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Fizick · 23rd November 2004, 19:28

I make experimental very slow FFT denoiser.

FFT3DFilter - 3D Frequency Domain filter-denoiser

FFT3DFilter uses Fast Fourier Transform method for frequency selecting an removing.

The algorithm is based on the 3D IIR/3D Frequency Domain Filter from:
MOTION PICTURE RESTORATION. by Anil Christopher Kokaram. Ph.D. Thesis. May 1993.
http://www.mee.tcd.ie/~ack/papers/a4ackphd.ps.gz

It is a spatial-temporal (3D) filter, and works as follows:

1) get 3 frames (previous, current, and next);
2) divide every frame to small overlapped blocks;
3) get frequency spectrum by windowed forward 3D FFT transform of every block of 3 frames;
4) reduce weak frequencies (with small power spectral density) by optimal Wiener filter with some given noise value;
5) make inverse 3D FFT transform of cleaned spectrum for every block;
6) do windowed summation of cleaned overlapped blocks to output frame.

Features:
1. Works only in YV12 color format.
2. Directly works with progressive clips. For interlaced sources, probably you must use SeparateFields etc.
3. Tested with Avisynth 2.55.
4. Uses fast external FFTW library version 3 (http://www.fftw.org)
as Windows binary DLL (compiled with gcc under MinGW by Alessio Massaro),
which support for threads and have AMD K7 (3dNow!) support in addition to SSE/SSE2.
It may be downloaded from ftp://ftp.fftw.org/pub/fftw/fftw3win32mingw.zip
You MUST put FFTW3.DLL file from this package to some directory in path (for example, C:\WINNT).
Filter will NOT work without it!
5. It is slooow!

EDIT: New versions are not so slow now

and have some other features and restrictions. See updated doc included with filter!
I do not want to change this first post by historical reasons

23rd November 2004, 19:28	#1 \| Link
Fizick AviSynth plugger Join Date: Nov 2003 Location: Russia Posts: 2,183	New very slow FFT denoiser I make experimental very slow FFT denoiser. FFT3DFilter - 3D Frequency Domain filter-denoiser FFT3DFilter uses Fast Fourier Transform method for frequency selecting an removing. The algorithm is based on the 3D IIR/3D Frequency Domain Filter from: MOTION PICTURE RESTORATION. by Anil Christopher Kokaram. Ph.D. Thesis. May 1993. http://www.mee.tcd.ie/~ack/papers/a4ackphd.ps.gz It is a spatial-temporal (3D) filter, and works as follows: 1) get 3 frames (previous, current, and next); 2) divide every frame to small overlapped blocks; 3) get frequency spectrum by windowed forward 3D FFT transform of every block of 3 frames; 4) reduce weak frequencies (with small power spectral density) by optimal Wiener filter with some given noise value; 5) make inverse 3D FFT transform of cleaned spectrum for every block; 6) do windowed summation of cleaned overlapped blocks to output frame. Features: 1. Works only in YV12 color format. 2. Directly works with progressive clips. For interlaced sources, probably you must use SeparateFields etc. 3. Tested with Avisynth 2.55. 4. Uses fast external FFTW library version 3 (http://www.fftw.org) as Windows binary DLL (compiled with gcc under MinGW by Alessio Massaro), which support for threads and have AMD K7 (3dNow!) support in addition to SSE/SSE2. It may be downloaded from ftp://ftp.fftw.org/pub/fftw/fftw3win32mingw.zip You MUST put FFTW3.DLL file from this package to some directory in path (for example, C:\WINNT). Filter will NOT work without it! 5. It is slooow! EDIT: New versions are not so slow now and have some other features and restrictions. See updated doc included with filter! I do not want to change this first post by historical reasons __________________ My Avisynth plugins are now at http://avisynth.org.ru and mirror at http://avisynth.nl/users/fizick I usually do not provide a technical support in private messages. Last edited by Fizick; 22nd November 2005 at 22:49.