[Gate-users] STIR: Gating system matrix

[Kris Thielemans]

> Hello,
> I am using STIR software to reconstruct PET images.
> I would like to read and save Ray Tracing Matrix system.
> Did somebody do this before?
> I appreciate any help.

seems more like a STIR question than GATE...

This is a non-trivial problem. you have to store the matrix in a sparse way
of course. Even then, it easily grows too large unless you use symmetries. I
don't know of any standard file-format that would be able to cope with both
of these issues. Of course, for 2D, you could get away with only sparseness.

So, I wrote some code for storing the matrix in a STIR specific binary
format (with an interfile type header). It introduces a new STIR class
(ProjMatrixByBinFromFile). I am not entirely happy with it (but I hardly
ever am happy with my code anyway), but I will include it into the very soon
to be release STIR 2.0 beta. It would need extra work to get it into a
full-blown solution, but I don't have the time for that. Feel free to modify
the code to your needs, and if it's any good, to contribute it back.

Kris