoy your stereo images cross-eyed (or wide-eyed, try the
# '-r' option) rather than through silly colored glasses, use this
# utility.
#
# some great anaglyphs can be found here:
#   http://www.hq.nasa.gov/office/pao/History/alsj/a11/images11.html
#

import os
import sys

if '-r' in sys.argv:
    sys.argv.remove ('-r')
    reverse = True
else:
    reverse = False

if len(sys.argv) < 2:
    print 'Usage: unanaglyph.py <output_filename>'
    print '  stdin should be a ppm image, either 16 or 8-bit.'
else:
    name = sys.argv[1]

    # should create three files, noname.{red,grn,blu}
    os.system ('pnmdepth 255 | ppmtorgb3')

    if reverse:
        os.system ('pnmcat -lr noname.red noname.blu | cjpeg > %s.jpg' % (name,))
    else:
        os.system ('pnmcat -lr noname.blu noname.red | cjpeg > %s.jpg' % (name,))

    # throw away the temp files
    os.unlink ('noname.red')
    os.unlink ('noname.blu')
    os.unlink ('noname.grn')
    # useful on the mac
    os.system ('open %s.jpg' % (name,))