unable to add water mark to image

[chaitu11]

<?php
header('Content-type: image/jpeg');

$source = 'a.jpg';
$watermark = imagecreatefrompng('logo.png');
$watermark_width = imagesx($watermark);
$watermark_height = imagesy($watermark);
$image = imagecreatetruecolor($watermark_width,$watermark_height);
$image = imagecreatefromjpeg($source);
$image_size = getimagesize($source);
$x = $image_size[0] - $watermark_width - 10;
$y = $image_size[1] - $watermark_height - 10;
imagecopymerge($image, $watermark, $x, $y, 0, 0, $watermark_width, $watermark_height, 20);
imagejpeg($image);

?>

[cilla]

Just use this:

<?php
// Load the stamp and the photo to apply the watermark to
$stamp = imagecreatefrompng('stamp.png');
$im = imagecreatefromjpeg('photo.jpeg');

// Set the margins for the stamp and get the height/width of the stamp image
$marge_right = 10;
$marge_bottom = 10;
$sx = imagesx($stamp);
$sy = imagesy($stamp);

// Copy the stamp image onto our photo using the margin offsets and the photo 
// width to calculate positioning of the stamp. 
imagecopy($im, $stamp, imagesx($im) - $sx - $marge_right, imagesy($im) - $sy - $marge_bottom, 0, 0, imagesx($stamp), imagesy($stamp));

// Output and free memory
header('Content-type: image/png');
imagepng($im);
imagedestroy($im);
?>

src:PHP Manual

[cilla]

& customize as needed to get desired size and positioning...