PHP: substr

gistfile1

<?php

    $images = array(
      'logo.png',
      'background.jpg',
      'http://www.hardcoregamer.com/wp-content/uploads/2014/03/BAK_Sshot019.jpg'
      );

    foreach ($images as $image) {
      $src = (substr($image,0,4) == 'http') ? $image : "images/$image";
      echo $src . "<br />";
     }