Would it be possible to use this program to forward project a 3D image where dx=dy, but dx=dy!=dz? Right now, my parameters are:
%% Parameter setting %%
param.nx = 400;
param.ny = 400;
param.nz = 66;
%The real detector panel pixel density (number of pixels)
param.nu = 400;
param.nv = 400;
% Detector setting, according to Varian Trilogy OBI (real size)
param.su = 350; % mm
param.sv = 350; % mm
% X-ray source and detector setting
param.DSD = 1500; % Distance source to detector
param.DSO = 1000; % X-ray source to object axis distance
% This confusing stuff
param.sx = param.nx*res; % mm
param.sy = param.ny*res; % mm
param.sz = param.nz*res; % mm
but this doesn't create the correct forward projections, so far as I have been able to check. Am I trying to do something that is impossible in image processing?
That's a good point.
This factor is used in the weighted backprojection for fan-beam and cone-beam geometries.
(see Jiang Hsieh 2nd edition, Figs 3.35 (reason) and 3.37(geometry))
Result is similar compared to the previous one, In real geometry, this factor is not critical factor for the image, because CT rotates 360 deg (average factor ~ 1) as well as itself is close to 1.
However, I think I omitted it for fast calculation, soon I will fix it for accuracy.
Thanks a lot.
ps) you can directly send e-mail to me, it is sometimes difficult to check comments here.