%本程序用于生成系統(tǒng)矩陣A
clc
clear
N=100;%圖像大小?N*N
Ma=12;%掃描角度數(shù)（01530，...，165度）
Md=ceil（N/sqrt（2））*2;
NS=N*N;
MS=Ma*Md;
Ang=linspace（0180-180/MaMa）*pi/180;
Dis=-Md/2:Md/2;?%掃描間距為1

X_Vector=-N/2:N/2;
X_Vector1=ones（1N+1）;
XMap=X_Vector‘*X_Vector1;
XMap=XMap‘;
YMap=-XMap‘;
tic
RMap=zeros（MaN+1N+1）;
for?Ai=1:Ma?%射線角度
????RMap（Ai::）=cos（Ang（Ai））.*XMap+sin（Ang（Ai））.*YMap;
end

A=zeros（NSMS）;???????%系統(tǒng)矩陣
for?Ni=1:N%像素行
????for?Nj=1:N?%像素列
????????for?Ai=1:Ma?%射線角度
????????????DisPix=[RMap（AiNiNj）?RMap（AiNi+1Nj）?RMap（AiNiNj+1）?RMap（AiNi+1Nj+1）];
????????????DisPixMax=max（DisPix）;
????????????DisPixMin=min（DisPix）;
????????????DisInd=find（（Dis<=DisPixMax）?&（Dis>DisPixMin））;
????????????if?~isempty（DisInd）
????????????????PixInd=（Ni-1）*N+Nj;
????????????????for?DisIndi=1:length（DisInd）
????????????????????ProInd=（Ai-1）*Md+DisInd（DisIndi）;
????????????????????
????????????????????
????????????????????DisPixDiff=DisPix-Dis（DisInd（DisIndi））;
???????????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2015-01-19?17:57??上傳\
?????文件???????18238??2014-09-05?20:07??上傳\FBP.bmp
?????文件????????2198??2015-01-19?17:56??上傳\GenerateSIRTSystemMatrix.m
?????文件????????1540??2015-01-19?17:57??上傳\SIRTOnce.m
?????文件????????1678??2015-01-19?17:54??上傳\SIRTOnceSTD.m
?????文件???????17462??2014-09-05?19:58??上傳\SITR100.bmp
?????文件???????11078??2014-09-08?19:38??上傳\原始SP.bmp