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vcmohan · 22nd April 2005, 04:27

Thanks very much for the info. Infact I am looking to get hold of a fft plugin source, an inverse fft plugin source, from which i can get the coefficients to design some filters. Having a bit of aversion to all those mathematical symbols curls, matrix notations etc I can hardly understand those published software to be able to port to avisynth as a plugin for my use. I will study your source try understand.

Your plugin thru freq domain route did remove those noise freq except for a horizontal streak. Theoritically your approach is sounder than mine.Probably looks cleaner in result. But mine working in time domain works faster and does not require too much understanding of 2D fft. Very sharp edges are difficult to remove in freq domain. A short operator in time domain has a long spectrum in freq and vice versa. Please see the thread http://forum.doom9.org/showthread.php?s=&threadid=93229 . Freq domain filtering in this case may not work, I think.

I have been trying to do a notch filter in time domain but got stuck as I could not get hold of the impulse response of a notch filter. These we were using in oil exploration to remove power line interference.

I urge you to please devout some time on this plugin of yours and finish it early.

22nd April 2005, 04:27	#27 \| Link
vcmohan Registered User Join Date: Jul 2003 Location: India Posts: 916	Thanks very much for the info. Infact I am looking to get hold of a fft plugin source, an inverse fft plugin source, from which i can get the coefficients to design some filters. Having a bit of aversion to all those mathematical symbols curls, matrix notations etc I can hardly understand those published software to be able to port to avisynth as a plugin for my use. I will study your source try understand. Your plugin thru freq domain route did remove those noise freq except for a horizontal streak. Theoritically your approach is sounder than mine.Probably looks cleaner in result. But mine working in time domain works faster and does not require too much understanding of 2D fft. Very sharp edges are difficult to remove in freq domain. A short operator in time domain has a long spectrum in freq and vice versa. Please see the thread http://forum.doom9.org/showthread.php?s=&threadid=93229 . Freq domain filtering in this case may not work, I think. I have been trying to do a notch filter in time domain but got stuck as I could not get hold of the impulse response of a notch filter. These we were using in oil exploration to remove power line interference. I urge you to please devout some time on this plugin of yours and finish it early. __________________ mohan my plugins are now hosted here Last edited by vcmohan; 22nd April 2005 at 04:31.