[Rtk-users] JosephForwardProjectionImageFilter - output intensity problem

[Thibault Pelletier]

Hi everyone,

I'm currently implementing the NMAR algorithm using RTK and I have a
problem regarding the forward projection step.

To make sure my building blocks are correct, I decided to first read my
projection stack using the rtk::ProjectionsReader class, do a FDK Cone Beam
reconstruction and forward project this reconstructed image using the
rtk::JosephForwardProjectionImageFilter class.

I then compare the images that I have after reading my projection stack
with the images that I have after my JosephForwardProjectionImageFilter
pass.

My problem is that the values I obtain are quite different (sinogram of the
images attached).
The forward projected images are overall 1.7 times brighter than the reader
images.

Does anyone have an insight on what I could be doing wrong?

Thanks in advance,
Thibault
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