function update_rucksack_movie(step,layer) {
 step++;
 if(step >= rucksack_movie_keys.length){
  step = 0;
 }
 other_layer = layer;
 if(layer == 1) {
  layer = 2;
 } else {
  layer = 1;
 }
 document.getElementById("rucksack_movie_image_" + other_layer).style.background = "url(" + rucksack_movie_image_path + rucksack_movie_keys[step] + ".jpg) no-repeat";
 document.getElementById("rucksack_movie_image_" + other_layer).href = rucksack_movie_link_path + "product_info.php?products_id=" + rucksack_movie_keys[step] + rucksack_movie_oscsid;
 document.getElementById("rucksack_movie_image_" + layer).style.display = "block";
 jQuery("#rucksack_movie_image_" + layer).fadeTo('slow',1);
 window.setTimeout("fade_out_rucksack_movie(" + step + "," + layer + ")", 2000);
}

function fade_out_rucksack_movie(step,layer) {
 jQuery("#rucksack_movie_image_" + layer).fadeTo('slow',0, function() {
  document.getElementById("rucksack_movie_image_" + layer).style.display = "none";
  update_rucksack_movie(step,layer);
 });
}

function start_rucksack_movie(step) {
 document.getElementById("rucksack_movie_image_1").style.background = "url(" + rucksack_movie_image_path + rucksack_movie_keys[step] + ".jpg) no-repeat";
 document.getElementById("rucksack_movie_image_1").href = rucksack_movie_link_path + "product_info.php?products_id=" + rucksack_movie_keys[step] + rucksack_movie_oscsid;
 jQuery("#rucksack_movie_image_1").css({opacity: 0});
 jQuery("#rucksack_movie_image_2").css({opacity: 0});
 window.setTimeout("update_rucksack_movie(" + step + ",2)", 500);
}