CV2 package has imwrite() function that saves an image object to a specified file.

The command to save an image with the help of imwrite() function is as follows −

cv2.imwrite(filename, img)

The image format is automatically decided by OpenCV from the file extension. OpenCV supports *.bmp, *.dib , *.jpeg, *.jpg, *.png,*.webp, *.sr,*.tiff, *.tif etc. image file types.

Example

Following program loads OpenCV logo image and saves its greyscale version when ‘s’ key is pressed −

import numpy as np
import cv2
# Load an color image in grayscale
img = cv2.imread(''OpenCV_Logo.png'',0)
cv2.imshow(''image'',img)
key=cv2.waitKey(0)
if key==ord(''s''):
   cv2.imwrite("opencv_logo_GS.png", img)
cv2.destroyAllWindows()

Output