var step = -1;
var currentImage = 2;
var countImage = 6;
var thickImage = 1;

function Initialization(Sender) {

  if( currentImage > countImage )
    currentImage = 0;

  var Obj = $('collage-image-two');
  Obj.className = "collage-" + currentImage;

  var nextImage = currentImage + 1;

  if( currentImage == countImage )
    nextImage = 0;

  var Obj = $('collage-image-one');
  Obj.className = "collage-" + (nextImage);

  currentImage = nextImage;

  Executer = new PeriodicalExecuter(showPresentation, 0.1, Sender);
}

function showPresentation(Executer) {

  // если это не стопкадр, то делаем действие  
  if( thickImage
      && thickImage < 50 ) {
    thickImage++;
    return;
  }

  thickImage = 0;

  var Obj = $('collage-image-two');

  Obj.setOpacity(Obj.getStyle('opacity')+(0.1 * step));

  if( Obj.getStyle('opacity') <= 0
      || Obj.getStyle('opacity') >= 1 ) {

    if( step > 0 )
      step = -1;
    else
      step = 1;

    thickImage = 1;

    if( currentImage >= countImage-1 )
      currentImage = 0;
    else
      currentImage++;

    if( step < 0 )
      var Obj = $('collage-image-one');

    Obj.className = "collage-" + currentImage;
  }
}