验证码识别

#coding:utf-8
import urllib2
from PIL import Image
from PIL import ImageFilter
import os,sys

def getImage():
        '''网上获取图片'''
    global time,pixels
    url = ''
    fname = 'validatecode.bmp'
    open(fname,'wb').write(urllib2.urlopen(url).read())
    img = Image.open(fname).convert('L')
    return img
    
def getMatrix(i):
        '''把模板文件读入数组'''
    global cache,time
    if i in cache.keys():
        return cache[i]
    arr = [[0 for col in range(6)] for row in range(10)]
    f = open('%d.txt'%i)
    for y in range(10):
        l = f.readline()
        for x in range(6):
            arr[y][x] = int(l[x])
    cache[i] = arr
    return arr

def recognize(img,i):
        '''返回img和数字i的识别率rate'''
    rate = 0
    arr = img.load()    
    for x in range(6):
        for y in range(10):
            if arr[x,y]<128 and getMatrix(i)[y][x]==0:
                rate += 1
            elif arr[x,y]>128 and getMatrix(i)[y][x]==1:
                rate += 1
    return rate

os.chdir('./')
cache = {}
img = getImage()

left = 7
up = 5
right = 13
down = 15
for i in range(4):
    #把图片切割成仅容下数字的四个图片
    im = img.crop((left,up,right,down))

    #下面8行是识别过程
    rec_n = -1
    rec_rate = -1
    for n in range(10):
        t = recognize(im,n)
        if t > rec_rate:
            rec_n = n
            rec_rate = t
    sys.stdout.write('%d'%rec_n)

    #下面注释行是学习过程
    #im.save('%d.bmp'%i)
    #txt = open('%d.try.txt'%i,'w')
    #arr = im.load()
    #for y in range(10):
        #for x in range(6):
            #if arr[x,y] > 128:
                #txt.write('1')    
            #else:
                #txt.write('0')
        #txt.write(os.linesep)
    #txt.close()

    left += 13
    right += 13

print ' '
raw_input('Press enter key to continue...')


首先把学习过程解注释掉，并运行学习过程，这样会在同目录下生成1.bmp：1.try.txt    2.bmp：2.try.txt   3.bmp：3.try.txt    4.bmp：4.try.txt四对文件，*.bmp的模板文件是*.try.txt，将*.try.txt改成*.bmp的字样数字（比如*.bmp的字样是数字5，就把*.try.txt改成5.txt）。重复上面的过程，知道0.txt   1.txt  ....  9.txt都有了，这样模板就识别完毕。
然后运行识别过程就可以了。