PHP QRScanner with Network Camera

In today's age of digital transformation, QR codes are becoming increasingly popular as they make it easy to share information quickly and easily. QR codes can be scanned using a camera on a mobile device or a dedicated scanner. In this article, we will focus on developing a PHP QRScanner that can scan QR codes using a network camera.

Prerequisites

To follow along with this tutorial, you will need the following:

• PHP installed on your system.
• A network camera that supports RTSP streaming.
• A PHP web server such as XAMPP or WAMP.

Steps

Step 1: Install Required Packages

We will use the guzzlehttp/guzzle package to establish a connection with the network camera. Run the following command to install the package:

composer require guzzlehttp/guzzle

Step 2: Create the QRScanner Class

In this step, we will create a QRScanner class that will handle scanning QR codes. The class will contain a scanQrCode method that will take the URL of the network camera as a parameter and return the decoded QR code.

require 'vendor/autoload.php';

use GuzzleHttp\ClientInterface;
use GuzzleHttp\Exception\GuzzleException;
use GuzzleHttp\Client;

class QRScanner
{
    private $client;

    public function __construct(ClientInterface $client = null)
    {
        $this->client = $client ?: new Client();
    }

    public function scanQrCode($url)
    {
        // TODO: Implement scanning QR code using network camera
    }
}

Step 3: Scan QR Code

In this step, we will implement the scanQrCode method of the QRScanner class. We will use the guzzlehttp/guzzle package to make a request to the network camera and return the decoded QR code.

public function scanQrCode($url)
{
    try {
        $response = $this->client->request('GET', $url);

        $img = imagecreatefromstring($response->getBody()->getContents());
        $qrCode = false;

        if ($img !== false) {
            $scanner = new ZBarScanner();
            $qrCode = $scanner->scan($img);
        }

        return $qrCode;
    } catch (GuzzleException $e) {
        echo $e->getMessage();
    }
}

Step 4: Test the QRScanner

Create a new PHP file named index.php and add the following code:

require 'QRScanner.php';

$scanner = new QRScanner();
$qrCode = $scanner->scanQrCode('http://192.168.0.10:554/onvif/media_service/snapshot?channel=1&subtype=0');

if ($qrCode) {
    echo 'QR Code: ' . $qrCode->getData() . PHP_EOL;
} else {
    echo 'No QR Code found.' . PHP_EOL;
}

Run the PHP file in your web server and test the QRScanner by pointing the network camera to a QR code. The scanned QR code should be displayed on the web page.

Conclusion

In this tutorial, we learned how to develop a PHP QRScanner that can scan QR codes using a network camera. We used the guzzlehttp/guzzle package to establish a connection with the network camera and the ZBarScanner library to scan the QR code.