Reading pixels of images

[moon 111]

How could I open and read the pixel of an image? Could I use a regular function like you would use with a .txt file? If so what values am I looking for?

[Orio]

<?php

$x = 10;
$y = 8;
$image = imagecreatefromjpeg("image.jpg"); //or imagecreatefromgif(), imagecreatefrompng(), ...
$thiscol = imagecolorat($image, $x, $y);
$rgb = imagecolorsforindex($image, $thiscol);

echo "At pixel {$x},{$y} the color is RGB = {$rgb['red']},{$rgb['green']},{$rgb['blue']}";

?>

 

 

Orio.