Superimpose Images with PHP

I am searching for a way to overlay an image on an existing image.

e.g:

I have found a great example over here: PNG overlay using one single Image element. but I have two problems with these.

First of all, I don't want the dimensions to be equal to each other. e.g (215*215 on 215*215). This is because my users would have the ability to choose where they want to put their image. (Top, left, bottom, top-right) so 8 directions.

The second problem is that in that example, only 2 images are allowed to overlay. 开发者_如何转开发My users (again) will have the ability to put multiple images on top of it.

I have a little knowledge of Javascript and PHP, so it would be great if you guys (and girls) could help me out.

Sincerely,

You can do this using GD library. There is function to "merge" images called imagecopymerge.

Here is a very simple example how to merge images:

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

$bg = imagecreatefromjpeg('background.jpg');
$img = imagecreatefromjpeg('image.jpg');

imagecopymerge($bg, $img, 0, 0, 0, 0, imagesx($bg), imagesy($bg), 75);

imagejpeg($bg, null, 100);
?>