<?php
class StillsPage extends Page {
    private static $db = array(
        'TrailerVideoURL' => 'Text',
    );

    private static $has_many = array(
        'Stills' => 'Image'
    );

    function getCMSFields() {

        $fields = parent::getCMSFields();

        $fields->addFieldToTab(
            'Root.UploadStills',
            $uploadField = new UploadField(
                $name = 'Stills',
                $title = 'Upload one or more images (max 1000 in total)'
            )
        );
        $uploadField->setAllowedMaxFileNumber(1000);

        return $fields;
    }
}

class StillsPage_Controller extends Page_Controller {
}

class StillsPageImageExtension extends DataExtension {
    private static $belongs_one_many = array('Stills' => 'StillsPage');
}

Image::add_extension('StillsPageImageExtension');