On Wed, Jun 17, 2009 at 04:37:12AM -0700, Travis Collier wrote: > Digging through the list archive, I see mention of norxcorr2 in devel. > Vikram never seemed to get a replay as to the status... and I am in > want of it too. > > I'm assuming that there is some clever application of FFTs which does > the computation relatively efficiently. If not, someone please tell > me. > I've already got the "compute the corrcoeff at each lag" method > implemented as a C mex file. > -- > Travis
Would "xcorr2" (in the signal package) do the same job for you ? As a first step, you might need to subtract the mean from the arguments. Also, you might find that the "coeff" does not normalise the result correctly -- so you might need to divide the "biassed" result by the rms of each of the argument images. And yes, multiplying FFTs (and then inverse FFT) is much much faster than the brute force method. -- Peter ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Octave-dev mailing list Octave-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/octave-dev
