gistfile1.aw

<?php
/**
 * Limit Search to Video
 * @author Bill Erickson
 * @link http://www.billerickson.net/wordpress-search-post-type/
 *
 * @param string search form
 * @param string search text
 * @param string button text
 * @return string modified search form
 */
 function be_search_limit($form, $search_text, $button_text) {
 	if( !( is_post_type_archive( 'video' ) || is_singular( 'video' ) ) )
 		return $form;
 
	$onfocus = " onfocus=\"if (this.value == '$search_text') {this.value = '';}\"";
	$onblur = " onblur=\"if (this.value == '') {this.value = '$search_text';}\"";
	$video_form = '
		<form method="get" action="' . get_option('home') . '/" >
		<input type="text" value="'. $search_text .'" name="s"'. $onfocus . $onblur .' />
		<input type="hidden" name="post_type" value="video" />
		<input type="submit" value="'. $button_text .'" />
		</form>
	';
	return $video_form;
}
add_filter('genesis_search_form', 'be_search_limit', 10, 3);