Jpeg to 3D surface

I have a bathymetric map in the form of a jpeg image. What I would like to do is import this into Matlab, for Matlab to recognise the colour map and plot a 3D surface of my image. Can anyone describe the best way to do this? I am not a big user of Matlab, I just need to do this one thing for my project.

(I have managed so far to import the image but the axis are all wrong. When I try and change them it changes my image size. I need the image to stay put and to change the values on the scale Then plot a 3d surface of it)

[Ethan]

Sorry pal