FFT produces a Discrete Fast Fourier Transform of a data set. The
FFT will be the same size as the original data set and will represent only
the positive frequencies, hence low frequencies will be to the top/left
of the resulting image.
FFT has a drag and drop button, so its results can be fed into other
applications, for example, it's often useful to feed FFT output into a
Histogram
in order to adjust the color table.
Controls
Buttons
The Histogram button fires up a Histogram,
already linked into FFT. [Not implemented yet.]
Menu
The Transform menu gives six options; they are what the application computes.
The default computation is a one-dimensional FFT along each row of the
data. Alternatively, one can select 1D FFTs along each column or a 2D FFT
(which is simply an FFT along the rows, then columns). All the corresponding
inverse transforms can be chosen as well.
Applications to Connect to This Application
Any Data Object may be connected via the
"drag 'n drop" button to this application. Histogram
is very useful in order to change the color table to make the details of
the FFT visible. A slider will control the slice
of the original data set used for the computation.
Applications to Connect This Application to
None.
Tricks and Gotchas
Please tell us!
WebWinds Home
/ Oct 5, 2001
