How to get the scrolling effect you see on theme demo pages?

Hi, on a few theme sales pages, they have a cool effect, when you hover over the demo image, it scrolls up within a window of a desktop PC, for example.
There is a good example on this site here:
My question is, does anyone know how to do this or if there are any wordpress plugins available for this task?

Thanks in advance

On the page you linked to they have animated the background-position CSS property on hover.

.background-image {
    background-position: center top;
    transition: all 2.5s ease-in;
.background-image:hover {
   background-position: center bottom;