Need a little help with this JS script

I have this script that shows a picture slide show from a database...

      <script language="javascript">
		var imgArray=new Array({$num_pictures});
		var switchImage={$set_slideShow_sec};
		var switchImageCountFrom={$set_slideShow_count_from};
		{foreach item=image from=$image_list}
			imgArray[{$image.nr}]="{$image.file}";
		{/foreach}
		</script>

Code (markup):

However it lacks controllers...you know "<< prev | next >>".

And I have no idea as I'm a noob to JS...

Hmm...This thing uses Smarty Engine so I don't know what the variables are set to...I can look if it's needed.