how to have video thumb in the river

hello ,

i'm using "Video browser plugin"  version 1 and i would like to knowhow i can add

video thumbnail to the river page , it will be much more nice than that 

if anyone have an idea :)

here  is the code that create the river item 



$performed_by = get_entity($vars['item']->subject_guid); // $statement->getSubject();

$object = get_entity($vars['item']->object_guid);

$url = $object->getURL();

$url = "<a href=\"{$performed_by->getURL()}\">{$performed_by->name}</a>";

$string = sprintf(elgg_echo("video:river:created"),$url) . " ";

$string .= "<a href=\"" . $object->getURL() . "\">" . elgg_echo("video:river:item") . "</a>";


echo $string;


and here is the code that show the video thumb on the custom index 





$title2 = elgg_view_title(elgg_echo("New Videos"));

$body2 .= list_entities('object', 'video', 0, 3, false); 

echo $title2 . $body2;