Python OpenCV – getWindowImageRect() Function

Python OpenCV getWindowImageRect() Function returns the client screen coordinates, along with the width and height of the window containing the picture.

Syntax of cv2.getWindowImageRect()

Syntax: cv2.getWindowImageRect(window_name)

Parameter:

• window_name – Name of the window displaying image/video

Return: return a tuple of x, y, w, h(Set of four integers including the coordinates & size of rectangle)with window name. 

Image for Demonstration:

Example 1: Get default window size using getWindowImageRect() Python

• In the mentioned code, the Python OpenCV library is imported.The path variable stores the filepath of the image from the local machine.
• The imread() method is used in default mode to load the given file from the path into the image variable.
• To use the getWindowImageRect() function, we need to create a window first using the namedWindow() method and the default flag value is used.
• The dimensions and coordinates returned by the getWindowImageRect() function of the created window is printed on the console. The returned values can also be assigned separately and printed.
• The created window is displayed to the user using the imshow() method. After the wait time (here 0 ms), the user can destroy all the windows by pressing any key from the keyboard.

Python3

# Importing OpenCV
import cv2

# Path to image
path = 'C:/Users/Amisha Kirti/Downloads/GFG.png'

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

# Creating window with name "Display1"
# of default size
cv2.namedWindow("Display1", cv2.WINDOW_AUTOSIZE)

# Using getWindowImageRect()
print(cv2.getWindowImageRect("Display1"))

# Assigning the returned values to variables
(x, y, windowWidth, windowHeight) = cv2.
getWindowImageRect("Display1")

"""
We can also assign values to variables by
accessing returned value by index

x = cv2.getWindowImageRect("Display1")[0]
y = cv2.getWindowImageRect("Display1")[1]
windowWidth=cv2.getWindowImageRect("Display1")[2]
windowHeight=cv2.getWindowImageRect("Display1")[3]
"""

print("Origin Coordinates(x,y): ", x, y)
print("Width: ", windowWidth)
print("Height: ", windowHeight)

# Displaying the image using imshow
cv2.imshow('Display1', image)

# Waiting 0ms for user to press any key
cv2.waitKey(0)

# Destroying all windows open on screen
cv2.destroyAllWindows()

Output:

Example-1 Console & Window Output

Example 2: Get fullscreen window size using getWindowImageRect() Python

This function helps us get the exact number of pixels of the window in which the image is displayed.

• One can create a window in full-screen mode and get its width and height
• To use the getWindowImageRect() function, we need to create a window first using the namedWindow() method. In this example the WINDOW_FULLSCREEN or WINDOW_NORMAL flag value is used.

Python3

# Importing OpenCV
import cv2

# Path to image [NOTE: Here resized image
# is used to be able to fit to screen]
path = 'download3.png'

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

# Creating a full screen window with
# name "Display2" using WINDOW_FULLSCREEN
# or WINDOW_NORMAL
cv2.namedWindow("Display2", cv2.WINDOW_NORMAL)

# Using getWindowImageRect()
print(cv2.getWindowImageRect("Display2"))

# Assigning the returned values to variables
(x, y, windowWidth, windowHeight) = cv2.
        getWindowImageRect("Display2")

print("Origin Coordinates(x,y): ", x, y)
print("Width: ", windowWidth)
print("Height: ", windowHeight)

# Displaying the image using imshow
cv2.imshow('Display2', image)

# Waiting 0ms for user to press any key
cv2.waitKey(0)

# Destroying all created windows
# open on screen
cv2.destroyAllWindows()

Output:

Example-2 Window Output

Example-2 Console Output