

Detect and Decode QR Code in Image using OpenCV and Python
QR code is a two-dimensional barcode which stores encoded data. It can be a website URL, contact details, location coordinates, email address, plain text, etc. QR code can store more data than a linear barcode of equal size.
This tutorial provides example how detect and decode a QR code in image using OpenCV and Python.
Using pip
package manager install opencv-python
from the command line.
pip install opencv-python
We create an object of class QRCodeDetector
. QR code is detected and decoded by using detectAndDecode
method. It returns a tuple of values:
- Decoded data.
- An array of vertices of the found QR code.
- An image that contains processed and binarized QR code.
import cv2 image = cv2.imread('test.jpg') qrCodeDecoder = cv2.QRCodeDetector() decodedData, points, straightQrCode = qrCodeDecoder.detectAndDecode(image) if points is not None: print('Decoded data: ' + decodedData) points = points[0] n = len(points) for i in range(n): point1 = points[i] point2 = points[(i + 1) % n] cv2.line(image, tuple(point1), tuple(point2), color=(255, 0, 0), thickness=3) cv2.imshow('Detected QR Code', image) cv2.waitKey(0) cv2.destroyAllWindows()
If a QR code was found we print the decoded data and draw a bounding box around the detected QR Code.
Decoded data: https://lindevs.com
