Welcome folks today in this post we will be scanning or reading qr codes and also generating qr codes in python using opencv and numpy and qrcode library. All the source code of the application is given below.
Get Started
In order to get started you need to install the following libraries
pip install qrcode
pip install opencv-python
pip install numpy
After installing all these libraries we need to create an app.py file and copy paste the following code
First of all we will be generating simple qr codes using qrcode library and numpy
app.py
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import qrcode # example data data = "https://codingshiksha.com" # output file name filename = "codingshiksha.png" # generate qr code img = qrcode.make(data) # save img to a file img.save(filename) |
Simply we are importing the qrcode library and then we are generating the simple qr code containing the website url codingshiksha.com and we have given the output file name as codingshiksha.png so when you run the python script as shown below
python app.py
You will see the qr code image being created as shown below
You can even make colored qr codes having custom border as well as shown below in the example
app.py
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import qrcode import numpy as np # data to encode data = "https://www.codingshiksha.com" # instantiate QRCode object qr = qrcode.QRCode(version=1, box_size=10, border=4) # add data to the QR code qr.add_data(data) # compile the data into a QR code array qr.make() # print the image shape print("The shape of the QR image:", np.array(qr.get_matrix()).shape) # transfer the array into an actual image img = qr.make_image(fill_color="white", back_color="red") # save it to a file img.save("codingshiksha.png") |
Now this will be a red colored qr code as shown below when you run it
Reading QR Codes
Now we will look at how to read the data which is contained inside the qr codes as shown below in the example
app.py
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import cv2 # initalize the cam cap = cv2.VideoCapture(0) # initialize the cv2 QRCode detector detector = cv2.QRCodeDetector() while True: _, img = cap.read() # detect and decode data, bbox, _ = detector.detectAndDecode(img) # check if there is a QRCode in the image if bbox is not None: # display the image with lines for i in range(len(bbox)): # draw all lines cv2.line(img, tuple(bbox[i][0]), tuple(bbox[(i+1) % len(bbox)][0]), color=(255, 0, 0), thickness=2) if data: print("[+] QR Code detected, data:", data) # display the result cv2.imshow("img", img) if cv2.waitKey(1) == ord("q"): break cap.release() cv2.destroyAllWindows() |
Here we are using the python-opencv library to read the data of qr code as shown below
