[Gate-users] Voxelised source problem with ASCII input

[David Oxley]

Dear all, 

I am trying to implement a voxelised source of positrons into a cylindrical PET scanner using the ASCII method of defining the source and a linear translator.
my question follows on from a discussion in the archives between Simon Stute and Ismet Isnaini (http://article.gmane.org/gmane.comp.science.opengate.user/1356/match=voxelized+source+ascii, last post 22-Feb-2011) where they concluded reading in a voxelised source using the ascii method had a bug in it. 

I am not sure if I am seeing the same bug, but I am not sure how GATE knows my voxel size and I see large amounts of my data are compressed into the early entries of my source. 

First, I am wondering if there have been any developments on this bug as using an ASCII file really sounds much easier.

If not, then I was hoping for more information about this InterFile alternative. In the voxelised source section of the manual it appears there is only one interfile, in this case hof.h33. But earlier in the manual there is a link to http://www.colin-studholme.net/software/rview/rvmanual/fileform.html#interfile , where there is talk of a header and a different image for each slice. I want my source to be a matrix, 100 x 100 x 100 voxels with a voxel size of 1mm x 1 mm x 1mm and I know what the activity should be for each of the voxels. 
Does this mean if I have an ascii file  with 100^3 entries, I need to make 100 images ending in .IMG for the InterFie format? Are these saved as binary or ascii? Is the header binary? 

Perhaps someone has come across this problem before or knows more about this InterFile format than I do. 

Just finally, I would rather not use the InterFile format, if someone has fixed the bug or has been able to use the ascii voxelised source without problems, I would greatly appreciate their help. 

Thanks in advance to you all for taking the time to assist. 

Kind regards,

Dave

================================= 

Dr. David Oxley

Postdoctoral Researcher 
Kernfysisch Versneller Instituut
Zernikelaan 25
NL-9747 AA Groningen
The Netherlands

d.c.oxley at kvi.nl
d.c.oxley at rug.nl