Opencv从入门到精通（四）：在图像上画线/矩形/圆/文字

import cv2
import numpy as np

img = np.ones(shape=(512,512,3))# HWCprint(img.dtype)# img[:] = 255, 0, 0 # 整个图像变为蓝色# 画直线# cv2.line(img, (0, 0), (100, 100), color=(0, 255, 0), thickness=3) # 画对角线
cv2.line(img,(0,0),(img.shape[1], img.shape[0]), color=(0,255,0), thickness=3)# 画矩形 cv2.FILLED填满
cv2.rectangle(img,(0,0),(200,100), color=(0,0,255), thickness=cv2.FILLED)# 画圆
cv2.circle(img,(100,50),30,(255,0,0))# 写文字 fontScale：字体比例
cv2.putText(img,' OPEN CV ', org=(300,100), fontFace=cv2.FONT_ITALIC, fontScale=0.5, color=(0,0,255), thickness=3)

cv2.imshow('Img', img)
cv2.waitKey(0)