Python Project : How to Create a QR Code using Python?

Creating a QR Code in Python: A Step-by-Step Guide

QR codes have become a widely accepted means of sharing information in a flash-from URLs to contact details to even payment links. Creating a QR code programmatically is something useful both for developers and owners of businesses alike. In this article, we will go through how to create a QR code using Python in just a few easy steps.

Why Python for Generating QR Codes?

Python, being the center of several useful libraries, makes it extremely easy to work with the generation of QR codes. The main library that we are going to use is qrcode. This allows us to do something as complex as generating a QR code with just a handful of lines of code. It's lightweight, efficient in its implementation, and customizable. Hence, it's one of the best options to work with for generating QR codes.

How to Generate QR Code Using Python: Step-by-Step Guide

Prerequisites :

Before you begin, you'll need to have Python installed on your machine (version 3 or greater), along with pip, Python's package installer. If you don't yet have Python installed you can download it here.

Step 1: Installing Dependencies

The qrcode library is not a standard library in Python, so we should install it. You can also install the Pillow library for handling images.

Open your terminal or command prompt and write this command:

pip install qrcode[pil]
    

This command will install the qrcode library and the Pillow library for image manipulation.

Step 2: Writing Python Script to Generate QR Code

Once the library is installed, you are ready to create a Python script to generate a QR code. Below is a simple script that will develop any URL or string-based QR code.

import qrcode

# Data to encode in the QR code
data = "https://www.example.com"

# Create a QRCode object with custom settings
qr = qrcode.QRCode(
    version=1,  # Controls the size of the QR code (1-40)
    error_correction=qrcode.constants.ERROR_CORRECT_L,  # Controls error correction (L, M, Q, H)
    box_size=10,  # Size of each box in the QR code grid
    border=4,  # Thickness of the border
)

# Add data to the QRCode object
qr.add_data(data)
qr.make(fit=True)  # Adjust the dimensions automatically to fit the data

# Generate the QR code as an image
img = qr.make_image(fill='black', back_color='white')

# Save the generated QR code to a file
img.save("qrcode.png")
    

Explanation of the Code:

Data to encode: In this example, we are encoding the URL https://www.example.com. You can replace it with any other string or data you want to store in the QR code.

QR Code object: the QR Code object takes some parameters that determine the size, error correction level and border of the QR code. You might want to play around with those depending on your needs.

Error correction: This determines how much of the code can be restored if parts of the QR code get damaged. There are four levels:

L (Low) - Up to 7% error correction.

M = Medium: Up to 15% correction

Q = Quartile: Up to 25% correction

H = High: Up to 30% correction

Creating an Image: This function, make_image, populates the QR code image. For filling color and background color, we have set it to a black QR code on a white background.

Step 3: Styling the QR Code (Optional)

You can also make this simple script more useful by modifying the appearance of your QR code - such as adjusting color or embedding a logo. Example:

img = qr.make_image(fill_color="blue", back_color="yellow")
img.save("custom_qrcode.png")
    

This will create a blue-foreground, yellow-background QR code.

Step 4: Scanning the QR Code

After execution, you should see a QR code image saved in your current working directory as qrcode.png. One could then verify that indeed it was a well and truly valid code pointing to the correct URL by using any QR scanning app with their smartphones.

Use Cases for QR Code

Marketing: used to direct users to a website, landing page, or app download.

Payments: Most online platforms are making use of QR codes while doing payments.

Networking: Physically make it easy to share your contact details by embedding vCards into QR codes.

 Access Control: Give secure location or document access to selected individuals via QR codes.

Generating QR codes in Python is straightforward and, at the same time, very powerful. For any developer aiming to integrate QR codes into the application and for an entrepreneur willing to speed up customer engagement, this approach offers a solution in a very fast and tailored way.

If you followed the steps above, you now can create your own QR codes for different purposes. The qrcode library is powerful in Python, so you may explore more features than what has been described here, such as dynamic QR code generation and logo embedding.

Happy Coding!