How to perform 2-D DFT via 1-D DFT
10 views (last 30 days)
Show older comments
Take the 1-D DFT of one image, first row-wise 1-D DFT and followed by column-wise 1-D DFT to create the resulting F1(u,v) .
0 Comments
Accepted Answer
Wayne King
on 28 Jun 2012
It actually doesn't matter, but you can do this
X = randn(8,8);
Y = fft2(X);
% ok let's first take the DFT along the rows
rowdft = fft(X,[],2);
% now take it along the columns
coldft = fft(rowdft,[],1);
max(max(abs(coldft-Y)))
See the maximum difference in absolute value is only on the order of 10^(-15)
1 Comment
P
on 30 Jan 2013
Can you perform this same function without using fft2 or fft? that is doing the 2d dft first along the row and then along the col without using fft2 or fft.
More Answers (1)
Wayne King
on 22 Jun 2012
Here is an example that shows you how to do it
X = randn(8,8);
fft2(X)
% now use fft
fft(fft(X).').'
See Also
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!