OpenCV读取与写入图片的实现

cv2.imread(filename, flags)

cv2.imshow(winname, mat)

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imshow('img', img)
cv2.waitKey(0)

cv2.imwrite(filename, img)

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imwrite('img1.jpg', img)

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imwrite('imgTest.jpg', img, [cv2.IMWRITE_JPEG_QUALITY, 0])

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imwrite('imgTest2.jpg', img, [cv2.IMWRITE_JPEG_QUALITY, 50])

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imwrite('imgTest1.png', img)

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imwrite('imgTest2.png', img, [cv2.IMWRITE_PNG_COMPRESSION, 0])

import cv2
img = cv2.imread("img.jpg", 1)
cv2.imwrite('imgTest3.png', img, [cv2.IMWRITE_PNG_COMPRESSION, 50])

import cv2
img = cv2.imread('img.jpg', 1)
(b, g, r) = img[100, 100] # 读取像素值
print(b, g, r)
#10,100 --- 110, 100
for i in range(1, 1000):
  img[10 + i][100] = (255, 0, 0)
cv2.imshow('imageBlue.png', img)
cv2.waitKey(0)