PHP tool to convert the KML / RGB colors

function rgbToKml($color, $aa="ff"){
$rr = substr($color, 0, 2);
$gg = substr($color, 2, 2);
$bb = substr($color, 4, 2);
return $aa.$bb.$gg.$rr;
}
function kmlToRgb($color){
$rr = substr($color, 6, 2);
$gg = substr($color, 4, 2);
$bb = substr($color, 2, 2);
return $rr.$gg.$bb;
}