1. Go to this page and download the library: Download stereoflo/image-resize library. Choose the download type require.
2. Extract the ZIP file and open the index.php.
3. Add this code to the index.php.
<?php
require_once('vendor/autoload.php');
/* Start to develop here. Best regards https://php-download.com/ */
stereoflo / image-resize example snippets
$image = new \ImageResize\Image('pathToYouSourceImage');