Combining two images (ultrasound blood flow)

Hey there,

I'm doing a project on blood flow velocity in ultrasound. I Need to display a color flow map, with a colorbar displaying what velocity the colors indicate.

I calculated both the stationary part of the image and set all the none stationary parts to zero like such:

m_log    = v_img < 0.01;            % Logical matrix of where the velocity 
                                    % is not present (or close to not).

m_img    = m_img.*m_log;            % All pixels where movement is present
                                    % is set to zero.

m_img is the stationary part, and v_img is the velocty part. Now i need to make a combined view of the two, and preferably using two different colormaps, since I'm only interested in showing a colorbar for the moving tissue (blood flow). I can get a combined view by adding them, but how to control colormap and keeping the velocity data in the same scale, is simply beoynd what I can figure out how to do. Does anyone have any smart suggestions for what to do, or just a hint on what to look at?

- Jake