How to get the Width and Height of Images or Elements using selenium webdriver

@Test
public void WidthndHight() throws Exception 
{
driver.get("http://seleniumsubbu.blogspot.in/");
driver.findElement(By.linkText("About Us")).click();
Thread.sleep(3000);
Dimension dimesions=driver.findElement(By.className("image-style-none")).getSize();
System.out.println("Width : "+ dimesions.width); //Print the Width of the Image
System.out.println("Height : "+ dimesions.height); //Print the Height of the Image
}