如何使用PHP裁剪圖片的指定區域

sudo apt-get install php-gd

function cropImage($sourcePath, $targetPath, $x, $y, $width, $height) {
    // 获取图片的类型
    $imageType = exif_imagetype($sourcePath);
    
    // 根据图片类型创建画布
    switch ($imageType) {
        case IMAGETYPE_JPEG:
            $sourceImage = imagecreatefromjpeg($sourcePath);
            break;
        case IMAGETYPE_PNG:
            $sourceImage = imagecreatefrompng($sourcePath);
            break;
        case IMAGETYPE_GIF:
            $sourceImage = imagecreatefromgif($sourcePath);
            break;
        default:
            return false;
    }
    
    // 创建裁剪后的画布
    $targetImage = imagecreatetruecolor($width, $height);
    
    // 裁剪图片
    imagecopy($targetImage, $sourceImage, 0, 0, $x, $y, $width, $height);
    
    // 保存裁剪后的图片
    imagejpeg($targetImage, $targetPath);
    
    // 释放资源
    imagedestroy($sourceImage);
    imagedestroy($targetImage);
    
    return true;
}

<form action="crop.php" method="post" enctype="multipart/form-data">
    <label for="image">选择要裁剪的图片：</label>
    <input type="file" name="image" id="image">
    <br>
    <label for="x">裁剪起点 x 坐标：</label>
    <input type="text" name="x" id="x">
    <br>
    <label for="y">裁剪起点 y 坐标：</label>
    <input type="text" name="y" id="y">
    <br>
    <label for="width">裁剪宽度：</label>
    <input type="text" name="width" id="width">
    <br>
    <label for="height">裁剪高度：</label>
    <input type="text" name="height" id="height">
    <br>
    <input type="submit" value="裁剪">
</form>

<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
    $sourcePath = $_FILES['image']['tmp_name'];
    $targetPath = 'path/to/save/cropped/image.jpg';
    $x = $_POST['x'];
    $y = $_POST['y'];
    $width = $_POST['width'];
    $height = $_POST['height'];
    
    if (cropImage($sourcePath, $targetPath, $x, $y, $width, $height)) {
        echo '图片裁剪成功！';
    } else {
        echo '图片裁剪失败！';
    }
}
?>