"AI Basics" python:opencv--image processing (1)

basic operation of OPENCV Image: Using package Cv2,numpy

import cv2import numpy as npimg = cv2.imread(‘1.jpg‘)cv2.imshow(‘image‘,img)k = cv2.waitKey(0)"把一个RGB图片看成一个3维的数组"img2 = img[20:300, 100:400]cv2.imshow(‘img2‘,img2)k = cv2.waitKey(0)"快速矩阵运算是numpy的优点，批量像素修改不需要使用循环，使用矩阵运算"px=img[100,100]print(px)blue = img[100,100,0]print(blue)img[100:200,100:200]=[255,255,255]print(img[101,101])cv2.imshow(‘image‘,img)k = cv2.waitKey(0)img = cv2.imread(‘1.jpg‘)" img.shape可以获得图像的形状，返回值是一个包含行数，列数，通道数的元组"" 灰度图，返回值仅有行数和列数"print(img.shape)"img.size可以返回图像的像素数目"print(img.size)"图像的特定区域  拷贝操作"logo = img[30:130, 330:430]img[100:200,100:200] = logocv2.imshow(‘image‘,img)k = cv2.waitKey(0)"拆分及合并图像通道  对RGB三个通道分别操作""cv2.split()是比较耗时的操作，能用numpy就尽量使用"r,g,b=cv2.split(img)#拆分#img=cv2.merge(r,g,b)#合并cv2.imshow(‘b‘,b)k = cv2.waitKey(0)img[:,:,2]=0cv2.imshow(‘img‘,img)k = cv2.waitKey(0)

AI Basics python:opencv--image processing (1)