[Rtk-users] About the Elekta Reconstruction DBF file

[雅之 服部]

Thank you for your reply.

I checked RTK 3D circular projection geometry doc and understood.

I have another question.
After setting the geometry from the DBF file and reading the raw projection
data from .his file,
How do you convert the pixel values of the projection data to values for
reconstruction?
The pixel values in the .his file appear to have 16-bit values.
Is the value of the raw data the numerator as it is, and the maximum value
in the image as the denominator and the negative logarithm?

Or is the value of raw data (probably a logarithmic system) once made into
a linear system using the unique conversion table of the elekta system?
I checked  rtkElektaSynergyRawLookupTableImageFilter.h  and
ElektaSynergyLookupTableImageFilter.h  ,
 but I couldn't understand the difference between each source code because
I didn't study C ++ yet.

Best regards.

masa

2021年12月1日(水) 0:21 Simon Rit <simon.rit at creatis.insa-lyon.fr>:

> Hi,
> Yes, this mailing list is meant for this kind of questions.
> Only this information is used, see here
> <https://github.com/SimonRit/RTK/blob/master/src/rtkElektaSynergyGeometryReader.cxx#L72-L74>
> .
> To understand the meaning, you can check that it's used here
> <https://github.com/SimonRit/RTK/blob/master/src/rtkElektaSynergyGeometryReader.cxx#L92>.
> Yes, it corresponds to DetectorOffsetX and DetectorOffsetY in the figure of
> this documentation <http://www.openrtk.org/Doxygen/DocGeo3D.html> for
> each projection.
> Simon
>
> On Tue, Nov 30, 2021 at 2:28 PM 雅之 服部 <masayuki.h.0215 at gmail.com> wrote:
>
>> Dear rtk-users,
>>
>> I'm masa at japan.
>>
>> Is it okay to email General Technical Questions about RTK here?
>>
>> I'm working on RTK elekta reconstruction, but I'm new to C ++, so I don't
>> understand the specifics.
>> I downloadedIMAGE.DBF, FRAME.DBF and looked at the contents.
>> I understand that I am using angle information. But I didn't know what
>> U_CENTER and V_CENTER meant.
>>
>> Are they the offset numbers for each angle of the detector?
>> Also, which information is used for reconstruction from those two files?
>>
>> Thank you very much in advance.
>>
>> masa at japan
>> _______________________________________________
>> Rtk-users mailing list
>> Rtk-users at public.kitware.com
>> https://public.kitware.com/mailman/listinfo/rtk-users
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://public.kitware.com/pipermail/rtk-users/attachments/20211202/3798ea6f/attachment.htm>