pyzbar is a QR code and Barcode decoder library available in python. It can detect multiple codes from one image and return the code type. OpenCV 4.1 also has QR code detector called QRCodeDetector but it can only detect one QR code from image and barcode is not supported, which is not as powerful as pyzbar.
Test environment: Python 3.6 with OpenCV4.1 and pyzbar 0.1.8
Python Code is below:
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