assemble_images.py

用python实现的邮件过滤器

#!/usr/bin/env python

import sys
import os
import getopt
import tempfile

import PIL.Image

def imconcatlr(left, right):
    # concatenate left and right images
    w1, h1 = left.size
    w2, h2 = right.size
    print >> sys.stderr, "lr:", (w1, h1), "+", (w2, h2)
    result = PIL.Image.new("RGB", (w1+w2, h1))
    result.paste(left, (0, 0))
    result.paste(right, (w1, 0))
    return result

def imconcattb(upper, lower):
    # concatenate upper and lower images
    w1, h1 = upper.size
    w2, h2 = lower.size
    print >> sys.stderr, "tb:", (w1, h1), "+", (w2, h2)
    result = PIL.Image.new("RGB", (w1, h1+h2))
    result.paste(upper, (0, 0))
    result.paste(lower, (0, h1))
    return result

def pnmsize(pnmfile):
    f = open(pnmfile)
    line1 = f.readline()
    line2 = f.readline()
    w, h = [int(n) for n in line2.split()]
    return w, h

def main(args):
    opts, args = getopt.getopt(args, "n")
    do_netpbm = False
    for opt, arg in opts:
        if opt == "-n":
            do_netpbm = True

    if do_netpbm:
        netpbm_assemble_images(args)
    else:
        pil_assemble_images(args)

def netpbm_assemble_images(files):
    rows = []
    n = 1
    for f in files:
        w, h = pnmsize(f)
        if not rows:
            print >> sys.stderr, "first image:", (w, h)
            rows.append([f])
        elif pnmsize(rows[-1][-1])[1] != h:
            # height differs - start a new row
            print >> sys.stderr, "last image:", pnmsize(rows[-1][-1]),
            print >> sys.stderr, "new image:", (w, h), "==> new row"
            rows.append([f])
        else:
            # append to current row
            print >> sys.stderr, "last image:", pnmsize(rows[-1][-1]),
            print >> sys.stderr, "new image:", (w, h), "==> same row"
            rows[-1].append(f)

    for (i, row) in enumerate(rows):
        if len(row) > 1:
            fd, pnmfile = tempfile.mkstemp()
            os.close(fd)
            os.system("pnmcat -lr %s > %s 2>/dev/null" %
                      (" ".join(row), pnmfile))
            for f in row:
                os.unlink(f)
            rows[i] = pnmfile
        else:
            rows[i] = row[0]

    fd, pnmfile = tempfile.mkstemp()
    os.close(fd)
    os.system("pnmcat -tb %s > %s 2>/dev/null" % (" ".join(rows), pnmfile))
    for f in rows:
        os.unlink(f)

    os.system("pnmtopng %s 2>/dev/null" % pnmfile)
    os.unlink(pnmfile)

def pil_assemble_images(files):
    rows = []
    n = 1
    for f in files:
        image = PIL.Image.open(open(f, "rb"))
        image.save(open("%d.png" % n, "wb"), "PNG")
        n += 1
        if not rows:
            # first image
            print >> sys.stderr, "first image:", image.size
            rows.append(image)
        elif image.size[1] != rows[-1].size[1]:
            # height differs - start a new row
            print >> sys.stderr, "last image:", rows[-1].size,
            print >> sys.stderr, "new image:", image.size, "==> new row"
            rows.append(image)
        else:
            # append to current row
            print >> sys.stderr, "last image:", rows[-1].size,
            print >> sys.stderr, "new image:", image.size, "==> same row"
            rows[-1] = imconcatlr(rows[-1], image)

    # now concatenate the result top-to-bottom
    full_image, rows = rows[0], rows[1:]
    for image in rows:
        full_image = imconcattb(full_image, image)

    full_image.save(sys.stdout, "PNG")

if __name__ == "__main__":
    main(sys.argv[1:])