MATLAB: Imresize is blurring the image!

imresize

Hello

I have a 128×128 matrix and I want to scale it down to 32×32. MATLAB's algorithm "imresize" seems to involve a smoothing filter. My original image has sharp gradients across pixel edges which will remain pixel edges in the new image, but these gradients are being lost by a seemingly overenthusiastic filtering step.

Is there a simple way of simply saying "see this 4×4 box? well that's going to be a single pixel in the new image, so take the mean of these 16 values and ignore everything else around it"?

I could try to code this manually but I'm checking that there isn't a quicker alternative, since it'll take me a while.

Regards, Michael

Best Answer

 I = imresize(I, [32 32], 'nearest');

Related Solutions

MATLAB: IMWRITE followed by IMREAD Changes Pixel Values

I tried this, and I realized that ISEQUAL compares a DOUBLE and UINT8, which quite obviously does not return true.

 p = rand(150,200,3);
 imwrite(p,'test.png');
 pnew = imread('test.png');
 isequal(p,pnew)

if you really want to check equality,

 isequal(im2uint8(p),pnew)

is the way to go.

MATLAB: Matlab adds additional margin to an image!

Amin - from your code

ax = uiaxes(fig,'position',[78 120 240 240]);
imshow('Support1.png','parent',ax);
ax = uiaxes(fig,'position',[220 120 240 240]);

isn't the first axes created at x-coordinate 78 with a width of 240? So that would mean that 78+240=318...but the second axes is created at x-coordinate 220 which is less than 318 which leads to overlap amongst the two axes. Maybe you need to create the second axes at least at x-coordinate 318 so that there is no overlap between the two.

Best Answer

Related Solutions

MATLAB: IMWRITE followed by IMREAD Changes Pixel Values

MATLAB: Matlab adds additional margin to an image!

Related Question