opencv imwrite

The function `cv2.imwrite()` is used to write an image to a file in OpenCV.

Syntax:

`cv2.imwrite(filename, img[, params])`

Parameters:

- **filename**: Name of the file to be saved. The file extension should be supported by OpenCV.
- **img**: The numpy array containing the image to be saved.
- **params**: The optional parameters to be passed to the file writer.

Return Value:

The function returns true if the image is saved successfully, otherwise false.

Example:

import cv2

# Read an image
img = cv2.imread('image.jpg')

# Save the image
cv2.imwrite('saved_image.jpg', img)

In the above example, we first read an image using `cv2.imread()` and then save it using `cv2.imwrite()`. The saved image will be in the same directory as the program.