Drupal: quickly generate an image file

gistfile1.php

<?php
  
$response = drupal_http_request('http://placekitten.com/g/' . $width . '/' . $height);
if ($response->code !== 200) {
  // If cats are sleeping, take another image generator
  $response = drupal_http_request('http://lorempixel.com/g/' . $width . '/' . $height);
}
$destination = 'public://miaou' . $width . 'x' . $height . '.png';
$file = file_save_data($response->data, $destination, FILE_EXISTS_REPLACE);