Path: utzoo!attcan!uunet!clyde.concordia.ca!news-server.csri.toronto.edu!utgpu!watserv1!ria!lri.uwo.ca From: root@lri.uwo.ca (0000) Newsgroups: comp.dsp Subject: Hartley Transfor Message-ID: <9008071249.AA11662@lri.uwo.ca> Date: 7 Aug 90 12:49:35 GMT Sender: LRuucp@ria.ccs.uwo.ca Lines: 25 To: comp.dsp@ria.ccs.uwo.ca > >Does anyone know or have pointers to the literature or code about how >to do multidimensional Hartley transforms (i.e., is it obvious that a For another source of info use Bracewells "The Hartley Transform" Oxford University Press 1986 ISBN 0-19-503969-6 There are programs in the back, but the in-place radix 2 program is wrong (In my humble opinion). >2D HT is the same as 2 1D HT's, or do I need some correction), and what >the correlation and convolution theorems look like for multidimensional >Hartley transforms? NO! two 1D HT not equal to 1 2D HT. ie if the input function is Hermitian symmetric such that the FT of the function is real, the real and imaginary components must be moved around. ie if the input is a(x,y) + ib(x,y), i denotes imag part, the input to the HT is: c(x,y) = a(x,y) - b(-x,y) NB I cant remember offhand which component has the negative sign in b(x,y). > Hope this helps.