if( ! function_exists( 'videotube_filter_the_archive_title' ) ){
    /**
     * Filter the archive title.
     * @param string $archive_title
     */
    function videotube_filter_the_archive_title( $archive_title ) {

        if( is_tax( 'categories' ) || is_tax( 'video_tag' ) ){
            $archive_title  =   single_term_title( '', false );
        }

        return $archive_title;
    }
    add_filter( 'get_the_archive_title' , 'videotube_filter_the_archive_title', 10, 1 );
}