I have 256*256 image. I had converted into 4*4 blocks. Now I have 64*64 blocks. And also I had converted each 4X4 into 16X1 column vector. Now I have 256 arrays, each have 16*1. I want to calculate mean value of first 8 arrays, then next 8 arrays,.

I=imread('cameraman.tif'); I=double(I); Im=size(I); %find the size of the image [nr nc nd]=size(I); % Divide into blocks disp(nr); disp(nc);

% Divide into blocks m=64; n=64; row=1; column=1; i=1; j=1; nn=0; for i=1:4:nr-3

    for j=1:4:nc-3

      block=I(i:i+3,j:j+3);

      disp(block)
      %convert 4X4 into 16X1 column vector
      tv=reshape(block,16,1);
      disp(tv)

      column=column+4;
      %  R = blkproc(tv,[1 8],@(x) mean(x(:)))       
     end

   row=row+4;

end

%B=mean(tv,8,[],16,256) %B=sepblockfun(I,[4,2],'mean'); disp(i) disp(j) R = blkproc(tv,[12 8],@(x) mean(x(:)))

[nr nc nd]=size®

[Matt J]

Please stick with your original post on this topic.