python3 使用opencv 画基本图形

在Python3 环境下安装opencv-python 后练习画基本图形:

import numpy as np

import cv2

# BGR format

GREEN     = (0, 255, 0)

RED     = (0, 0, 255)

BLUE     = (255, 0, 0)

WHITE    = (255,255,255)

canvas = np.zeros((300,300,3), dtype = "uint8")

# 画线,框,⚪

cv2.line(canvas,(0,0), (300,300), GREEN, 2)

# cv2.imshow("Canvas", canvas)

cv2.rectangle(canvas,(10,10), (60,60),GREEN, 1)

cv2.rectangle(canvas,(300,0), (0,300),RED,5)

cv2.rectangle(canvas, (200,55), (55,200), BLUE, -1)

(cx, cy) = (canvas.shape[1]/2, canvas.shape[0]/2)

for r in range(0, 200, 25):

    print(cx,cy,r)

    cv2.circle(canvas, (int(cx), int(cy)), r, WHITE)

cv2.imshow('Canvas', canvas)

cv2.waitKey(0)

canvas = np.zeros((300,300,3), dtype = "uint8")

# 随机画⚪

for i in range(0, 25):

    r = np.random.randint(5, 200)

    color = np.random.randint(0, high = 256, size = (3,)).tolist()

    pt = np.random.randint(0, high = 300, size = (2,))

    print(r)

    print("*" * 25)

    print(color)

    print("*" * 25)

    print(pt)

    cv2.circle(canvas, tuple(pt), r, color, -1)

cv2.imshow("Canvas", canvas)

cv2.waitKey(0)

运行后可看到以下效果.