nerrad

/**
* This could be extrapolated and used for tags or any other taxonomy really.
*/

add_action('init', 'category_cpt_rewrites');

function category_cpt_rewrites() {
    $custom_post_types = array('video', 'audio', 'photo', 'file'); //some example post types
    foreach ( $custom_post_types as $post_type ) {
        $rule = '^' . $post_type . '/category/(.+?)/?$';