$(document).ready(function(){ 
        $("#gallery_mini").find("a").eq(0).nextAll().fadeOut(800, function(){});
        setTimeout(function(){ showEffect(0) }, 4000);
});

function showEffect(id){
       var num_images = $("#gallery_mini img").length;
       
       var next_id = (id+1)%num_images;
  
       $("#gallery_mini").find("a").eq(id).fadeOut(800, function(){
        $("#gallery_mini").find("a").eq(next_id).fadeIn(800,  
              function(){  setTimeout(function(){ showEffect(next_id) }, 4000)
        })
       });
}