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\neveropen\Lazyroar.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\neveropen\Lazyroar.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: