#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
#Copyright (C) 2009 kingzero, RaNaN
#
#This program is free software; you can redistribute it and/or modify
#it under the terms of the GNU General Public License as published by
#the Free Software Foundation; either version 3 of the License,
#or (at your option) any later version.
#
#This program is distributed in the hope that it will be useful,
#but WITHOUT ANY WARRANTY; without even the implied warranty of
#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#See the GNU General Public License for more details.
#
#You should have received a copy of the GNU General Public License
# along with this program; if not, see <http://www.gnu.org/licenses/>.
#
###
import logging
import subprocess
import tempfile
import threading
import Image
class RunThread(threading.Thread):
def __init__(self):
threading.Thread.__init__(self)
def e(self, command, inputdata=None):
"""execute command """
self.command = command
self.inputdata = inputdata
self.result = ""
self.start()
self.join(10)
return self.result
def run(self):
"""Run a command and return standard output"""
pipe = subprocess.PIPE
popen = subprocess.Popen(self.command, stdout=pipe, stderr=pipe)
outputdata, errdata = popen.communicate(self.inputdata)
assert (popen.returncode == 0), \
"Error running: %s\n\n%s" % (self.command, errdata)
self.result = outputdata
class OCR(object):
def __init__(self):
self.logger = logging.getLogger("log")
def load_image(self, image):
self.image = Image.open(image)
self.pixels = self.image.load()
self.result_captcha = ''
def unload(self):
"""delete all tmp images"""
pass
def threshold(self, value):
self.image = self.image.point(lambda a: a * value + 10)
def run(self, command, inputdata=None):
"""Run a command and return standard output"""
# OLD METHOD
# pipe = subprocess.PIPE
# popen = subprocess.Popen(command, stdout=pipe, stderr=pipe)
# outputdata, errdata = popen.communicate(inputdata)
# assert (popen.returncode == 0), \
# "Error running: %s\n\n%s" % (command, errdata)
# return outputdata
thread = RunThread()
result = thread.e(command, inputdata)
return result
def run_gocr(self):
tmp = tempfile.NamedTemporaryFile(suffix=".jpg")
self.image.save(tmp)
self.result_captcha = self.run(['gocr', tmp.name]).replace("\n", "")
def run_tesser(self):
tmp = tempfile.NamedTemporaryFile(suffix=".tif")
tmpTxt = tempfile.NamedTemporaryFile(suffix=".txt")
self.image.save(tmp.name, 'TIFF')
self.run(['tesseract', tmp.name, tmpTxt.name.replace(".txt", "")])
self.result_captcha = self.run(['cat', tmpTxt.name]).replace("\n", "")
def get_captcha(self):
raise NotImplementedError
def to_greyscale(self):
if self.image.mode != 'L':
self.image = self.image.convert('L')
self.pixels = self.image.load()
def eval_black_white(self, limit):
self.pixels = self.image.load()
w, h = self.image.size
for x in xrange(w):
for y in xrange(h):
if self.pixels[x, y] > limit:
self.pixels[x, y] = 255
else:
self.pixels[x, y] = 0
def clean(self, allowed):
pixels = self.pixels
w, h = self.image.size
for x in xrange(w):
for y in xrange(h):
if pixels[x, y] == 255: continue
# no point in processing white pixels since we only want to remove black pixel
count = 0
try:
if pixels[x-1, y-1] != 255: count += 1
if pixels[x-1, y] != 255: count += 1
if pixels[x-1, y + 1] != 255: count += 1
if pixels[x, y + 1] != 255: count += 1
if pixels[x + 1, y + 1] != 255: count += 1
if pixels[x + 1, y] != 255: count += 1
if pixels[x + 1, y-1] != 255: count += 1
if pixels[x, y-1] != 255: count += 1
except:
pass
# not enough neighbors are dark pixels so mark this pixel
# to be changed to white
if count < allowed:
pixels[x, y] = 1
# second pass: this time set all 1's to 255 (white)
for x in xrange(w):
for y in xrange(h):
if pixels[x, y] == 1: pixels[x, y] = 255
self.pixels = pixels
def derotate_by_average(self):
"""rotate by checking each angle and guess most suitable"""
w, h = self.image.size
pixels = self.pixels
for x in xrange(w):
for y in xrange(h):
if pixels[x, y] == 0:
pixels[x, y] = 155
highest = {}
counts = {}
for angle in range(-45, 45):
tmpimage = self.image.rotate(angle)
pixels = tmpimage.load()
w, h = self.image.size
for x in xrange(w):
for y in xrange(h):
if pixels[x, y] == 0:
pixels[x, y] = 255
count = {}
for x in xrange(w):
count[x] = 0
for y in xrange(h):
if pixels[x, y] == 155:
count[x] += 1
sum = 0
cnt = 0
for x in count.values():
if x != 0:
sum += x
cnt += 1
avg = sum / cnt
counts[angle] = cnt
highest[angle] = 0
for x in count.values():
if x > highest[angle]:
highest[angle] = x
highest[angle] = highest[angle] - avg
hkey = 0
hvalue = 0
for key, value in highest.iteritems():
if value > hvalue:
hkey = key
hvalue = value
self.image = self.image.rotate(hkey)
pixels = self.image.load()
for x in xrange(w):
for y in xrange(h):
if pixels[x, y] == 0:
pixels[x, y] = 255
if pixels[x, y] == 155:
pixels[x, y] = 0
self.pixels = pixels
def split_captcha_letters(self):
captcha = self.image
started = False
letters = []
width, height = captcha.size
bottomY, topY = 0, height
pixels = captcha.load()
for x in xrange(width):
black_pixel_in_col = False
for y in xrange(height):
if pixels[x, y] != 255:
if started == False:
started = True
firstX = x
lastX = x
if y > bottomY: bottomY = y
if y < topY: topY = y
if x > lastX: lastX = x
black_pixel_in_col = True
if black_pixel_in_col == False and started == True:
rect = (firstX, topY, lastX, bottomY)
new_captcha = captcha.crop(rect)
w, h = new_captcha.size
if w > 5 and h > 5:
letters.append(new_captcha)
started = False
bottomY, topY = 0, height
return letters
def correct(self, values, var=None):
if var:
result = var
else:
result = self.result_captcha
for key, item in values.iteritems():
if key.__class__ == str:
result = result.replace(key, item)
else:
for expr in key:
result = result.replace(expr, item)
if var:
return result
else:
self.result_captcha = result
if __name__ == '__main__':
ocr = OCR()
ocr.load_image("B.jpg")
ocr.to_greyscale()
ocr.eval_black_white(140)
ocr.derotate_by_avergage()
ocr.run_gocr()
print "GOCR", ocr.result_captcha
ocr.run_tesser()
print "Tesseract", ocr.result_captcha
ocr.image.save("derotated.jpg")