how to solve subsrcipt indices problem in iswt operation

I got the following error while computing inverse iswt operation.'Subscript indices must either be real positive integers or logicals.' I check the index by running 'whose variable' syntax and confirmed that the input index are logical. Please any one provide your valuable guidance.

image=imread('referenceframe.jpg');
image1=imread('currentframe.jpg');
image=imresize(image,[244 324]);
image1=imresize(image1,[244 324]);
% Do color conversion from rgb to hsv
        x=rgb2hsv(image);
        y=rgb2hsv(image1);
        % Split the hsv component to h,s,v value
        Hx = x(:,:,1);
        Sx = x(:,:,2);
        Vx = x(:,:,3);
        Hy = y(:,:,1);
        Sy = y(:,:,2);
        Vy = y(:,:,3);

          % Calculate a difference between this frame and the background.
          dh=abs(Hx- Hy);
          ds1=abs(Sx- Sy);
          dv1=abs(Vx- Vy);
  % Perform the 'swt'
          [as,hs,vs,ds] = swt2(ds1,2,'haar');
          [av,hv,vv,dv] = swt2(dv1,2,'haar');
  %Compute the skewness value of 'swt of v'
          sav1=skewness(av(:));
          shv1=skewness(hv(:));
          svv1=skewness(vv(:));
          sdv1=skewness(dv(:));
  %Perform the thresholding operation
  for i = 1:244
      for j = 1:324
           b=(av(i,j)>=sav1);
          c=(hv(i,j)>=shv1);
          d=(vv(i,j)>=svv1);
          e=(dv(i,j)>=sdv1);
  recv = iswt2(b,c,d,e,'haar');
      end
  end

[KSSV]

You have not specified which line...and also we don't have the images which you have specified in the code to check.

[SHOBA MOHAN]

i got the error While executing the code

recv = iswt2(b,c,d,e,'haar'); .

I am attaching the image for your kind reference.

[KSSV]

b,c,d and e are always 0's....you need to send some non zeros to iswt2.

[SHOBA MOHAN]

I followed the algorithm given in the paper for detecting and removing shadows. I have done till shadow detection thresolding part and shadow removal yet to be done. Can you please check whether i coded correctly the algorithms? what is wrong with that code? provide your suggestion.

Answer 1

[Walter Roberson]

In newer versions, the code instead complains that the first input was logical when real finite double values were expected.

[KSSV]

The values of b,c,d and e are always 0's.....there is not non zero value to convert logical into double..

[Walter Roberson]

refimage=imread('referenceframe.jpg');
curimage1=imread('currentframe.jpg');
refimage=imresize(refimage,[244 324]);
curimage1=imresize(curimage1,[244 324]);
% Do color conversion from rgb to hsv
        x=rgb2hsv(refimage);
        y=rgb2hsv(curimage1);
        % Split the hsv component to h,s,v value
        Hx = x(:,:,1);
        Sx = x(:,:,2);
        Vx = x(:,:,3);
        Hy = y(:,:,1);
        Sy = y(:,:,2);
        Vy = y(:,:,3);

            % Calculate a difference between this frame and the background.
            dh=abs(Hx- Hy);
            ds1=abs(Sx- Sy);
            dv1=abs(Vx- Vy);
    % Perform the 'swt'
            [as,hs,vs,ds] = swt2(ds1,2,'haar');
            [av,hv,vv,dv] = swt2(dv1,2,'haar');
    %Compute the skewness value of 'swt of v'
            sav1=skewness(av(:));
            shv1=skewness(hv(:));
            svv1=skewness(vv(:));
            sdv1=skewness(dv(:));
    %Perform the thresholding operation
    b = 0 + (av >= sav1);
    c = 0 + (hv >= shv1);
    d = 0 + (vv >= svv1);
    e = 0 + (dv >= sdv1);
    recv = iswt2(b,c,d,e,'haar');
    imagesc(recv)

[SHOBA MOHAN]

Thanks Walter. Now, the iswt syntax works. I have included the threshold for shadow removal as per algorithm given in the attached article also given the same code here.

sas=skewness(as(:));
        shs=skewness(hs(:));
        svs=skewness(vs(:));
        sds=skewness(ds(:));
        f=(as>=sas);
        g=(hs>=shs);
        h=(vs>=svs);
        z=(ds>=sds);
    k = 0 + (b&f);
    l = 0 + (c&g);
    m = 0 + (d&h);
    n = 0 + (e&z);
recs= iswt2(k,l,m,n,'haar');
de_shadow1_hsv=cat(3,dh,recs,recv);
         de_shadow1=hsv2rgb(de_shadow1_hsv);
         de_shadow1=rgb2gray(de_shadow1);

I am attaching the 'recs','recv' and output image for your kind reference. It is noticed that shadow presents in the'output image'. Can you suggest me why shadow presents in output though we applied shadow removal threshold.