PHP+mysql，数据库中存取JPG、GIF文件，显示图象？？？？请帮忙。。谢谢！

<?php
//$contents就是从数据库读出的字符串//-----------读取
$filename = "F:/mm/M23406.jpg";
$fd = fopen ($filename, "r");
$contents = fread ($fd, filesize ($filename));
fclose ($fd);
//将$contents存入数据库中即可
//----------输出
//从数据库读出数据赋给$contents
$filename = "aaa1.jpg";
$fd = fopen ($filename, "w");
fwrite($fd,$contents);
fclose ($fd);?>