%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%生成原始投影數據（shade）濾波重建?s-l
clear?all
close?all
load?shade.mat;
figure?????????????????
imshow（shade[]）
title（‘原始投影數據‘）;
????????????????%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
????????????????%%%%%%%%%%%%%%%%%S_L濾波器??256點
????????????????%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
t=linspace（-128127256）;
filt=0.017*（sinc（t）/2-sinc（t/2）.^2/4）;
figure;
plot（filt）;
title（‘R__L?濾波函數‘）;
????????????????%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
????????????????%%%%%%%%%%%%%%%%%濾波處理中心裁減
????????????????tic
shade_temp?=?zeros（768180）;
shade_temp（257:512:）?=?shade;
for?n?=?1:180;
????shade1_temp（:n）?=?conv（shade_temp（:n）filt‘）;
end
shade1?=?shade1_temp（385:640:）;
figure;
imshow（shade1[]）;
title（‘經過濾波處理后的投影數據‘）;
clear?filt;
clear?shade;
clear?shade1_temp
clear?shade_temp;
clear?t

????????????????%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
????????????????%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
????????????????%%%%%%%%%%%%%%%%反投影?點驅動
????????????????d_th?=?pi/180;
????????????????re?=?zeros（256256）;
????????????????for?view??=??1:180
????????????????????l?=?（（128.5）*sin（（view-1）*d_th））+（（128.5）*cos（（view-1）*d_th））-128.5;
????????????????????l_temp（view）?=?l;
????????????????????for?x?=?1:256
????????????????????????for?y?=?1:256
????????????????????????????n?=?（x-1）*sin（（view-1）*d_th）+（y-1）*cos（（view-1）*d_th）-l;
????????????????????????????if?（1????????????????????????????????nn?=?fix（n）;
????????????????????????????????n0?=?n-nn;
????????????????????????????????re（xy）?=?re（xy）+（1-n0）*shade1（nnview）+n0*shade1（nn+1view）;
????????????????????????????else?re（xy）?=?re（xy）;
????????????????????????????end
????????????????????????end
????????????????????end
%?????????????????????figure
%?????????????????????imshow（re[]）
????????????????end
????????????????toc
figure
x1?=?re（128:）;
imshow（re[]）
title（‘重建后的圖象‘）
????????????????

load?head.mat
figure
y1?=?head（128:）;
imshow（head[]）
title（‘原始圖象數據‘）;



figure
plot（x1‘r‘）
hold?on
plot（y1）;
title（‘紅---重建圖象????藍---原始圖象‘）??????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件?????249683??2009-05-21?18:05??平行束\原始頭模數據\head.mat

?????文件?????283344??2009-05-21?19:06??平行束\投影數據\shade.mat

?????文件???????2246??2009-06-07?21:04??平行束\程序\rlp_t.m

?????文件?????495128??2009-06-18?13:19??平行束\重建數據\re.mat

?????目錄??????????0??2012-09-17?23:51??平行束\原始頭模數據

?????目錄??????????0??2012-09-17?23:51??平行束\投影數據

?????目錄??????????0??2012-09-17?23:51??平行束\程序

?????目錄??????????0??2012-09-17?23:51??平行束\重建數據

?????目錄??????????0??2012-09-17?23:51??平行束

-----------?---------??----------?-----??----

??????????????1030401????????????????????9