Python OpenCV | cv2.rectangle() method

OpenCV-Python is a library of Python bindings designed to solve computer vision problems. cv2.rectangle() method is used to draw a rectangle on any image.

Syntax: cv2.rectangle(image, start_point, end_point, color, thickness)

Parameters:
image: It is the image on which rectangle is to be drawn.
start_point: It is the starting coordinates of rectangle. The coordinates are represented as tuples of two values i.e. (X coordinate value, Y coordinate value).
end_point: It is the ending coordinates of rectangle. The coordinates are represented as tuples of two values i.e. (X coordinate value, Y coordinate value).
color: It is the color of border line of rectangle to be drawn. For BGR, we pass a tuple. eg: (255, 0, 0) for blue color.
thickness: It is the thickness of the rectangle border line in px. Thickness of -1 px will fill the rectangle shape by the specified color.

Return Value: It returns an image.

Image used for all the below examples:

Example #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)

Output:

Example #2:

Using thickness of -1 px to fill the rectangle by black color.

# 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)

Output: