二值化代码

#coding:utf-8
#图像二值处理
import os

from PIL import Image
j=1
dirpath="./pic/"
path = "./font/"

img = Image.open('D:\mobile\hi.bmp') # 读入图片
img = img.convert("RGBA")
pixdata = img.load()
#二值化
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('D:\mobile\hi2.png')

　参考链接：http://vipscu.blog.163.com/blog/static/18180837220134234528457/