title: GroceryCRUD - how to set variables in a callback? (I upload a file, want to resize it 3 times and put all 3 in the db - how do i save that data)?
body: <p>I am using codeigniter + grocerycrud. I have a callback for image uploads.</p>
  
  <p>I upload one image in the form, but want to do this:</p>
  
  <p>copy it 3 times</p>
  
  <p>resize each one a certain size</p>
  
  <p>then save each one in the database.</p>
  
  <p>any ideas how to do this? The callback only seems to let me edit the image (and do things like that) - not change the varaiables of the submitted data so we can save the manipulated data.</p>
  
  <p>looking at their callback tutorial it looks like most call backs do something like this:</p>
  
  <pre><code>function callback_for_this_field($posted_data) {
  
  $posted_data = $posted_data .= "append me";
  
  return $posted_data;
  }
  </code></pre>
  
  <p>(ie returning the modified data)</p>
  
  <p>but the upload callback just returns true</p>