PHP function that decodes GoldMine's log timestamp values

php GM Decode

function Decode($strValueIn) {
	$intX = 0;
	$intY = 0;
	$Temp = "";
	$Mod = "";
	$intMod =0;
	$intTemp = 0;
	$ValueOut = "";
	$intY = 1;
	$strValueOut="";
	
	for ($intX = 1; $intX <= ((strlen($strValueIn)/2)/2); $intX++) {

		$strTemp="";
		$strMod="";
		
		if (($intX % 2) == 0) {
			$strMod = substr(substr($strValueIn, $intY-1, 4),0,2);
			$strTemp = substr(substr($strValueIn, $intY-1, 4),strlen(substr($strValueIn, $intY-1, 4))-(2));
	    } else {
			$strMod = substr(substr($strValueIn, $intY-1,4), strlen(substr($strValueIn, $intY-1, 4))-(2));
			$strTemp = substr(substr($strValueIn, $intY-1,4), 0, 2);
		}

		$intMod = hexdec($strMod);
		$intTemp = hexdec($strTemp);
		$intTemp = $intTemp-$intMod;
		$strValueOut = $strValueOut . chr($intTemp);
		$intY += 4;
	} 
	
	return $strValueOut;
}