title: Add 'Watermark' to images with php
body: <p>I have a website where users may upload images...</p>
  
  <p>I need to add my logo (watermark) to the images once they are uploaded.</p>
  
  <p>How can I do so?</p>
  
  <p>And it is important that the watermark is in a corner where it will be visible, for example I have seen websites which generates a watermark on the fly, and puts the mark wherever the background of the main image is "the same color" so the watermark sticks out if you know what I mean.</p>
  
  <p>Anybody have a good tutorial or article about this?
  Or know of any function in php which I would need to find the position of the watermark?</p>