function zoomPicture(ImgD ,pwidth,pheight){ 
var image=new Image(); 
var iwidth = pwidth;
var iheight = pheight;
image.src=ImgD.src; 
if(image.width>0 && image.height>0){ 
if(image.width/image.height>= iwidth/iheight){ 
if(image.width>iwidth){   
ImgD.width=iwidth; 
ImgD.height=(image.height*iwidth)/image.width; 
}else{ 
ImgD.width=image.width;   
ImgD.height=image.height; 
} 
ImgD.alt=image.width+"×"+image.height; 
}else{ 
if(image.height>iheight){   
ImgD.height=iheight; 
ImgD.width=(image.width*iheight)/image.height;   
}else{ 
ImgD.width=image.width;   
ImgD.height=image.height; 
} 
ImgD.alt=image.width+"×"+image.height; 
   } 
} 
}