function PhotoSlider(){
			
			this.init = function(p_eltId, p_sliddingEltId, p_nbPictures, p_pictureHeight, p_nbSecs){
				PhotoSlider.instancesList[p_eltId] = this;
				this.eltId = p_eltId;
				this.sliddingEltId = p_sliddingEltId;
				this.nbPictures = p_nbPictures;
				this.pictureHeight = p_pictureHeight;
				this.nbSecs = p_nbSecs;
				this.currentYOffset = 0;
				this.interval = null;
				this.isFreezed = true;
				
				this.mainElt = document.getElementById(p_eltId);
				this.sliddingElt = document.getElementById(p_sliddingEltId);
				if(window.addEventListener){
					this.mainElt.addEventListener('click',function(){PhotoSlider.findInstance(p_eltId).goOneUp()},false);
					this.mainElt.addEventListener('dblclick',function(){PhotoSlider.findInstance(p_eltId).stopSlide()},false);
					this.mainElt.addEventListener('mouseover',function(){PhotoSlider.findInstance(p_eltId).pauseSlide()},false);
					this.mainElt.addEventListener('mouseout',function(){PhotoSlider.findInstance(p_eltId).resumeSlide()},false);
				}else{
					this.mainElt.attachEvent('onclick',function(){PhotoSlider.findInstance(p_eltId).goOneUp()});
					this.mainElt.attachEvent('ondblclick',function(){PhotoSlider.findInstance(p_eltId).stopSlide()});
					this.mainElt.attachEvent('onmouseover',function(){PhotoSlider.findInstance(p_eltId).pauseSlide()});
					this.mainElt.attachEvent('onmouseout',function(){PhotoSlider.findInstance(p_eltId).resumeSlide()});
				}
				this.startSlide();

			}
			this.toogleSlide = function(){if(this.isFreezed==true){this.resumeSlide()}else{this.pauseSlide()}}
			this.pauseSlide = function(){this.isFreezed = true; this.mainElt.className='freezed';}
			this.resumeSlide = function(){this.isFreezed = false; this.mainElt.className='';}
			this.stopSlide = function(){if(this.interval!=null){clearInterval(this.interval);}}
			this.startSlide = function(){
				if(this.nbSecs>0){
					this.interval = setInterval("PhotoSlider.findInstance('"+this.eltId+"').slideUp()", this.nbSecs*1000);
				}
				this.isFreezed = false;
			}
			this.slideUp = function(){
				if(this.isFreezed==false){this.goOneUp();}
			}
			this.goOneUp = function(){
				var newOffset = this.currentYOffset+this.pictureHeight;
				if(newOffset==(this.nbPictures*this.pictureHeight)){newOffset = 0;}
				this.currentYOffset = newOffset;

				//this.mainElt.style.backgroundPosition = '0px -'+this.currentYOffset+'px';
				this.sliddingElt.style.top = '-'+this.currentYOffset+'px';
			}
		}
		PhotoSlider.instancesList = new Array();
		PhotoSlider.findInstance = function(p_instName){return PhotoSlider.instancesList[p_instName];}