How does imresize 'Antialiasing' work?

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I want to know how the imresize function works when I set 'Antialiasing' option to true.
There are so many methods to make Antialiasing.
The imresize function says that when I set 'Antialiasing' option true, the imresize function will do antialiasing.
So I want to know exactly how imresize function does 'Antialiasing'.
  2 Comments
Star Strider
Star Strider on 29 Jul 2021
It could be similar to the antialiasing in the Signal Processing Toolbox resample function, that uses a FIR filter to remove spurious high frequencies (greater than the original signal Nyquist frequency) that are created in the interpolation process.
I have not looked at the code of either one in any detail (assuming that is even possible).

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Accepted Answer

DGM
DGM on 29 Jul 2021
Edited: DGM on 29 Jul 2021
If I recall from digging through the code before, it mentions using a modified kernel to simultaneously interpolate and antialias. I don't know which methods are relevant to that chunk of code, but you're free to look at the code yourself.
EDIT:
I can't really point out line numbers since it changes between versions. Circa R2015b, most everything is still in imresize.m, which is in the IPT directory. Look for a function called contributions().
By R2019b, the parts of imresize() are spread across several files in $MLROOT/toolbox/matlab/images/+matlab/+images/+internal/+resize/
Look in that directory for contributions.m and see if you can make sense of it.

More Answers (1)

Image Analyst
Image Analyst on 29 Jul 2021
It probably blurs the image slightly.

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