python 二值化代码_Python图像处理二值化方法实例汇总

在用python进行图像处理时，二值化是非常重要的一步，现总结了自己遇到过的6种 图像二值化的方法(当然这个绝对不是全部的二值化方法，若发现新的方法会继续新增)。

1. opencv 简单阈值 cv2.threshold

2. opencv 自适应阈值 cv2.adaptiveThreshold (自适应阈值中计算阈值的方法有两种：mean_c 和 guassian_c ，可以尝试用下哪种效果好)

3. Otsu's 二值化

例子:

import cv2

import numpy as np

from matplotlib import pyplot as plt

img = cv2.imread('scratch.png', 0)

# global thresholding

ret1, th1 = cv2.threshold(img, 127, 255, cv2.THRESH_BINARY)

# Otsu's thresholding

th2 = cv2.adaptiveThreshold(img, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY, 11, 2)

# Otsu's thresholding

# 阈值一定要设为 0 !

ret3, th3 = cv2.threshold(img, 0, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)

# plot all the images and their histograms

images = [img, 0, th1, img, 0, th2, img, 0, th3]

titles = [

'Original Noisy Image', 'Histogram', 'Global Thresholding (v=127)',

'Origi