concat images

conat-images.py

import Image
import sys

def concat(images, wfn, hfn, xm, ym):
    width = wfn(im.size[0] for im in images)
    height = hfn(im.size[1] for im in images)
    result = Image.new(images[0].mode, (width, height))
    x = y = 0
    for im in images:
        print im.size
        result.paste(im, (x, y))
        x += im.size[0] * xm
        y += im.size[1] * ym
    return result

def concat_horizontal(images): return concat(images, sum, max, 1, 0)
def concat_vertical(images): return concat(images, max, sum, 0, 1)

if __name__ == '__main__':
    mode = sys.argv[1]
    input_filenames = sys.argv[2:-1]
    result_filename = sys.argv[-1]
    input_images = [Image.open(fn) for fn in input_filenames]

    if mode == '-h':
        result = concat_horizontal(input_images)
    elif mode == '-v':
        result = concat_vertical(input_images)
    else:
        assert False, 'Mode should be given (-h or -v): %s <mode> <input1> <input2> <input3> ... <output>' % sys.argv[0]
    result.save(result_filename)