Simple images API PHP

simple-image-api.php

<?php
/*
  JSON list of all images files in current directory
 */
header("Access-Control-Allow-Origin: *");

$dir = ".";
$dh = opendir($dir);
$image_files = array();

while (($file = readdir($dh)) !== false) {
    // Exclude retina versions from listing
    if (preg_match("/[^@]*(?!.*@2x)\.(jpg|png|gif|jpeg)/A", $file)) {
        $image_files []= $_SERVER['SCRIPT_URI'].'/'.$file;
    }
}

// Return response as JSON
echo json_encode($image_files);

closedir($dh);
?>