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

Detailed description

I was testing the performance of various QR code detection libraries using "perfect" version 1-H QR codes generated by segno, 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 as BoofCV 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) - see lessthanoptimal/PyBoof#23. Please note that there is also an identified bug in segno in which the padding is malformed for 4-digit payloads - see heuer/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

import cv2
import segno

TEST_FILE = 'qr_test.png'

qr_opencv = cv2.QRCodeDetector()
bad_detections = []

for i in range(0, 100000):
    qrcode = segno.make(i, version=1)
    assert qrcode.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)
    if not detected:
        print(f"Unable to detect {i}")
        bad_detections.append(i)
    else:
        assert str(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)