Re: Leeres FFT Image erzeugen

Posted by Christophe CHAMOT on Dec 15, 2006; 8:51am
URL: http://imagej.273.s1.nabble.com/Leeres-FFT-Image-erzeugen-tp3700819p3700821.html

Johannes Schindelin a écrit :

> Hi,
>
> On Wed, 13 Dec 2006, Maja Temerinac wrote:
>  
>
> Since I _am_ fluent in German, and this is an English-only mailing list, I
> will just translate here:
>
> "My problem: I have to FFT images, and need to create just one by taking
> the maximum of both FFT images. I did that by using 'Process->Image
> Calculator...' with the 'MAX' operation. When I tried to apply the inverse
> transformation ('Process->FFT->InverseFFT') it failed with 'Frequency
> domain image required', though. Help?"
>
> Dear Maja, as Kriss pointed out, you can use the image calculator without
> creating a new image, keeping the information FHT needs.
>
> Alternatively, I _think_ that renaming the resulting ("MAX") image to "FHT
> of result" and _then_ applying the inverse FFT should work (I get that
> impression from reading the source; unfortunately I do not have a means to
> test right now).
>
> Hth,
> Dscho
>  

Hi Johannes,

And thanks for the translation ;-)

Just as a new clue about what Maja said, I tried to duplicate an
foreward FFT image (no more angular informations when you pass the mouse
on the duplicated image) then rename with "FHT of blabla..." and you
were right. The inverse FFT can be performed but the result is a noisy
32bits image (original was a 8bits Lena).

Any idea ?

Thanks in advance.

Kriss



--
Christophe CHAMOT
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