how to divide a grayscale image into 8*8 blocks and return it from my function?
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chaitanya g p
on 30 Mar 2016
Commented: Walter Roberson
on 5 Apr 2016
i do have a code, but it doesn't work quickly for 8*8. works perfectly for 32 and higher block sizes. it doesn't return the blocks either.
function y=segment1(f)
rgbImage = f;
imshow(rgbImage);
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);
drawnow;
[rows columns numberOfColorBands] = size(rgbImage);
blockSizeR =8;
blockSizeC =8;
wholeBlockRows = floor(rows / blockSizeR);
blockVectorR = [blockSizeR * ones(1, wholeBlockRows), rem(rows, blockSizeR)];
wholeBlockCols = floor(columns / blockSizeC);
blockVectorC = [blockSizeC * ones(1, wholeBlockCols), rem(columns, blockSizeC)];
if numberOfColorBands > 1
ca = mat2cell(rgbImage, blockVectorR, blockVectorC, numberOfColorBands);
else
ca = mat2cell(rgbImage, blockVectorR, blockVectorC);
end
plotIndex = 1;
numPlotsR = size(ca, 1);
numPlotsC = size(ca, 2);
for r = 1 : numPlotsR
for c = 1 : numPlotsC
fprintf('plotindex = %d, c=%d, r=%d\n', plotIndex, c, r);
subplot(numPlotsR, numPlotsC, plotIndex);
rgbBlock=ca{r,c};
imshow(rgbBlock);
[rowsB columnsB numberOfColorBandsB] = size(rgbBlock);
caption = sprintf('Block #%d of %d\n%d rows by %d columns', plotIndex, numPlotsR*numPlotsC, rowsB, columnsB);
drawnow;
plotIndex = plotIndex + 1;
end
end
end
0 Comments
Accepted Answer
Walter Roberson
on 30 Mar 2016
Your code starts
function y=segment1(f)
so it will return whatever is stored in the variable "y" by the function. But you do not store anything into y, so it cannot return the blocks. You need to store the blocks in y.
4 Comments
Walter Roberson
on 5 Apr 2016
What is your defined output type? What kind of variable do you need to return? What is it that needs to be returned?
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