FFT ICE node

[Amaan Akram]

Hi all,

Since there's been a recent request on FFT nodes, here's one that I made a while back

www.amaanakram.com/plugins/aaFFT/1.0a/aaFFT.zip

This is a radix-2 FFT, meaning that it only works on input data sets that are powers of 2.

Sample scene included. Install the dll in workgroup application.

Windows only. If any linux users want this, please get in touch. I'll grant access to my repo.

Hope someone finds this useful.

amaan

--
Lighting Lead @ MPC, London

http://www.amaanakram.com

[Alok]

Thanks for sharing Amaan! If it not too much to ask, can you also share which paper/logic you implemented, just curious.

ALOK

GANDHI

/ chef directeur technique - lead technical director

alok....@modusfx.com

T:

450 430-0010 x225

F:

450 430-0009
www.modusfx.com

---------------------------------------------------------------------------------------------

MODUS

FX

120 Rue Turgeon,

Sainte-Therese (Quebec) CANADA J7E 3J1

Follow us on

Facebook

&

Twitter

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2012.0.2241 / Virus Database: 3162/5772 - Release Date: 04/25/13

[Amaan Akram]

Hi Alok!

This node is just an interface to the FFTW library's 1D and 2D transforms, both forward and backward. The only thing added on top is the ability to apply Centre Shifts, but only for 2D transforms for the moment

more at www.fftw.org

--
3D Artist/TD @ The Mill, London

http://www.amaanakram.com

[Alok]

Thanks for info Amaan!

ALOK

GANDHI

/ chef directeur technique - lead technical director

alok....@modusfx.com

T:

450 430-0010 x225

F:

450 430-0009
www.modusfx.com

---------------------------------------------------------------------------------------------

MODUS

FX

120 Rue Turgeon,

Sainte-Therese (Quebec) CANADA J7E 3J1

Follow us on

Facebook

&

Twitter

[Jens Lindgren]

Thank you so much Amaan!

Will start working on my effect this weekend.

 

/Jens

--

Jens Lindgren

--------------------------

Lead Technical Director

Magoo 3D Studios

[Andy Moorer]

Whoa, cool! Thanks for sharing this out!

Sent from my iPad

[olivier jeannel]

Ahem,
Can someone enlight me on this ? Or, is there somewhere a picture, or "something" that explain how a Fourier Transform applies in real (3d) world. http://www.fftw.org is a bit far from my low understing.
Everybody seems to be super happy with that FFT node, but I just don't understand the use.
Just curious.

Thank's

[Eric Turman]

The internet is full of information...but its not always comprehensible. For example: wikipedia brings up as nearly a technical explanation (in a concise form ;P ) as the fftw.org

FFT is used with periodic waveform interaction to tease out values --decompose into sine components. (I hope that I'm not mangling the meaning by trying to cram it down into one sentence) This link does a better job at explaining it:

http://www.earlevel.com/main/2002/08/31/a-gentle-introduction-to-the-fft/

There are so many uses for FFT. It is a valuable (arguably critical) tool for all sorts of signal processing ranging from noise filtering to 3D tracking. But perhaps a  more immediate and practical application of it in the 3D world is its facilitation of the deformation calculation of Amaan's aaocean polygonal surface http://www.amaanakram.com/?page_id=131

I hope this helps :)

Cheers,

-=Eric

[olivier jeannel]

Helps a bit, thank's ;)

[Amaan Akram]

Some practical applications

Jos Stam's classic fluid dynamics paper that uses fourier transforms

http://www.dgp.toronto.edu/people/stam/reality/Research/pdf/jgt01.pdf

FFTs applied to images

http://www.cs.unm.edu/~brayer/vision/fourier.html

People create noise textures in FFTs, or analyze noise via FFTs

There's also the classic spectrum visualization that is also dependent on FFTs

Jens Lindgren has a very interesting application of FFTs too. Jens?

 The classic 'low-cut' or high-pass filters in photoshop are also applications of ffts

[Andy Moorer]

I got this book at siggraph, it's now in digital form. http://www.dspguide.com/ch24/6.htm

Very helpful and idea-provoking. :)

[Jens Lindgren]

My first project with Amaans FFT nodes is going to be boat wakes: http://upload.wikimedia.org/wikipedia/commons/thumb/c/c0/Fjord.surface.wave.boat.jpeg/1024px-Fjord.surface.wave.boat.jpeg

I was planning to develop it during the weekend but I didn't have time, but I will start on it today.

 

/Jens

 

[Grahame Fuller]

Here's an example of using a Fourier transform to remove moiré patterns: http://www.reindeergraphics.com/tutorial/part04.html

You can think of the Fourier transform as just a different way of looking at your data that makes some operations easier. It's similar to, e.g., using polar coordinates to make it easier to paint out seams in panoramas.

gray

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Jens Lindgren
Sent: Monday, April 29, 2013 02:05 AM
To: soft...@listproc.autodesk.com
Subject: Re: FFT ICE node

My first project with Amaans FFT nodes is going to be boat wakes: http://upload.wikimedia.org/wikipedia/commons/thumb/c/c0/Fjord.surface.wave.boat.jpeg/1024px-Fjord.surface.wave.boat.jpeg
I was planning to develop it during the weekend but I didn't have time, but I will start on it today.

/Jens

On Mon, Apr 29, 2013 at 12:24 AM, Andy Moorer <andym...@gmail.com<mailto:andym...@gmail.com>> wrote:
I got this book at siggraph, it's now in digital form. http://www.dspguide.com/ch24/6.htm

Very helpful and idea-provoking. :)

On Apr 28, 2013, at 12:34 PM, Amaan Akram <xsi...@warpedspace.org<mailto:xsi...@warpedspace.org>> wrote:
Some practical applications

Jos Stam's classic fluid dynamics paper that uses fourier transforms

http://www.dgp.toronto.edu/people/stam/reality/Research/pdf/jgt01.pdf

FFTs applied to images
http://www.cs.unm.edu/~brayer/vision/fourier.html

People create noise textures in FFTs, or analyze noise via FFTs

There's also the classic spectrum visualization that is also dependent on FFTs

Jens Lindgren has a very interesting application of FFTs too. Jens?

The classic 'low-cut' or high-pass filters in photoshop are also applications of ffts

On 28 April 2013 15:59, olivier jeannel <olivier...@noos.fr<mailto:olivier...@noos.fr>> wrote:
Helps a bit, thank's ;)

Le 28/04/2013 14:47, Eric Turman a écrit :

The internet is full of information...but its not always comprehensible. For example: wikipedia brings up as nearly a technical explanation (in a concise form ;P ) as the fftw.org<http://fftw.org>

FFT is used with periodic waveform interaction to tease out values --decompose into sine components. (I hope that I'm not mangling the meaning by trying to cram it down into one sentence) This link does a better job at explaining it:
http://www.earlevel.com/main/2002/08/31/a-gentle-introduction-to-the-fft/

There are so many uses for FFT. It is a valuable (arguably critical) tool for all sorts of signal processing ranging from noise filtering to 3D tracking. But perhaps a more immediate and practical application of it in the 3D world is its facilitation of the deformation calculation of Amaan's aaocean polygonal surface http://www.amaanakram.com/?page_id=131

I hope this helps :)

Cheers,
-=Eric




--
3D Artist/TD @ The Mill, London
http://www.amaanakram.com



--
Jens Lindgren
--------------------------
Lead Technical Director

Magoo 3D Studios<http://www.magoo3dstudios.com/>