为图片添加文字水印

<?php
$filename="des_big.jpg";
$fileInfo=getimagesize($filename);
//echo $fileInfo;  echo "<br>";
$mime=$fileInfo[‘mime‘]; 
//echo $mime; echo "<br>";
$createFun=str_replace("/","createfrom",$mime);
//echo $createFun; echo "<br>";
$outFun=str_replace("/",null,$mime);
$image=$createFun($filename);
//echo $image; echo "<br>";
$color=imagecolorallocatealpha($image,255,0,0,50);
$fontfile="../fonts/h.ttf";
$text="imooc.com";
imagettftext($image,14,0,0,14,$color,$fontfile,$text);
//header("content-type:".$mime);
$outFun($image,$filename);
imagedestroy($image);
echo "<img src=‘$filename‘>";
?>