function getFileExtension(filename)
{
 var ext = /(^.+)\.([^.]+)$/.exec(filename);
 return ext;
}


 var prepare_slider = function(){

 var x_pos = 0;
 var li_items_n = 0;
 var right_clicks = 0;
 var viewWindow = 3;
 var left_clicks = 0;

 var li_col = $("#slider_list li");

 li_col.each(function(index){
 //size = li.getSize();
 x_pos += $(this).width();

 li_items_n++;

 $(this, "img").css('cursor','pointer');



 })


 right_clicks = li_items_n - viewWindow;
 total_clicks = li_items_n - viewWindow;

 $('#slider_list').css('position','relative');
 $('#slider_list').css('left','0px');
 $('#slider_list').css('width', x_pos+'px');






 var is_playing = false;

 var completed = function() { is_playing = false; }

 $('#left_but').click( function(){


 cur_offset = $('#slider_list').position().left;




if (!is_playing) {

 if (left_clicks > 0) {is_playing = true; $('#slider_list').animate({'left': cur_offset + 171 + 'px'}, 700, "linear", completed); right_clicks++; left_clicks--;} else {is_playing = true; $('#slider_list').animate({'left': -171*total_clicks + 'px'}, 700, "linear", completed); right_clicks = 0; left_clicks = total_clicks;}
}
 });

 $('#right_but').click( function(){

 if (!is_playing) {

 cur_offset = $('#slider_list').position().left;

 if (right_clicks > 0) {is_playing = true; $('#slider_list').animate({'left': cur_offset - 171 + 'px'},700, "linear", completed ); right_clicks--; left_clicks++; } else { is_playing = true; $('#slider_list').animate({'left': 0 + 'px'},700, "linear", completed ); left_clicks = 0; right_clicks = total_clicks;}

 }
 });

 }