CT平行束重建图像

CT图像的平行束重建图像的重建算法，非常高

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%生成原始投影数据（shade）滤波重建 s-l
clear all
close all
load shade.mat;
figure                 
imshow（shade[]）
title（‘原始投影数据‘）;
                %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
                %%%%%%%%%%%%%%%%%S_L滤波器  256点
                %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
t=linspace（-128127256）;
filt=0.017*（sinc（t）/2-sinc（t/2）.^2/4）;
figure;
plot（filt）;
title（‘R__L 滤波函数‘）;
                %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
                %%%%%%%%%%%%%%%%%滤波处理中心裁减
                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（‘经过滤波处理后的投影数据‘）;
clear filt;
clear shade;
clear shade1_temp
clear shade_temp;
clear t

                %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
                %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
                %%%%%%%%%%%%%%%%反投影 点驱动
                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（‘重建后的图象‘）
                

load head.mat
figure
y1 = head（128:）;
imshow（head[]）
title（‘原始图象数据‘）;



figure
plot（x1‘r‘）
hold on
plot（y1）;
title（‘红---重建图象    蓝---原始图象‘）      

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----

     文件     249683  2009-05-21 18:05  平行束\原始头模数据\head.mat

     文件     283344  2009-05-21 19:06  平行束\投影数据\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\重建数据\re.mat

     目录          0  2012-09-17 23:51  平行束\原始头模数据

     目录          0  2012-09-17 23:51  平行束\投影数据

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

     目录          0  2012-09-17 23:51  平行束\重建数据

     目录          0  2012-09-17 23:51  平行束

----------- ---------  ---------- -----  ----

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