[Python] The result obtained from the OpenCV-Python cv.add() function differs from the...

During my learning process of OpenCV-Python, I encountered an issue. My environment uses Python version 3.13, NumPy version 2.2.6, and OpenCV-Python version 4.12.

In the "Arithmetic Operations on Images" section of the official documentation, it mentions the difference between OpenCV addition and NumPy addition: OpenCV addition is a saturated operation while NumPy addition is a modulo operation. Official documentation page

However, the actual results I obtained during computation differ from the values provided in the documentation.

My code:

import cv2 as cv
import numpy as np

x = np.uint8([250])
y = np.uint8([10])

print(f"x+y = {x+y}")
print(f"cv.add(x,y) = {cv.add(x,y)}")


Official documentation result:

[4]
[[255]]


My result:

[4]
[[260.]
[0.]
[0.]
[0.]]


I checked cv.add(x,y).dtype and found it returns float64 instead of uint8.

After attempting data type conversion and retrieving the first value with cv.add(x,y).astype(np.uint8)[0], the result is [4], which matches the NumPy addition result. How can I obtain the correct value from the cv.add() algorithm?

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