How to customize widget in PHP?

On step 4 of the  php tutorial I have:

<?php echo $api->widget->getScriptTag(); ?>
<form method="POST" action="upload.php">
   <?php echo $api->widget->getInputTag('qs-file'); ?>
   <input type="submit" value="Save!">

My question is how can i manipulate the getScriptTag(); to customize my widget.
i.e. only images, only one upload, crop

There is the second argument of getInputTag method. You can pass additional attributes.

<?php echo $api->widget->getInputTag('qs-file', array(
    "data-crop" => "4:3",
    "data-images-only" => "true",
)); ?>