Genesis custom context with filter and callback to append the custom attributes.

functions.php

<?php

add_filter( 'genesis_attr_movie', 'custom_add_movie_attr' );
/**
 * Callback for dynamic Genesis 'genesis_attr_$context' filter.
 * 
 * Add custom attributes for the custom filter.
 * 
 * @param array $attributes The element attributes
 * @return array $attributes The element attributes
 */
function custom_add_movie_attr( $attributes ){
        
        // add itemscope
        $attributes['itemscope'] = '';
        
        // add the Movie itemtype schema
        $attributes['itemtype'] = 'http://schema.org/Movie';
        
        // return the attributes
        return $attributes;
        
}

page.php

<?php

genesis_markup( array(
        'html5'   => '<div %s>',
        'xhtml'   => '<div>',
        'context' => 'movie'
) );