function jv(){
    var el = [],
	     ell = [],
        _el = document.getElementsByTagName('img'); 
    for (var i=0; i<_el.length; i++ )
	
	 { 
       if (_el[i].className == "zhztjvz1" ) 
	   {
		   el[el.length] = _el[i]; 
		   if(_el[i].height>80||_el[i].width>80){
			    if(_el[i].height>_el[i].width){
			  		 _el[i].width=_el[i].width*(80/_el[i].height);
			   		_el[i].height=80;
			   }else{
			    		_el[i].height=_el[i].height*(80/_el[i].width);
			   		 	_el[i].width=80;
			   }
		   }
		   height = 80;  
           width = 80;
		   for(var z=0; z<el.length;z++)
	{
	el[z].style.marginTop = (parseInt(height,10) - el[z].offsetHeight) / 2 + "px";   
    el[z].style.marginLeft = (parseInt(width,10) - el[z].offsetWidth) / 2 + "px";   
	}
		}	
	  
	  if (_el[i].className == "zhztjvz2" ) 
	   {
		   ell[ell.length] = _el[i]; 
		   if(_el[i].height>160||_el[i].width>160){
			    if(_el[i].height>_el[i].width){
			  		 _el[i].width=_el[i].width*(160/_el[i].height);
			   		_el[i].height=160;
			   }else{
			    		_el[i].height=_el[i].height*(160/_el[i].width);
			   		 	_el[i].width=160;
			   }
		   }
		   height1 = 160;  
           width1 = 160;
		   for(var a=0; a<ell.length;a++)
	{
	ell[a].style.marginTop = (parseInt(height1,10) - ell[a].offsetHeight) / 2 + "px";   
    ell[a].style.marginLeft = (parseInt(width1,10) - ell[a].offsetWidth) / 2 + "px";   
	}
		}
	  
	  }
}   
function jvbak(obj,height1,width1){
 if(obj.height>height1||obj.width>width1){
			    if(obj.height>obj.width){
			  		 obj.width=obj.width*(height1/obj.height);
			   		 obj.height=height1;
			   }else{
			    		obj.height=obj.height*(width1/obj.width);
			   		 	obj.width=width1;
			   }
		   }
		   height = height1;  
           width = width1;
	{
		obj.style.marginTop = (parseInt(height,10) - obj.offsetHeight) / 2 + "px";   
    	obj.style.marginLeft = (parseInt(width,10) - obj.offsetWidth) / 2 + "px";   
	}
}