Python OpenCV | cv2.rectangle()方法

原文:https://www . geesforgeks . org/python-opencv-cv2-rectangle-method/

OpenCV-Python 是一个 Python 绑定库,旨在解决计算机视觉问题。cv2.rectangle()方法用于在任意图像上绘制矩形。

语法: cv2 .矩形(图像、起点、终点、颜色、厚度)

参数: 图像:就是要画矩形的图像。 起点:是矩形的起始坐标。坐标表示为两个值的元组(即 X 坐标值、 Y 坐标值)。 end_point: 是矩形的结束坐标。坐标表示为两个值的元组(即 X 坐标值, Y 坐标值)。 颜色:是待画矩形边框线的颜色。对于 BGR ,我们传递一个元组。例如:(255,0,0)代表蓝色。 厚度:px 中矩形边框线的厚度。 -1 px 的厚度会以指定的颜色填充矩形。

返回值:返回图像。

图像用于以下所有示例:

示例#1:

# Python program to explain cv2.rectangle() method 

# importing cv2 
import cv2 

# path 
path = r'C:\Users\Rajnish\Desktop\geeksforgeeks\geeks.png'

# Reading an image in default mode
image = cv2.imread(path)

# Window name in which image is displayed
window_name = 'Image'

# Start coordinate, here (5, 5)
# represents the top left corner of rectangle
start_point = (5, 5)

# Ending coordinate, here (220, 220)
# represents the bottom right corner of rectangle
end_point = (220, 220)

# Blue color in BGR
color = (255, 0, 0)

# Line thickness of 2 px
thickness = 2

# Using cv2.rectangle() method
# Draw a rectangle with blue line borders of thickness of 2 px
image = cv2.rectangle(image, start_point, end_point, color, thickness)

# Displaying the image 
cv2.imshow(window_name, image) 

输出:

例 2:

使用-1 像素的厚度用黑色填充矩形。

# Python program to explain cv2.rectangle() method 

# importing cv2 
import cv2 

# path 
path = r'C:\Users\Rajnish\Desktop\geeksforgeeks\geeks.png'

# Reading an image in grayscale mode
image = cv2.imread(path, 0)

# Window name in which image is displayed
window_name = 'Image'

# Start coordinate, here (100, 50)
# represents the top left corner of rectangle
start_point = (100, 50)

# Ending coordinate, here (125, 80)
# represents the bottom right corner of rectangle
end_point = (125, 80)

# Black color in BGR
color = (0, 0, 0)

# Line thickness of -1 px
# Thickness of -1 will fill the entire shape
thickness = -1

# Using cv2.rectangle() method
# Draw a rectangle of black color of thickness -1 px
image = cv2.rectangle(image, start_point, end_point, color, thickness)

# Displaying the image 
cv2.imshow(window_name, image) 

输出: