--- a
+++ b/combinedDeepLearningActiveContour/dim_reduction.m
@@ -0,0 +1,50 @@
+% dimension reduction using PCA
+clc
+clear all
+close all
+addpath('functions')
+%%
+load matFiles/training_data; 
+
+% total images
+I=t_Iroi;
+[x,y,z]=size(I);
+I1=reshape(I,x*y,z);
+
+% apply PCA
+N=size(I1,1);
+C=I1*I1'/N;
+[U,S,V]=svd(C);
+
+% reduce dimension
+n=90;
+I2=I1'*U(:,1:n);
+
+%save pca_results
+%% recover
+I3=I2*U(:,1:n)';
+I4=I3';
+I5=reshape(I4,x,y,z);
+imagesc(I5(:,:,1));colormap(gray)
+
+% total ROI
+B=t_yROI;
+[x,y,z]=size(B);
+B1=reshape(B,x*y,z);
+
+p2=pca(B1');
+B2=B1'*p2;
+
+% recover
+B3=B2*p2';
+B4=B3';
+B5=reshape(B4,x,y,z);
+figure
+imagesc(B5(:,:,2));colormap(gray)
+imagesc(B(:,:,2));colormap(gray)
+Br=imresize(B(:,:,2),40/256);
+Brr=imresize(Br,256/40);
+Brr=round(Brr);
+imagesc(Brr);colormap(gray)
+
+