PHP怎么实现文件批量水印 图片批量加水印技巧

<?php

function addWatermarkToImages($imageDir, $watermarkPath, $outputDir) {
    $files = glob($imageDir . '/*.{jpg,jpeg,png,gif}', GLOB_BRACE); // 匹配jpg, jpeg, png, gif格式的图片

    if (!$files) {
        echo "No images found in directory: " . $imageDir . "\n";
        return;
    }

    $watermark = imagecreatefrompng($watermarkPath); // 假设水印是PNG格式
    if (!$watermark) {
        echo "Failed to load watermark image: " . $watermarkPath . "\n";
        return;
    }

    $watermarkWidth = imagesx($watermark);
    $watermarkHeight = imagesy($watermark);

    foreach ($files as $imagePath) {
        $imageInfo = getimagesize($imagePath);
        $imageType = $imageInfo[2];

        switch ($imageType) {
            case IMAGETYPE_JPEG:
                $image = imagecreatefromjpeg($imagePath);
                break;
            case IMAGETYPE_PNG:
                $image = imagecreatefrompng($imagePath);
                break;
            case IMAGETYPE_GIF:
                $image = imagecreatefromgif($imagePath);
                break;
            default:
                echo "Unsupported image type: " . $imagePath . "\n";
                continue 2; // 跳过本次循环
        }

        if (!$image) {
            echo "Failed to load image: " . $imagePath . "\n";
            continue;
        }

        $imageWidth = imagesx($image);
        $imageHeight = imagesy($image);

        // 计算水印位置 (右下角)
        $destX = $imageWidth - $watermarkWidth - 10; // 距离右边10像素
        $destY = $imageHeight - $watermarkHeight - 10; // 距离底部10像素

        imagecopy(
            $image,       // 目标图像
            $watermark,   // 水印图像
            $destX,       // 目标X坐标
            $destY,       // 目标Y坐标
            0,           // 水印X坐标
            0,           // 水印Y坐标
            $watermarkWidth,  // 水印宽度
            $watermarkHeight  // 水印高度
        );

        // 保存图像
        $newImagePath = $outputDir . '/' . basename($imagePath); // 输出到新的目录
        switch ($imageType) {
            case IMAGETYPE_JPEG:
                imagejpeg($image, $newImagePath, 90); // 质量90
                break;
            case IMAGETYPE_PNG:
                imagepng($image, $newImagePath);
                break;
            case IMAGETYPE_GIF:
                imagegif($image, $newImagePath);
                break;
        }

        imagedestroy($image);
        echo "Watermark added to: " . $imagePath . " and saved as " . $newImagePath . "\n";
    }

    imagedestroy($watermark);
}

// 使用示例
$imageDir = 'images'; // 图片所在目录
$watermarkPath = 'watermark.png'; // 水印图片路径
$outputDir = 'watermarked_images'; // 输出目录

// 确保输出目录存在
if (!is_dir($outputDir)) {
    mkdir($outputDir, 0777, true); // 创建目录，权限777，递归创建
}

addWatermarkToImages($imageDir, $watermarkPath, $outputDir);

?>

<?php

function addTransparentWatermark($imagePath, $watermarkPath, $outputDir, $opacity = 50) {
    $image = imagecreatefromjpeg($imagePath); // 假设是JPEG图片
    $watermark = imagecreatefrompng($watermarkPath);

    $imageWidth = imagesx($image);
    $imageHeight = imagesy($image);
    $watermarkWidth = imagesx($watermark);
    $watermarkHeight = imagesy($watermark);

    // 计算水印位置 (右下角)
    $destX = $imageWidth - $watermarkWidth - 10;
    $destY = $imageHeight - $watermarkHeight - 10;

    imagecopymerge(
        $image,
        $watermark,
        $destX,
        $destY,
        0,
        0,
        $watermarkWidth,
        $watermarkHeight,
        $opacity // 透明度
    );

    $newImagePath = $outputDir . '/' . basename($imagePath);
    imagejpeg($image, $newImagePath, 90);

    imagedestroy($image);
    imagedestroy($watermark);
}

// 使用示例
$imagePath = 'image.jpg';
$watermarkPath = 'watermark.png';
$outputDir = 'watermarked_images';
$opacity = 50; // 设置透明度为50%

addTransparentWatermark($imagePath, $watermarkPath, $outputDir, $opacity);

?>