Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!mimsy!oddjob!gargoyle!ihnp4!homxb!mhuxt!mhuxm!mhuxo!ulysses!sfmag!sfsup!grk From: grk@sfsup.UUCP (G.R.Kuntz) Newsgroups: comp.lang.c Subject: Re: fast fourier transform Message-ID: <1646@sfsup.UUCP> Date: Fri, 17-Jul-87 09:42:51 EDT Article-I.D.: sfsup.1646 Posted: Fri Jul 17 09:42:51 1987 Date-Received: Sat, 18-Jul-87 18:44:56 EDT References: <1065@bloom-beacon.MIT.EDU> <3251@cit-vax.Caltech.Edu> Organization: AT&T-IS, Summit N.J. USA Lines: 18 Several years ago I saw an article in BYTE about a 2-dimensional FFT for a Commodore PET (yeah, I bet you thought there were only good for controlling toasters :-) ). This allowed the user to enter a picture using a simple up-down-left-right editor, and then do a 2-d FFT on it, destroy part of the result with the editor, and then do a reverse FFT and GET MOST OF THE PICTURE BACK. It flipped me out, even though I knew that a hologram is really just an analog fourier transform or something like an FT. I was wondering if the 2-d FFT is done by performing a regular FFT on each row, and then the same on each column. Anyone know? (Wrong group for FFT discussions, but if someone has one in C, we could try the picture stuff.) Cheers, Ralph -- G. Ralph Kuntz N2HBN UUCP: {ihnp4,allegra}!attunix!grk ARPA: rutgers.rutgers.edu!pisc2b!grk PACKET: N2HBN @ NN2Z