how to count the png files in windows page by using selenium webdriver

how to count the png files in windows page by using selenium webdriver

how to count the png files in windows page by using selenium webdriver
http://www.thefind.com/search?query=camera
go to above website and count the number of camera present in page by
using seleniumwebdriver program
driver.get("http://www.thefind.com/search?query=camera");
List<WebElement> wb=driver.findElements(By.tagName("a"));
System.out.println(wb.size());