php减少上传图片大小

<?php
function compressImage($source, $destination, $quality) {
    $info = getimagesize($source);

    if ($info['mime'] == 'image/jpeg') {
        $image = imagecreatefromjpeg($source);
        imagejpeg($image, $destination, $quality);
    } elseif ($info['mime'] == 'image/png') {
        $image = imagecreatefrompng($source);
        imagepng($image, $destination, 9 - ($quality / 10));
    } elseif ($info['mime'] == 'image/gif') {
        $image = imagecreatefromgif($source);
        imagegif($image, $destination);
    }
    imagedestroy($image);
}

$source = 'path/to/source/image.jpg';
$destination = 'path/to/destination/image.jpg';
$quality = 75; // 质量范围为0-100

compressImage($source, $destination, $quality);
?>