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I want to partition a PGM image into overlapping blocks and do a DCT transformation to every block. Then I want to take the first column of each DCT matrix and put them all to a new matrix.

I have read the answer to the post: How to partition an image to 64 block in matlab, but I am not sure it's working properly. Can I use blockproc function to make overlapping block and if I can how am I supposed to use it?

I would prefer an answer with for loops.

Community
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Vicky K
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1 Answers1

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I=im2double(rgb2gray(imread('yourimage.png'))); %select channels separation

%%%for non-overlapping blocks

fun = @(block_struct) dct2(block_struct.data);

imageY =(blockproc(I,[8 8],fun));

BY=im2col(imageY,[8 8],'distinct');

FinalOP=BY(1:8,:);

%dct-8x8 ,if you want u can choose [64 64].
%you need the first column of dct?.so ,i.e 8 values of dct in this case.

for overlapping blocks: use 'sliding' but you get memory problem. then you have to use your own for loop.

Amro
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pradeep
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