Building a QR Code Attendance System

July 2025 Dharshan V 8 min read

In this comprehensive guide, I'll show you how to build a QR Code Attendance System using Python, OpenCV, and MySQL. This project combines computer vision, database management, and GUI development.

Project Overview

The QR Code Attendance System automates the process of tracking student or employee attendance by scanning QR codes. Here's what we'll build:

QR Code Scanner

Real-time QR code detection using OpenCV and webcam integration.

Database Management

Store attendance records in MySQL with student information and timestamps.

GUI Interface

User-friendly interface built with Tkinter for easy operation.

Required Libraries

pip install opencv-python
pip install mysql-connector-python
pip install qrcode
pip install pillow
pip install tkinter

Key Features

Real-time QR Detection: Instant scanning and recognition of QR codes
Database Integration: Automatic storage of attendance records
User Management: Add, edit, and manage student/employee profiles
Attendance Reports: Generate detailed attendance reports and analytics
Export Functionality: Export attendance data to CSV/Excel formats

Implementation Steps

1. Database Setup

First, create the MySQL database and tables for storing attendance data.

CREATE DATABASE attendance_system;
USE attendance_system;

CREATE TABLE students (
    id INT PRIMARY KEY AUTO_INCREMENT,
    student_id VARCHAR(20) UNIQUE,
    name VARCHAR(100),
    email VARCHAR(100),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE attendance (
    id INT PRIMARY KEY AUTO_INCREMENT,
    student_id VARCHAR(20),
    check_in TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    check_out TIMESTAMP NULL,
    FOREIGN KEY (student_id) REFERENCES students(student_id)
);

2. QR Code Generation

Generate unique QR codes for each student containing their ID.

import qrcode
import os

def generate_qr_code(student_id, name):
    qr = qrcode.QRCode(version=1, box_size=10, border=5)
    qr.add_data(student_id)
    qr.make(fit=True)
    
    img = qr.make_image(fill_color="black", back_color="white")
    filename = f"qr_codes/{student_id}_{name}.png"
    img.save(filename)
    return filename

3. QR Code Scanner

Implement real-time QR code scanning using OpenCV.

import cv2
from pyzbar import pyzbar

def scan_qr_code():
    cap = cv2.VideoCapture(0)
    
    while True:
        ret, frame = cap.read()
        barcodes = pyzbar.decode(frame)
        
        for barcode in barcodes:
            student_id = barcode.data.decode('utf-8')
            # Process attendance
            mark_attendance(student_id)
            
        cv2.imshow('QR Scanner', frame)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break
    
    cap.release()
    cv2.destroyAllWindows()

Pro Tips

• Use threading to prevent GUI freezing during scanning
• Implement error handling for database connections
• Add logging for debugging and monitoring
• Consider adding face recognition for additional security