OpenCV之二值化處理

二值化處理將使用到OpenCV中提供的閾值（threshold）函數：

cv2.threshold（灰度圖，閾值，設定值，方法）

其中方法有五個，如下：cv2.THRESH_BINARY、cv2.THRESH_BINARY_INV、cv2.THRESH_TRUNC、cv2.THRESH_TOZERO、cv2.THRESH_TOZERO_INV

# -*- coding: utf-8 -*-"""Created on Fri Sep 22 21:54:34 2017@author: shigan"""import cv2#相對路徑下讀取圖片doge = cv2.imread(doge.jpg)#灰度化處理grayImage = cv2.cvtColor(doge,cv2.COLOR_BGR2GRAY)#cv2.imshow(GRAY,grayImage)#二值化處理，低於閾值的像素點灰度值置為0；高於閾值的值置為參數3ret,thresh1 = cv2.threshold(grayImage,127,255,cv2.THRESH_BINARY)cv2.imshow(BINARY,thresh1)#大於閾值的像素點灰度值置為0；小於閾值置為參數3ret,thresh2 = cv2.threshold(grayImage,127,200,cv2.THRESH_BINARY_INV)cv2.imshow(BINARY_INV,thresh2)#小於閾值的像素點灰度值不變，大於閾值的像素點置為該閾值ret,thresh3 = cv2.threshold(grayImage,127,255,cv2.THRESH_TRUNC)cv2.imshow(TRUNC,thresh3)#小於閾值的像素點灰度值不變，大於閾值的像素點置為0,其中參數3任取ret,thresh4 = cv2.threshold(grayImage,127,255,cv2.THRESH_TOZERO)cv2.imshow(BINARY_TOZERO,thresh4)#大於閾值的像素點灰度值不變，小於閾值的像素點置為0,其中參數3任取ret,thresh5 = cv2.threshold(grayImage,127,255,cv2.THRESH_TOZERO_INV)cv2.imshow(BINARY_TOZERO_INV,thresh5)

原圖：

BINARY:

BINARY_INV:

TRUNC:

TOZERO:

TOZERO_INV:

歡迎交流

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