Manipulating images (Tyre tracks - php... ish)

[PoorDoggie]

I want to make a tyre tracks image to go on roadbusters down the side where the "racing stripes" are at the moment. Now, they need to be dynamic, so that I can change the color of them. eg:

http://www.roadbusters.com/bb/templates/subSilver/images/bg.php?color=006400
http://www.roadbusters.com/bb/templates/subSilver/images/bg.php?color=AB0B15
etc...

I thought about having a picture of tyre tracks, but don't know if I can put a color "overlay" over a jpeg image, using php. Would this be possible? The background would always be black, and therefore an overlay shouldn't affect it. So basically, instead of dynamically generating some complicated tyre tracks in php, it would be easier to already have the jpeg img of them, and then just change the color using an overlay, if you get what I mean.

lol - a lot of people have told me how "crap" the tyre marks are on roadbusters, and so I decided that I can't be bothered to keep correcting people, lol - I would try and acctually turn them into tyre tracks! :D lol

Thanks
Tom