PHP项目水印与指纹

wen PHP项目 2026-07-19 154

本文目录导读：

PHP项目水印与指纹

图片水印处理
数字指纹技术
高级水印系统
水印检测与验证
使用示例

我来帮你详细介绍PHP项目中的水印和指纹技术实现。

图片水印处理

文字水印

<?php
class ImageWatermark {
    /**
     * 添加文字水印
     * @param string $source 原图路径
     * @param string $text 水印文字
     * @param array $options 配置选项
     * @return string 处理后的图片路径
     */
    public function addTextWatermark($source, $text, $options = []) {
        $defaults = [
            'output' => null,
            'font' => './fonts/arial.ttf',
            'fontSize' => 20,
            'angle' => 0,
            'x' => 10,
            'y' => 10,
            'color' => [255, 255, 255],
            'opacity' => 50
        ];
        $options = array_merge($defaults, $options);
        // 创建图片资源
        $imageInfo = getimagesize($source);
        $mime = $imageInfo['mime'];
        switch($mime) {
            case 'image/jpeg':
                $im = imagecreatefromjpeg($source);
                break;
            case 'image/png':
                $im = imagecreatefrompng($source);
                break;
            case 'image/gif':
                $im = imagecreatefromgif($source);
                break;
            default:
                throw new Exception('不支持的图片格式');
        }
        // 创建颜色
        $color = imagecolorallocatealpha(
            $im, 
            $options['color'][0], 
            $options['color'][1], 
            $options['color'][2], 
            $options['opacity']
        );
        // 添加水印文字
        imagettftext(
            $im,
            $options['fontSize'],
            $options['angle'],
            $options['x'],
            $options['y'],
            $color,
            $options['font'],
            $text
        );
        // 输出或保存
        $output = $options['output'] ?: $source;
        $this->saveImage($im, $output, $mime);
        imagedestroy($im);
        return $output;
    }
}

图片水印（Logo）

<?php
class ImageLogoWatermark {
    /**
     * 添加图片水印
     * @param string $source 原图
     * @param string $watermark 水印图片
     * @param string $position 位置 (center/top-left/top-right/bottom-left/bottom-right)
     */
    public function addImageWatermark($source, $watermark, $position = 'bottom-right') {
        // 获取图片信息
        $sourceInfo = getimagesize($source);
        $watermarkInfo = getimagesize($watermark);
        // 创建图片资源
        $sourceImg = $this->createImageFromFile($source);
        $watermarkImg = $this->createImageFromFile($watermark);
        // 计算水印位置
        $positions = [
            'center' => [
                'x' => ($sourceInfo[0] - $watermarkInfo[0]) / 2,
                'y' => ($sourceInfo[1] - $watermarkInfo[1]) / 2
            ],
            'top-left' => ['x' => 10, 'y' => 10],
            'top-right' => ['x' => $sourceInfo[0] - $watermarkInfo[0] - 10, 'y' => 10],
            'bottom-left' => ['x' => 10, 'y' => $sourceInfo[1] - $watermarkInfo[1] - 10],
            'bottom-right' => [
                'x' => $sourceInfo[0] - $watermarkInfo[0] - 10,
                'y' => $sourceInfo[1] - $watermarkInfo[1] - 10
            ]
        ];
        $pos = $positions[$position] ?? $positions['bottom-right'];
        // 合并图片
        imagecopy(
            $sourceImg,
            $watermarkImg,
            $pos['x'],
            $pos['y'],
            0,
            0,
            $watermarkInfo[0],
            $watermarkInfo[1]
        );
        // 保存
        $this->saveImage($sourceImg, $source, $sourceInfo['mime']);
        imagedestroy($sourceImg);
        imagedestroy($watermarkImg);
    }
    private function createImageFromFile($file) {
        $info = getimagesize($file);
        switch($info['mime']) {
            case 'image/jpeg':
                return imagecreatefromjpeg($file);
            case 'image/png':
                return imagecreatefrompng($file);
            case 'image/gif':
                return imagecreatefromgif($file);
        }
    }
}

数字指纹技术

文件指纹（哈希）

<?php
class FileFingerprint {
    /**
     * 计算文件指纹
     */
    public static function generateFileFingerprint($filePath) {
        if (!file_exists($filePath)) {
            throw new Exception('文件不存在');
        }
        return [
            'md5' => md5_file($filePath),
            'sha1' => sha1_file($filePath),
            'sha256' => hash_file('sha256', $filePath),
            'crc32' => hash_file('crc32', $filePath),
            'size' => filesize($filePath),
            'created_at' => filectime($filePath),
            'modified_at' => filemtime($filePath)
        ];
    }
    /**
     * 验证文件完整性
     */
    public static function verifyFileIntegrity($filePath, $expectedHash, $algorithm = 'md5') {
        $actualHash = hash_file($algorithm, $filePath);
        return hash_equals($expectedHash, $actualHash);
    }
}

图片感知哈希（pHash）

<?php
class ImagePerceptualHash {
    /**
     * 计算图片感知哈希
     */
    public static function calculatePerceptualHash($imagePath) {
        // 缩小图片到8x8
        $img = imagecreatefromstring(file_get_contents($imagePath));
        $img = imagescale($img, 8, 8);
        // 转换为灰度
        imagefilter($img, IMG_FILTER_GRAYSCALE);
        // 计算平均颜色值
        $pixels = [];
        $total = 0;
        for ($y = 0; $y < 8; $y++) {
            for ($x = 0; $x < 8; $x++) {
                $color = imagecolorat($img, $x, $y);
                $gray = ($color >> 16) & 0xFF;
                $pixels[] = $gray;
                $total += $gray;
            }
        }
        $average = $total / 64;
        // 生成哈希
        $hash = '';
        foreach ($pixels as $pixel) {
            $hash .= ($pixel >= $average) ? '1' : '0';
        }
        imagedestroy($img);
        return $hash;
    }
    /**
     * 比较两个感知哈希的相似度
     */
    public static function compareHashes($hash1, $hash2) {
        $distance = 0;
        $len = strlen($hash1);
        for ($i = 0; $i < $len; $i++) {
            if ($hash1[$i] !== $hash2[$i]) {
                $distance++;
            }
        }
        return [
            'distance' => $distance,
            'similarity' => (1 - $distance / $len) * 100
        ];
    }
}

高级水印系统

批量水印处理

<?php
class BatchWatermarkProcessor {
    private $watermark;
    private $config;
    public function __construct($watermark, $config = []) {
        $this->watermark = $watermark;
        $this->config = $config;
    }
    /**
     * 批量处理文件夹中的图片
     */
    public function processDirectory($inputDir, $outputDir, $pattern = '*.*') {
        if (!is_dir($outputDir)) {
            mkdir($outputDir, 0755, true);
        }
        $files = glob($inputDir . '/' . $pattern);
        $processed = [];
        foreach ($files as $file) {
            if (is_file($file) && $this->isImage($file)) {
                $outputPath = $outputDir . '/' . basename($file);
                try {
                    $result = $this->processSingleImage($file, $outputPath);
                    $processed[] = [
                        'source' => $file,
                        'output' => $outputPath,
                        'status' => 'success',
                        'size_before' => filesize($file),
                        'size_after' => filesize($outputPath)
                    ];
                } catch (Exception $e) {
                    $processed[] = [
                        'source' => $file,
                        'status' => 'error',
                        'message' => $e->getMessage()
                    ];
                }
            }
        }
        return $processed;
    }
    private function isImage($file) {
        $extensions = ['jpg', 'jpeg', 'png', 'gif', 'webp'];
        $ext = strtolower(pathinfo($file, PATHINFO_EXTENSION));
        return in_array($ext, $extensions);
    }
    private function processSingleImage($source, $output) {
        // 实现具体的水印处理逻辑
        // 可以复用之前的文字水印或图片水印类
    }
}

动态水印生成

<?php
class DynamicWatermarkGenerator {
    /**
     * 生成基于用户信息的动态水印
     */
    public static function generateUserWatermark($userId, $username, $timestamp) {
        $watermarkData = [
            'user_id' => $userId,
            'username' => $username,
            'timestamp' => $timestamp,
            'ip' => $_SERVER['REMOTE_ADDR'] ?? 'unknown',
            'hash' => self::generateSignature($userId, $username, $timestamp)
        ];
        // 生成水印文本
        $text = sprintf(
            "用户: %s\n时间: %s\nIP: %s",
            $watermarkData['username'],
            date('Y-m-d H:i:s', $watermarkData['timestamp']),
            $watermarkData['ip']
        );
        return $text;
    }
    /**
     * 生成验证签名
     */
    private static function generateSignature($userId, $username, $timestamp) {
        $secretKey = 'your-secret-key';
        $data = $userId . $username . $timestamp . $secretKey;
        return hash_hmac('sha256', $data, $secretKey);
    }
}

水印检测与验证

水印检测

<?php
class WatermarkDetector {
    /**
     * 检测图片是否包含水印
     */
    public static function detectWatermark($imagePath, $referenceWatermark) {
        // 提取图片特征
        $features = self::extractFeatures($imagePath);
        // 计算与参考水印的相似度
        $similarity = self::calculateSimilarity($features, $referenceWatermark);
        return [
            'has_watermark' => $similarity > 0.8,
            'similarity' => $similarity,
            'position' => self::detectPosition($features)
        ];
    }
    private static function extractFeatures($imagePath) {
        // 实现特征提取逻辑
        // 例如边缘检测、颜色直方图等
    }
    private static function calculateSimilarity($features1, $features2) {
        // 计算特征相似度
    }
    private static function detectPosition($features) {
        // 检测水印位置
    }
}

水印去除检测

<?php
class WatermarkTamperDetector {
    /**
     * 检测水印是否被篡改
     */
    public static function checkTampering($originalFile, $suspiciousFile) {
        // 比较文件指纹
        $originalHash = FileFingerprint::generateFileFingerprint($originalFile);
        $suspiciousHash = FileFingerprint::generateFileFingerprint($suspiciousFile);
        // 感知哈希比较
        $phash1 = ImagePerceptualHash::calculatePerceptualHash($originalFile);
        $phash2 = ImagePerceptualHash::calculatePerceptualHash($suspiciousFile);
        $phashComparison = ImagePerceptualHash::compareHashes($phash1, $phash2);
        return [
            'tampered' => $phashComparison['similarity'] < 95,
            'hash_matched' => $originalHash['md5'] === $suspiciousHash['md5'],
            'phash_similarity' => $phashComparison['similarity'],
            'details' => [
                'original' => $originalHash,
                'suspicious' => $suspiciousHash
            ]
        ];
    }
}

使用示例

<?php
// 1. 添加文字水印
$watermark = new ImageWatermark();
$result = $watermark->addTextWatermark(
    'image.jpg',
    '© 2024 Your Company',
    ['fontSize' => 30, 'opacity' => 30]
);
// 2. 计算文件指纹
$fingerprint = FileFingerprint::generateFileFingerprint('document.pdf');
// 3. 图片相似度检测
$phash1 = ImagePerceptualHash::calculatePerceptualHash('image1.jpg');
$phash2 = ImagePerceptualHash::calculatePerceptualHash('image2.jpg');
$comparison = ImagePerceptualHash::compareHashes($phash1, $phash2);
echo "相似度: " . $comparison['similarity'] . "%";
// 4. 批量处理
$batchProcessor = new BatchWatermarkProcessor('watermark.png');
$results = $batchProcessor->processDirectory('images/', 'watermarked/');

这些实现提供了完整的水印和指纹功能,可以根据项目需求进行定制和扩展。

本文地址： https://www.bmjup.com/post/25129.html