System Information

OpenCV version: 4.2.0+dfsg-5 from Ubuntu 20.04 and 4.5.4 from Nix latest.
Operating System: Ubuntu 20.04 on AMD Ryzen 7 5700G
Python version: 3.8.10 from Ubuntu 20.04 and 3.10.8 from Nix latest.

Detailed description

We get a segmentation fault calling QRCodeDetector.detectAndDecodeCurved for some images:

$ PYTHONFAULTHANDLER=1 python3 crash_repo.py
Fatal Python error: Segmentation fault

Current thread 0x00007fd41ab83740 (most recent call first):
  File "/xxx/crash_repo.py", line 5 in <module>

Extension modules: numpy.core._multiarray_umath, numpy.core._multiarray_tests, numpy.linalg._umath_linalg, numpy.fft._pocketfft_internal, numpy.random._common, numpy.random.bit_generator, numpy.random._bounded_integers, numpy.random._mt19937, numpy.random.mtrand, numpy.random._philox, numpy.random._pcg64, numpy.random._sfc64, numpy.random._generator, cv2 (total: 14)
Segmentation fault (core dumped)

This happens infrequently but with a given image it is 100% reproducible.

Seems similar to #19626 but they want a new issue over there.

Steps to reproduce

Run the following minimal code:

import cv2 as cv

img = cv.imread("last_qr.png")
qcd = cv.QRCodeDetector()
qcd.detectAndDecodeCurved(img)

This file triggers it:

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)