changing header image depending on node

Hi,

In the header where the Logo, Site name and Site slogan appears, I would like to have my header banner (or background image) to change every time with the page that is navigated to.

Lets say I have a page for dogs, for that page I would like to show little puppies in the header.
Then, when someone clicks on cats I want to show cats on top.
Cows for the cows page, horses for the horses page ... etc.

Right now I use a randomizer, that gives me a random picture from a pool of pictures, but that means that when someone clicks on cats, they might get a horse, a cow or a dog picture randomly.

Is there a way to get different images in the header related to the different pages that are in the site?

Thanks.