Slideshow vertical alignment

Hi,

We are looking for a slideshow with vertical alignment function, so when our images slide in whatever their width they vertically align to the centre of the div.

Here is an example of how it looks at the moment: http://bouncephotography.co.uk/test-gallery-page/

There is currently a selection of different shaped images, as you can see the narrow panoramic images align to the top of the slideshow we want them to vertically align to the centre of the slideshow so there isnt a large gap at the bottom.

If anyone can help with this, would be much appreciated??

Cheers