emergent_orange.py

import os, sys
from PIL import Image

size = 128, 128
w, h = size

reds = [0] * w * h
greens = [0] * w * h
blues = [0] * w * h
count = 0

path = sys.argv[1] if len(sys.argv) > 1 else "."

try:
    for (dirpath, dirnames, filenames) in os.walk(path):
        for filename in filenames:
            if os.path.splitext(filename)[1].lower() in ('.jpg', '.png'):
                path = os.sep.join([dirpath, filename])
                try:
                    im = Image.open(path).convert("RGB").resize(size,
                        Image.ANTIALIAS)
                except IOError:
                    print "could not load", path
                    continue
                count += 1
                print "adding", path
                for i, (r, g, b) in enumerate(im.getdata()):
                    reds[i] += r
                    greens[i] += g
                    blues[i] += b
except KeyboardInterrupt:
    print

print "added", count, "images"
if count:
    def norm(channel):
        channel = [c / count for c in channel]
        mn = min(channel)
        scale = 255 * 1 / (max(channel) - mn)
        for c in channel:
            yield (c - mn) * scale
    data = bytearray([0] * w * h * 3)
    data[0::3] = norm(reds)
    data[1::3] = norm(greens)
    data[2::3] = norm(blues)
    dest = Image.frombuffer("RGB", size, buffer(data), 'raw', "RGB", 0, 1)
    dest.show()
    dest.save("emergent_orange.png")