[gate-users] spblurring

[Christian Wietholt]

Dear Mikhail, 

Good to hear that I am not the only one with this problem. Well, I never got 
the spatial blurring in the interfile output to work. I probably would have 
to dig deeper in the source code of GATE to do so. What I ended up doing is 
writing a program to extract the detector "counts" from the gateSingles.dat 
file. If you wish, I can provide the source code. 

The correction I made to the GateSpblurring.cc fixes a different problem, 
where the spatial blurring only works in the Y dimension. This is more a 
hotfix, I think some more work is needed to make it 100% correct. I am in 
contact with the developer of this file. If you manage to extract the 
"counts" from gateSingles.dat, I would be more than interested in knowing 
your results and if you also observe that the blurring only works in one 
dimension. 

Please let me know if you need any further help. 

Regards, 

Christian

> I just noticed this thing with the Spatial blurring while doing some test
> run s with GE Millennium spect camera. I constructed a collimator only with
> one hole and looked at the results of a simulation from a spherical volume
> source. The camera is in Y-Z plane. I set up the digitizer as follows:
>
> #	A D D E R
> /gate/digitizer/Singles/insert adder
>
> #       R E A D O U T
> /gate/digitizer/Singles/insert readout
> /gate/digitizer/Singles/readout/setDepth 1
>
>
> #      E N E R G Y   B L U R R I N G
> /gate/digitizer/Singles/insert blurring
> /gate/digitizer/Singles/blurring/setResolution 0.15
> /gate/digitizer/Singles/blurring/setEnergyOfReference 140. keV
>
> # S P A C I A L  B L U R R I N G
> /gate/digitizer/Singles/insert spblurring
> /gate/digitizer/Singles/spblurring/setSpresolution  30.0 mm
> /gate/digitizer/Singles/spblurring/verbose 1
>
> First of all I don't get ANY blurring in the interfile projection output.
> Does anyone knows why? Second, when I look at the ASCII gateSingles.dat
> file I see the correct blurring in the Y direction but absolutely no
> blurring in the Z direction.
>
> Christian,
>
> I saw your postings on this issue. Did you manage to fix the problem? Does
> you correction  to the code fix this bug? :
>
> GateSpblurring.cc:
> G4double PzNew = G4RandGauss::shoot(Pz,m_spresolution/2.35);
>
> Thanks
>
>
>
>
>
>
> Mikhail A. Shilov
> The Johns Hopkins University
> Department of Radiology
> Division of Medical Imaging Physics
> Tel:  443-287-7315
> Fax:  410-614-1977
> mailto: mshilov1 at jhmi.edu
>
>
> ------------------------------
>
> _______________________________________________
> gate-users mailing list
> gate-users at lphe1pet1.epfl.ch
> http://lphe1pet1.epfl.ch/mailman/listinfo/gate-users
>
> End of gate-users Digest, Vol 17, Issue 22
> ******************************************