Spatial Frequency

Supposing i have a 1-D or 2-D data...how do i get the spatial frequencies from the FFT expression ( FFT results in a spectrum plotted against sample count)..

Answer 1

[Wayne King]

Hi, See this tutorial (which ImageAnalyst provided in an earlier post):

http://sharp.bu.edu/~slehar/fourier/fourier.html

[Palguna Gopireddy]

I cant open this link.. Please post it again.

Answer 2

[David Young]

From this demo:

The Fourier component corresponding to index j has j-1 cycles within the length of the original data.

If there are N data points, the component corresponding to index j has the same frequency as the component corresponding to index N-j+2.

Answer 3

[Rick Rosson]

Please check this related question:

fftshift of an image

HTH.