How to use PHP to implement face recognition and identity authentication functions

How to use PHP to implement face recognition and identity authentication functions

Face recognition technology, as a biometric identification technology, has been widely used in recent years. It can extract and compare features through face images captured by cameras to achieve functions such as identity authentication. In this article, we will introduce how to use PHP to implement face recognition and identity authentication functions, and give code examples.

1. Preparation
First, we need a library that can perform face recognition. In PHP, we can use OpenCV extension to implement face recognition. Therefore, you first need to ensure that the OpenCV extension is installed on the server.

2. Collect face samples
Before performing face recognition, we need to collect a certain number of face samples as a training set. Collect pictures through the camera and save them in a folder. Each image should contain a face and can be saved by marking the face area.

// 收集人脸样本
function collectFaceSamples($userId)
{
    $stream = file_get_contents('php://input');
    if (!is_dir('faces/' . $userId)) {
        mkdir('faces/' . $userId);
    }
    file_put_contents('faces/' . $userId . '/' . uniqid() . '.jpeg', $stream);
}

3. Training model
After collecting face samples, we need to generate a face recognition model through training. Through training, the model can learn the characteristics of the face to facilitate subsequent recognition.

// 训练人脸识别模型
function trainModel()
{
    $pathToImages = 'faces';
    $pathToModel = 'model.xml';
    
    $images = [];
    $labels = [];
    
    $folders = scandir($pathToImages);
    foreach ($folders as $folder) {
        if ($folder != '.' && $folder != '..') {
            $files = scandir($pathToImages . '/' . $folder);
            foreach ($files as $file) {
                if ($file != '.' && $file != '..') {
                    $images[] = $pathToImages . '/' . $folder . '/' . $file;
                    $labels[] = $folder;
                }
            }
        }
    }
    
    $faceRecognizer = OpenCVcreateLBPHFaceRecognizer();
    $faceRecognizer->train($images, $labels);
    $faceRecognizer->save($pathToModel);
}

4. Face recognition
After the training model is completed, we can use the model for face recognition. Features are extracted from the face image captured by the camera and compared with the trained model to determine whether it belongs to a known user. If it is a known user, corresponding identity authentication can be performed.

// 人脸识别和身份认证
function recognizeAndAuthenticate()
{
    $pathToModel = 'model.xml';
    
    $stream = file_get_contents('php://input');
    $tempImage = 'temp.jpeg';
    file_put_contents($tempImage, $stream);
    
    $faceRecognizer = OpenCVcreateLBPHFaceRecognizer();
    $faceRecognizer->load($pathToModel);
    
    $image = OpenCVimread($tempImage);
    $grayImage = OpenCVcvtColor($image, OpenCVCOLOR_BGR2GRAY);
    
    $label = $faceRecognizer->predict($grayImage);
    
    // 判断是否属于已知用户
    if ($label == 'userId') {
        // 身份认证通过
        echo '认证通过';
    } else {
        // 身份认证失败
        echo '认证失败';
    }
    
    unlink($tempImage);
}

5. Call the face recognition and identity authentication functions
In actual applications, we can perform face recognition and identity authentication by calling the above functions. For example, an API interface can be used to process the image stream passed by the client and return the authentication result.

// API 接口
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    if ($_GET['action'] === 'collect') {
        // 收集人脸样本
        collectFaceSamples($_GET['userId']);
    } else if ($_GET['action'] === 'train') {
        // 训练模型
        trainModel();
    } else if ($_GET['action'] === 'recognizeAndAuthenticate') {
        // 人脸识别和身份认证
        recognizeAndAuthenticate();
    }
}

Through the above steps, we have successfully implemented face recognition and identity authentication functions using PHP. Using this function, we can apply it in various scenarios, such as access control systems, identity verification, etc.

At the same time, it should be noted that facial recognition technology still has some limitations and safety hazards, such as the inability to recognize facial wrinkles and wearing masks. Therefore, in practical applications, we need to comprehensively consider various factors and combine with other security measures to ensure the reliability and security of the system.

The above is the detailed content of How to use PHP to implement face recognition and identity authentication functions. For more information, please follow other related articles on the PHP Chinese website!