function formatimg(obj,w,h){
	var image=new Image(); 
	image.src=obj.src; 
	if(image.width>0 && image.height>0){ 
		flag=true; 
		if(image.width/image.height>= w/h){ 
			if(image.width>w){ 
				obj.width=w; 
				obj.height=(image.height*w)/image.width; 
			}else{ 
				obj.width=image.width; 
				obj.height=image.height; 
			} 
		}else{ 
			if(image.height>h){ 
				obj.height=h; 
				obj.width=(image.width*h)/image.height; 
			}else{ 
				obj.width=image.width; 
				obj.height=image.height; 
			} 
		} 
	} 
}