Create wm.php and insert:
<?php
//we tell the server to treat this file as if it wore an image
header('Content-type: image/jpeg');
//image file path
$img = $_GET['src'];
//watermark position
$p = $_GET['p']; if(!$p) $p = 'br';
/*
p can be anything from the following list:
tl = top left
tc = top center
tr = top right
cl = center left
c = center of the image
cr = center right
bl = bottom left
bc = bottom center
br = bottom right
*/
//watermarked image quality
$q = $_GET['q'];
//if the quality field is missing or is not on the 0 to 100 scale then we set the quality to 93
if(!$q || $q<0 || $q>100) $q = '93';
$filetype = substr($img,strlen($img)-4,4);
$filetype = strtolower($filetype);
if($filetype == ".gif") $image = @imagecreatefromgif($img);
if($filetype == ".jpg") $image = @imagecreatefromjpeg($img);
if($filetype == ".png") $image = @imagecreatefrompng($img);
if (!$image) die();
//getting the image size for the original image
$img_w = imagesx($image);
$img_h = imagesy($image);
//if the filename has 150x150 in it's name then we don't apply the watermark
if (eregi("150x150", $img)) {
imagejpeg($image, null, $q); die();
} else {
$watermark = @imagecreatefrompng('bwmark.png');
}
/*
//if you want to use the watermark only on bigger images then use this instead of the condition above
if ($img_w < "150") {//if image width is less then 150 pixels imagejpeg($image, null, $q); die(); } else { $watermark = @imagecreatefrompng('bwmark.png'); } */ //getting the image size for the watermark $w_w = imagesx($watermark); $w_h = imagesy($watermark); if($p == "tl") { $dest_x = 0; $dest_y = 0; } elseif ($p == "tc") { $dest_x = ($img_w - $w_w)/2; $dest_y = 0; } elseif ($p == "tr") { $dest_x = $img_w - $w_w; $dest_y = 0; } elseif ($p == "cl") { $dest_x = 0; $dest_y = ($img_h - $w_h)/2; } elseif ($p == "c") { $dest_x = ($img_w - $w_w)/2; $dest_y = ($img_h - $w_h)/2; } elseif ($p == "cr") { $dest_x = $img_w - $w_w; $dest_y = ($img_h - $w_h)/2; } elseif ($p == "bl") { $dest_x = 0; $dest_y = $img_h - $w_h; } elseif ($p == "bc") { $dest_x = ($img_w - $w_w)/2; $dest_y = $img_h - $w_h; } elseif ($p == "br") { $dest_x = $img_w - $w_w; $dest_y = $img_h - $w_h; } imagecopy($image, $watermark, $dest_x, $dest_y, 0, 0, $w_w, $w_h); imagejpeg($image, null, $q); imagedestroy($image); imagedestroy($watermark); ?>
Create index.php and insert:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> </head> <body> <img src="wm.php?p=bl&q=100&src=INSERT-YOUR-IMAGE.jpg"> </body> </html>
source: http://dolcepixel.com/how-to-watermark-all-your-uploaded-images/