MATLAB: How to solve the following error,’Conversion to cell from unit8 is not possible’

color normalizationmontagemultiple images

I need to perform color normalization on 55 images.
This is my code for color normalization:
function img = colornormalization(img_in)
meanStdTarget=[77.5121  270.5718; 8.9287 -23.6535; 2.9664 8.3857];
binry = rgb2gray(img_in);
binry((binry>=215)) = 0;
binry((binry~=0)) = 1;
binry = ~binry;
img=colorCorrect(img_in,meanStdTarget,binry);
img=uint8(img*double(intmax('uint8')));
end
function img=colorCorrect(imgO,meanStdTarget,whiteMask)
if isequal(class(imgO),'uint8')
    imgO=double(imgO)/double(intmax('uint8'));
end
lStd=meanStdTarget(1,1);lMT=meanStdTarget(1,2);
aStd=meanStdTarget(2,1);aMT=meanStdTarget(2,2); 
bStd=meanStdTarget(3,1);bMT=meanStdTarget(3,2);
if whiteMask ~=-1
    nwMask =~ whiteMask;
else
    nwMask=true(size(imgO,1),size(imgO,2));
end
indexWhitePixel=nwMask==false;
labO=convertRGBToLAB(imgO);
labO_l=labO(:,:,1);
labO_a=labO(:,:,2);
labO_b=labO(:,:,3);
if any(indexWhitePixel(:))
    labO_l=labO_l(nwMask);
    labO_a=labO_a(nwMask);
    labO_b=labO_b(nwMask);
end
lsbO=std(labO_l(:));lMO=mean(labO_l(:));
asbO=std(labO_a(:));aMO=mean(labO_a(:));
bsbO=std(labO_b(:));bMO=mean(labO_b(:));
labO(:,:,1)=((labO(:,:,1)-lMO)/lsbO)*lStd+lMT;
labO(:,:,2)=((labO(:,:,2)-aMO)/asbO)*aStd+aMT;
labO(:,:,3)=((labO(:,:,3)-bMO)/bsbO)*bStd+bMT;
RGB=convertLABToRGB(labO);
RGB_r=RGB(:,:,1);
RGB_g=RGB(:,:,2);
RGB_b=RGB(:,:,3);
imgR=imgO(:,:,1);
imgG=imgO(:,:,2);
imgB=imgO(:,:,3);
imgR(nwMask)=RGB_r(nwMask);
imgG(nwMask)=RGB_g(nwMask);
imgB(nwMask)=RGB_b(nwMask);
img(:,:,1)=imgR;
img(:,:,2)=imgG;
img(:,:,3)=imgB;
end
function imgLAB=convertRGBToLAB(imgT)
imgR=imgT(:,:,1);
imgG=imgT(:,:,2);
imgB=imgT(:,:,3);
channelVectors=[imgR(:)';imgG(:)';imgB(:)'];
rgbToLMS=[0.3811 0.5783 0.0404; 0.1967 0.7244 0.0782; 0.0241  0.1288  0.8444];
LMS=rgbToLMS * channelVectors;
lmsToLab1=[1/sqrt(3) 0 0; 0 1/sqrt(6) 0; 0 0 1/sqrt(2)];
lmsToLab2=[1 1 1;1 1 -2; 1 -1 0];
LAB=lmsToLab1 * lmsToLab2 *LMS;
imgLAB(:,:,1)=reshape(LAB(1,:),[size(imgT,1) size(imgT,2)]);
imgLAB(:,:,2)=reshape(LAB(2,:),[size(imgT,1) size(imgT,2)]);
imgLAB(:,:,3)=reshape(LAB(3,:),[size(imgT,1) size(imgT,2)]);
end
function imgRGB=convertLABToRGB(imgLAB)
labToLMS1=[1 1 1;1 1 -1;1 -2 0];
labToLMS2=[1/sqrt(3) 0 0; 0 1/sqrt(6) 0; 0 0 1/sqrt(2)];
imgL=imgLAB(:,:,1);
imgA=imgLAB(:,:,2);
imgB=imgLAB(:,:,3);
LAB=[imgL(:)';imgA(:)';imgB(:)'];
LMS=labToLMS1*labToLMS2*LAB;
lmsToRGB=[4.4679 -3.5873  0.1193; -1.2186  2.3809 -0.1624; 0.0497 -0.2439  1.2045];
RGB=lmsToRGB * LMS;
imgRGB(:,:,1)=reshape(RGB(1,:),[size(imgLAB,1) size(imgLAB,2)]);
imgRGB(:,:,2)=reshape(RGB(2,:),[size(imgLAB,1) size(imgLAB,2)]);
imgRGB(:,:,3)=reshape(RGB(3,:),[size(imgLAB,1) size(imgLAB,2)]);
imgRGB=imgRGB/double(intmax('uint8'));
end
Now in a another matlab file I am writing the code for reading all 55images and then processing it.
addpath('myfiledirectory');
fileFolder = 'myfiledirectory';
   dirOutput = dir(fullfile(fileFolder,'*.tif')); 
     store={1:55};
     c={1:55};
     for k = 1 : length(dirOutput)
    A = dirOutput(k).name;
    B= fullfile(fileFolder,A);
    c(i)=imread(B);
   store(i)=colornormalization(c(i));
     end
      monatge(store,'size',[5,11]);

Best Answer

Instead of
c={1:55};
use
c = cell(55,1);
Instead of
    c(i)=imread(B);
use
    c{i} = imread(B);
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