echo "<img src=".$file." >" ;
does not display image, while $file points to the correct image location C:\wamp\www\formulae\public\images\13.png
part of code reads as follows
$file = LIBPATH.DS.'images'.DS.$id.'.png' ;
if(file_exists($file)){
echo $file."</br>";
echo "<img src='".$file."' >" ;
}
would help you