/**
	 * Method return JSON array containing info about image.
	 * 
	 * @param gd - GD object used for retrieving info about image
	 * @param file 
	 * 
	 * @return string JSON array explained in manipulate method comment
	*/ 
	
	private function getImageInfoInJSON(GD $gd,$file) {
		return '{"fileName":"' . $file . '","width":' . $gd->getWidth() . ',"height":' . $gd->getHeight() . '}';
	}