I've dont some work with Maya and Matlab, I just ended up making a script that took coords of animated objects from Maya into a text file for importing into matlab. I'm not too sure that you can actually do what you are saying as the rendered images are independant from the coords in the 3D scene (though they are calculated for positionsl data of the pixels) from the commnand line. Though as I was not looking to get data from Maya into matlab directly i.e as maya computes the data porting it over as soon as it is done.

To do this you might need to do some work in the API to get the data out. I'm sure that there would be a way to port the data into something like a simulink node and then process this in Matlab (or using simulinks blocksets) though I'm not too sure.

I assume that you need to get some XYZ data accross from Maya into Matlab as soon as it is animated not as 2 sepperate bits of work?