System Information

There is no system error message, but the generated results are not as expected in the mathematical derivation. （Poisson Editing）

Detailed description

While implementing Poisson editing with this function：cv2.seamlessClone(src, dst, mask, center, cv2.MIXED_CLONE), I found unexpected shifts: the source image would be shifted a little to the top left or bottom right in the target image. This makes me confused. Is it intentional? According to my understanding of Poisson editing, there should be no such shift. The more natural fusion of Poisson editing does not lead to shifts.

Steps to reproduce

import cv2
src = cv2.imread("xxxxx")
dst = cv2.imread("xxxxx")
mask = cv2.imread("xxxxx")
center = (x,x)
output = cv2.seamlessClone(src, dst, mask, center,cv2.MIXED_CLONE) # a shift in the output

Issue submission checklist

• I report the issue, it's not a question
• I checked the problem with documentation, FAQ, open issues, forum.opencv.org, Stack Overflow, etc and have not found any solution
• I updated to the latest OpenCV version and the issue is still there
• There is reproducer code and related data files (videos, images, onnx, etc)