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How can I concatenate multiple histograms in a for loop into 1 histogram using matlab

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fy_mad
fy_mad on 12 Aug 2017
Edited: fy_mad on 9 Dec 2017
I am new to MATLAB. I have calculated 25 histograms using imhist function, which are created from subdividing the image into 25 blocks (1block=1histogram) using for loop. How can I concatenate these histograms on the same graph to make one histogram where for instance, the histogram for the first block stretches on the x axis from 0 to 255, the histogram for the second block stretches from 256 to 511, and so on until the 25th block. How can I do this?
I had found a solution like this https://stackoverflow.com/questions/30951480/how-to-concatenate-3-histograms-on-the-same-graph-in-matlab but my problem is I calculated all 25 histograms using for loop and I don't know what variable should I pass so that I can concatenate all histograms in 1 long histogram as I want it to be.
This is what I had done:
%declare variable
B=12; %B represent the block size
overlapp=3; %overlapping block is slid by 3 pixels along the image
nob=0; %no of blocks
%get input from grayscale image
gray_path = 'D:\gray_image_folder\*.png';
total_gray_images=dir(gray_path);
for noOfGRAYimage = 1:length(total_gray_images)
% Specify images names with full path and extension
grayfilename=strcat('D:\gray_image_folder\', total_gray_images(noOfGRAYimage).name);
grayImage = imread(grayfilename);% Read gray images
[r, c, p]=size(grayImage);
for i=1:overlapp:(r-B)+1;
% fprintf('i = %d\n', i);
% numberofblock = sprintf('%s_%d','block',nob)
for j=1:overlapp:(c-B)+1;
% fprintf('j = %d\n', j);
nob=nob+1;
fy_mad(nob).block=grayImage(i:i+B-1,j:j+B-1); %partition (12x12) of blocks
fy_mad(nob).position=[i j];
fy_mad(nob).index=nob;
[rb, cb]=size(fy_mad(nob).block); %[12,12]
localBinaryPatternImage = fy_mad(nob).block;
%call function LBP
LBP_centre = LBP (localBinaryPatternImage);
figure;imhist(uint8(LBP_centre)) %histogram for each block
% How to concatenate all histograms?
%////
end
end
end
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