How can I find the colour of a pixel of an image?
You must pass as parameters the image resource, and the x and y co-ordinates you want to find the color of, for instance:
$rgb = imagecolorat($im, 5, 10);
Will get a reference to the colour used at 5,10 (X,Y) on the image.
Depending on the version of the GD library you are using and the type of image, you may experience different return values, for more information take a look at:
http://uk3.php.net/manual/en/function.imagecolorat.php
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