php上传图片自动裁剪

<?php
function resizeAndCrop($imagePath, $targetWidth, $targetHeight) {
    // 获取原始图片尺寸
    list($originalWidth, $originalHeight) = getimagesize($imagePath);

    // 创建目标图片资源
    $targetImage = imagecreatetruecolor($targetWidth, $targetHeight);

    // 计算裁剪区域
    $x = ($originalWidth - $targetWidth) / 2;
    $y = ($originalHeight - $targetHeight) / 2;

    // 根据图片类型创建原始图片资源
    $imageType = exif_imagetype($imagePath);
    switch ($imageType) {
        case IMAGETYPE_JPEG:
            $sourceImage = imagecreatefromjpeg($imagePath);
            break;
        case IMAGETYPE_PNG:
            $sourceImage = imagecreatefrompng($imagePath);
            break;
        case IMAGETYPE_GIF:
            $sourceImage = imagecreatefromgif($imagePath);
            break;
        default:
            return false;
    }

    // 裁剪并调整图片大小
    imagecopyresampled($targetImage, $sourceImage, 0, 0, $x, $y, $targetWidth, $targetHeight, $targetWidth, $targetHeight);

    // 保存处理后的图片
    imagejpeg($targetImage, 'resized_' . basename($imagePath));

    // 释放资源
    imagedestroy($sourceImage);
    imagedestroy($targetImage);

    return true;
}

// 使用示例
$imagePath = 'path/to/your/image.jpg';
$targetWidth = 300;
$targetHeight = 200;
resizeAndCrop($imagePath, $width, $height);
?>