最后我得到了解决方案,这是代码:
<?php
$dbconn = @mysql_connect($mysql_server,$mysql_manager_id,$mysql_manager_pw) or exit("SERVER Unavailable");
@mysql_select_db($mysql_database,$dbconn) or exit("DB Unavailable");
$sql = "SELECT id, original_name, type, content FROM upload WHERE id=". $_GET["imgid"];
$result = @mysql_query($sql,$dbconn) or exit("QUERY FAILED!");
$fileID = @mysql_result($result,0,"id");
$contenttype = @mysql_result($result,0,"type");
$filename = @mysql_result($result,0,"original_name");
$image = @mysql_result($result,0,"content");
$fileXtension = pathinfo($filename, PATHINFO_EXTENSION);
$finalFileName = $fileID.".".$fileXtension;
// put the file on temporary folder
$filePutPath = "/your/temporary/folder/".$finalFileName;
// put the contents onto file system
file_put_contents($filePutPath, $image);
// get the watermark image
$stamp = imagecreatefrompng('../images/watermark.png');
switch($fileXtension)
{
case 'JPEG':
case 'JPG' :
case 'jpg' :
case 'jpeg':
$im = imagecreatefromjpeg($filePutPath);
break;
case 'gif' :
case 'GIF' :
$im = imagecreatefromgif($filePutPath);
break;
case 'png' :
case 'PNG' :
$im = imagecreatefromgif($filePutPath);
break;
default :
break;
}
list($width, $height) = getimagesize($filePutPath);
// set area for the watermark to be repeated
imagecreatetruecolor($width, $height);
// Set the tile (Combine the source image and the watermark image together)
imagesettile($im, $stamp);
// Make the watermark repeat the area
imagefilledrectangle($im, 0, 0, $width, $height, IMG_COLOR_TILED);
header("Content-type: $contenttype");
// free the memory
imagejpeg($im);
imagedestroy($im);
// delete the file on temporary folder
unlink($filePutPath);
mysql_close($dbconn);
?>