Radon Transformation - Digital Signal Processing for Medical Imaging Using Matlab - page 23

Fig. 1.25 Final reconstructed
image obtained from filtered
fanbeam projection with
C = 300

10. Figure 1.23 : β = B
β =

for various B (with filtering).
11. Figure 1.24 : Final fan-beam reconstructed image f

M 1

β

0

( r ,φ) without filtering.

12. Figure 1.25 : Final fan-beam reconstructed image f ( r ,φ) with filtering.

1.3.3.1 Fanbeamprojection.m

%load the original image
load VASIGIMAGE
C=C(1:1:255,1:1:255);
C=[zeros(128,511);zeros(255,128) C zeros(255,128);
zeros(128,511)];
C=double(C)/255;
figure
D=300;
maxiangle=atan(256/((D-255)+1));
B=zeros(511,511);
j=1;
range1=0:0.005:round(maxiangle/0.005)*0.005;
range2=sort(-1*range1);
ang=0:(2*pi)/359:2*pi;
angdeg=(ang/pi)*180;
for ang=angdeg(1:1:length(angdeg)-1)
t=0;
i=1;
A1=imrotate(C,ang,'crop');
%Computation of Beta
beta(j)=ang;
%Computation of delta
delta=[range2 range1(2:1:length(range1))];
for range=[range2 range1(2:1:length(range1))];