[[!getImage? &path=`/images/` &image=`email_hero.jpg` &options=`&w=540` ]]

getImage.php

<?php

$path = $modx->getOption('path', $scriptProperties, '');
$image = $modx->getOption('image', $scriptProperties, '');
$options = $modx->getOption('options', $scriptProperties, '');
$resizer = $modx->getOption('useResizer', $scriptProperties, 1);


$imagePath = $modx->runSnippet('pthumb', array(
   'input' => $path.$image,
   'options' => $options,
   'useResizer' => $resizer
));
if ($path.$image == $imagePath) {
    $modx->log(modX::LOG_LEVEL_ERROR, 'image not found!');
} else {
    $url = $modx->config['site_url'];
    $imageUrl = $url.$imagePath;
    $imageMime = image_type_to_mime_type(exif_imagetype($imageUrl));
    $fp = fopen($imageUrl, 'rb');
header('Content-Type: '.$imageMime);
header("Cache-Control: no-store, no-cache, must-revalidate, max-age=0");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");
    fpassthru($fp);
}
exit;