custom excerpt with filters

function improved_trim_excerpt($text) {

	global $post;

        if ( '' == $text ) {

                $text = get_the_content('');

                $text = apply_filters('the_content', $text);

                $text = str_replace('\]\]\>', ']]>', $text);

		$text = preg_replace('@<script[^>]*?>.*?</script>@si', '', $text);

		$text = preg_replace('@<script[^>]*?>.*?</script>@si', '', $text);

                $text = strip_tags($text, '<p>, <strong>, <a>, <br>');

                //$excerpt_length = 55;
		//re-introduce the possibility to change excerpt length with filter
		$excerpt_length = apply_filters('excerpt_length', 55);

		//re-introduce the possibility to use excerpt more filter
		$excerpt_more = apply_filters('excerpt_more', ' ' . '[...]');

                $words = explode(' ', $text, $excerpt_length + 1);

                if (count($words)> $excerpt_length) {

                        array_pop($words);

                        array_push($words, $excerpt_more); //edit

                        $text = implode(' ', $words);

                }

        }

        return $text;

}