how to implement lightbox

Hi,
today I tried to include lightbox to the image display. Did someone made this?

I tried to modify the "node_kaltura_entry.module" . This is not completely the right way.. could some give me a hint? Where would you put the lightbox code.. what about the hook_view funktion?

...
function theme_node_kaltura_entry_entryId($node, $teaser) {
  if ($teaser && variable_get('kaltura_display_entry_video_teaser_with_player', 0) == 0) return '';
  if ($node->kaltura_media_type == 2) {
    $width = variable_get('kaltura_image_entry_width', '410');
    $height = variable_get('kaltura_image_entry_height', '364');
    
 /*  CUSTOM */
 
    return '<div class="lightbox_thumbnail">
              <a class="lightbox-processed"  href="'. $node->kaltura_thumbnail_url .'/width/'. $width .'/height/'. $height .'/type/1/quality/100"  rel="lightbox" title="my caption" >';
 }

function theme_node_kaltura_entry_thumbnail_url($node, $teaser, $nosize = FALSE, $size = array()) {
.....
  if ($node->link_thumb || $teaser)
    return '<div class="kaltura_thumb"><a href="'. url('node/'. $node->nid) .'"><img src="'. $node->kaltura_thumbnail_url . $size_str .'" '. $extra .' /></a></div>';
  else
    return '<img src="'. $node->kaltura_thumbnail_url . $size_str .'" '. $extra .' /></a>
            </div>';
}