I make no apologies for compatibility with other systems. This class needs PHP 5.1 + (I think) and GD version >= 2
Briefly, there are currently these methods...
<?php
$image->gradientFrame($colour, $colour, (int)$width, (bool)$maintainSize);
$image->applyTile($image, (int)$opacity);
$image->rotate((int)$degrees);
$image->watermark($image, (string)$posLeft, (string)$posTop, (int)$padding, (int)$opacity);
$image->adjustBrightness((int)$percent); // from -100 to 100
$image->gaussianBlur((int)$intensity);
$image->invert();
$image->setTransparency((int)$percent);
$image->adjustGamma((float)$from, (float)$to);
$image->convertToGray();
$image->resize((int)$width, (int)$height, (bool)$constrainProportions);
$image->undo(); // Undo Last action
$image->show(IMAGETYPE_PNG|IMAGETYPE_JPEG|IMAGETYPE_GIF, (int)$jpegQuality);
$image->save((string)$path, (int)$imgFormat, (int)$jpegQuality, (bool)$overwrite);
$image->setBackground((mixed)$colour);
?>