<?php
declare(strict_types=1);

$image = imagecreate(2, 2);
$base = imagecolorallocate($image, 0, 0, 0);
$old = imagecolorallocate($image, 255, 0, 0);
imagesetpixel($image, 1, 1, $old);
imagesetpixel($image, 1, 1, $base);
var_dump(imagecolordeallocate($image, $old));
