System Information

OpenCV python version: 4.7.0.72
Operating System: Ubuntu 22.04
Python version: 3.10.6

.venv dump (pip freeze) - also contains other QR detection libraries which were tested:

joblib==1.2.0numpy==1.24.3opencv-python==4.7.0.72py4j==0.10.9.7PyBoof==0.41pyzbar==0.1.9pyzxing==1.0.2segno==1.5.2six==1.16.0transforms3d==0.4.1

Detailed description

I was testing the performance of various QR code detection libraries using "perfect" version 1-H QR codes generated bysegno, and I noticed that some of these codes could not be detected. In particular, the following values failed to be detected when testing exhaustively in the range$[0, 10^6]$:

9133, 24901, 27002, 28211, 30270, 33094, 36997, 37379, 51851, 62533, 63856, 70558, 71054, 74397, 76142, 79599, 91536

This issue was not exclusive to OpenCV, and other tested libraries such asBoofCV also had issues with some payloads (although for different values), which are confirmed as a bug due to false positives in the finder pattern (which may or may not be the same issue in this case) - seelessthanoptimal/PyBoof#23. Please note that there is also an identified bug insegno in which the padding is malformed for 4-digit payloads - seeheuer/segno#123, although this does not seem to affect OpenCV as I'm assuming you ignore the padding bits (which seems to be a strategy employed by many detector libraries).

Steps to reproduce

importcv2importsegnoTEST_FILE='qr_test.png'qr_opencv=cv2.QRCodeDetector()bad_detections= []foriinrange(0,100000):qrcode=segno.make(i,version=1)assertqrcode.error=='H'qrcode.save(TEST_FILE,scale=5)img=cv2.imread(TEST_FILE)img=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)img=cv2.resize(img, (88,88))detected,points,straight_qrcode=qr_opencv.detectAndDecode(img)ifnotdetected:print(f"Unable to detect{i}")bad_detections.append(i)else:assertstr(detected)==str(i),f"Mismatch between detected value{detected} and input{x}"print(f"Unable to detect the following data payloads:\n{bad_detections}")

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)