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


	var prepare_slider = function(){
		
		var x_pos = 0;
		var li_items_n = 0;	
		var li_col = $('slider_list').getElements('li');
	
		li_col.each(function(li, index){
			size = li.getSize();
			x_pos += size.x;
			li_items_n++;
			li.getElement('img').setStyle('cursor','pointer');
			li.getElement('img').addEvent('click', function(){
																	
																	image_source = li.getElement('img').get('src');
																	ext = getFileExtension(image_source);
																	
																	
																	$('gall_view').innerHTML = '<img src="'+ ext[1]+'_big.'+ext[2] +'" >';
															})
			
			
		})
		
		
	}