I want to read 24 images and stores value of omega,imou,nb into mat file, but some error in my program...

function [timeelapsed1] = matfileforallimages()
%create .mat file and calculates weights of each binary image in the database
clc;
clear all;
% database veins
nuser=4;
nrep=6;
path='C:\Program Files\MATLAB\R2013a\bin\img\PCA\my_PhD_Programs\DorsalVeinsDEMO\templates';
for iuser=1:nuser
    for irep=1:nrep
        nfichd=['binaryROImano-',num2str(iuser,'%.3d'),'-',num2str(irep,'%.3d')];
        nfichd=[path,'\',nfichd,'.bmp'];        
        image1=imread(nfichd,'bmp');
        %cd ..
        timeelapsed1=cputime;
        [irow,icol]=size(image1);
        S=reshape(image1, irow*icol, 1);
        %image mean
        imoy=[];
        imoy=mean(S,2);
        S=double(S);
        %eigen values and eigen vectors for the matrix L=S'S
        L=S'*S;
        [vv dd]=eig(L);
        v=[];
        d=[];
        for i=1:size(vv,2)
            if (dd(i,i)>1e-4)
                v=[v vv(:,i)];
                d=[d dd(i,i)]; 
            end
        end
        %sort eigen values of L=S'S
        [dtemp index]=sort(d,'descend');
        for i=1:length(d)
            vtemp(:,i)=v(:,index(i));
        end
        d=dtemp;
        v=vtemp;
        %normalize eigen vectors of L=S'S
        for i=1:size(v,2)    
            kk=v(:,i);
            temp=sqrt(sum(kk.^2));
            v(:,i)=v(:,i)./temp;   
        end
        %eigen values and eigen vectors for the covariance matrix C=SS'
        u=[];
        for i=1:size(v,2)
            temp=sqrt(d(i));
            u=[u (S*v(:,i))./temp];
        end
        %normalize eigen vectors of C
        for i=1:size(u,2)
            kk=u(:,i);
            temp=sqrt(sum(kk.^2));
            u(:,i)=u(:,i)./temp;
        end
        %number of eliminated components from the eigen base
        nb=0;
        %weights of database's images
        omega=[];
        for h=1:size(S,2)
            ww=[];
            for i=1:size(u,2)-nb
                t=u(:,i);
                Weight=dot(t,S(:,h)');
                ww=[ww;Weight]; 
            end
            omega=[omega,ww]; 
        end
        M=4;
        save('omega1', 'omega', 'imoy', 'u', 'nb', 'M') %omega contains the extracted features of database images
    end
end

[Geoff Hayes]

Balaji - please clarify what you mean by but some error in my program. What are the errors that you are observing? What is the expected behaviour of your code? Are you trying to store the omega, imou, etc. for each of the 24 images?

[Image Analyst]

It looks like it should save those variables into a file called 'omega1.mat' in the current folder. Does it not do that? Please copy and paste back here ALL the red text of your error message.

[Balaji M. Sontakke]

Yes sir, just am trying to store the omega,imou,nb,m for each of the 24 images. But only content of one image is stored, my output is like following... imoy x 1 u X 1 nb 0 omega 59.02 M 4

But i want output like this.. imoy x 1 u X 24 nb 0 omega X 24 M 4

What's wrong in my program i dont know...

[Balaji M. Sontakke]

what happen sir, It is not possible to store the omega,imou,nb,m for each of the images?

Answer 1

[Geoff Hayes]

Balaji - note that on each iteration of the second loop you are saving the data to file

 for iuser=1:nuser
      for irep=1:nrep
        ...
        M=4;
        save('omega1', 'omega', 'imoy', 'u', 'nb', 'M') %omega contains the extracted features of database images
      end
 end

which means that you are overwriting the data in the omega1 file on each of these iterations. So the only data in this file corresponds to the 24th iteration.

If you want to store all of this data to the same file, then I suggest that you create some cell arrays (in case your matrix dimensions change on any iteration) to store the data from each iteration. Once you have finished looping over all of these files, then save the cell array data to file (doing this outside of the outer for loop.

[Balaji M. Sontakke]

Dear Geoff, Thanks for your answer that really works