working with phpthumbof in modx to get at the raw file contents and output it directly.

modx pThumb raw data.php

<?php

// after I figured this out I realised I could just use mun.ee
// you probably should too!

if (!$modx) die();
  $debug = 0 || $_GET['debug'];
  if ($debug) require_once($modx->config['base_path'] . 'assets/php/kint-0.9/Kint.class.php');

  $options = array(
    'id' => 0,
    'defaultImages' => array(50,51,52,53,54,55,56,57),
    'width' => 900,
    'height' => 556,
    'blur' => 0, //set to '0' for no blur
    'clrSat' => 0, //set to '0' for no color
    'clrHex' => 'FFFFFF'
    );
  
  $options = array_merge($options, $_GET);

  if (!$options['id']) {
    print("no id");
    die();
  }
  
  //get specified image or choose a default
  $resource = $modx->getObject('modResource', $options['id']);
  $src = $resource->getTVValue('coverImage');
  
  if (!$src) {
    $defaultImage = $options['id'] % count($options['defaultImages']);
    $defaultImage = $options['defaultImages'][$defaultImage];
    $defaultImage = $modx->getObject('modResource', $defaultImage);
    $src = $defaultImage->getSourceFile();
  }

  //assemble phpthumbof options
  $phpThumbOpts = '';
  $phpThumbOpts .= '&zc=1&aoe=1';
  $phpThumbOpts .= '&w=' . $options['width'];
  $phpThumbOpts .= '&h=' . $options['height'];
  if ($options['blur']) $phpThumbOpts .= '&fltr[]=blur|' . $options['blur'];
  if ($options['clrSat']) $phpThumbOpts .= '&fltr[]=clr|' . $options['clrSat'] . '|' . $options['clrHex'];

  //run phpthumbof
  $args = array(
    'input' => $src,
    'options' => $phpThumbOpts
    );
  $src = $modx->runSnippet('phpThumbOf', $args);

  //translate path
  $src = preg_replace("/(.*assets\/)/", "", $src);
  $src = $modx->config['assets_path'] . $src;

  //debug
  if ($debug) {
    d($options);
    d(array($src, $args));
    die();
  }
  //output
  $im = imagecreatefromjpeg($src);
  header('Content-Type: image/jpeg');
  imagejpeg($im);
  die();