from selenium import webdriver

import time

def capture(url, save_fn="capture.png"):

    browser = webdriver.Firefox()  # Get local session of firefox

    browser.set_window_size(1200, 900)

    browser.get(url)  # Load page

    browser.execute_script("""

    (function () {

      var y = 0;

      var step = 100;

      window.scroll(0, 0);

      function f() {

        if (y < document.body.scrollHeight) {

          y += step;

          window.scroll(0, y);

          setTimeout(f, 50);

        } else {

          window.scroll(0, 0);

          document.title += "scroll-done";

        }

      }

      setTimeout(f, 1000);

    })();

  """)

    for i in xrange(30):

        if "scroll-done" in browser.title:

            break

        time.sleep(1)

    browser.save_screenshot(save_fn)

    browser.close()

if __name__ == "__main__":

    capture("http://www.jb51.net")