Try this:
Code:
{assign var="bitpath" value="players/`$v.field_value`-byzWRkIQ.js"}
{assign var="bitexpires" value=$smarty.now+3600}
{assign var="bitexpires" value=$bitexpires/60}
{assign var="bitexpires" value=$bitexpires|round}
{assign var="bitexpires" value=$bitexpires*60}
{assign var="bitsig" value="`$bitpath`:`$bitexpires`:XQk1AIiCdNSBY57g5WlHpKcs"|md5}
<p>Watch this cool video:</p>
<script type='text/javascript' src='http://content.bitsontherun.com/{$bitpath}?exp={$bitexpires}&sig={$bitsig}'></script>