capcha.py

import sys
import ImageEnhance
from PIL import Image
from pytesser import *
from urllib import urlretrieve

if len(sys.argv) != 2:
    print "error"
    print >>sys.stderr, "example: python", sys.argv[0], "http://zing.vn/capcha.php"
    sys.exit(1)

def get(link):
    try:
        urlretrieve(link,'captcha.png')
    except Exception:
        print 'error'

get(sys.argv[1])

img = Image.open('captcha.png')
img = img.convert("RGBA")

pixdata = img.load()


for y in xrange(img.size[1]):
    for x in xrange(img.size[0]):
        if pixdata[x, y][0] < 90:
            pixdata[x, y] = (0, 0, 0, 255)

for y in xrange(img.size[1]):
    for x in xrange(img.size[0]):
        if pixdata[x, y][1] < 136:
            pixdata[x, y] = (0, 0, 0, 255)

for y in xrange(img.size[1]):
    for x in xrange(img.size[0]):
        if pixdata[x, y][2] > 0:
            pixdata[x, y] = (255, 255, 255, 255)

img.save("input-black.gif", "GIF")

im_orig = Image.open('input-black.gif')
big = im_orig.resize((1000, 500), Image.NEAREST)

ext = ".tif"
big.save("input-NEAREST" + ext)

image = Image.open('input-NEAREST.tif')

print image_to_string(image)