Hi, to generate a resized image try this code:
<?php
if($upload->moveTo($path))
{
$name_of_miniature = "example_name123";
$img = new Phalcon\Image\Adapter\Gd($path);
$path_mini = "img/miniatures/".$name_of_miniature.".jpg";
//117 px width, 90 px height
$img->resize(117,90)->crop(117,90);
if($img->save($path_mini, 100))
{
// ok
}
else
{
// bad
}
}