Talk:Mexican hat wavelet

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Renaming to Ricker Wavelet[edit]

Is it necessary to name this as the Mexican Hat Wavelet? It's more recognizable name is the Ricker Wavelet so perhaps this should be the official name. Chris Engelsma 18:04, 20 October 2011 (UTC)

I agree with this. Ricker Wavelet is a much more common name. I have not heard Mexican Hat Wavelet in any place other than here. All publications I have read call it Ricker. 129.7.231.237 (talk) 06:52, 12 April 2012 (UTC)
This function is referred to as the Mexican hat function in the image processing and computer vision communities. In these areas, this is an established terminology. I have also seen a number of mathematicians using this terminology. Therefore, a redirect from Richer Wavelet may be more appropriate. I have never heard of Ricker wavelet before this occasion now, however. Tpl (talk) 09:38, 14 April 2012 (UTC)

normalizing term[edit]

Is the normalizing term correct there? i have coded this in matlab: excit_function=sprintf('(1-((t-%e).^2/%e.^2)).*exp(-(t-%e).^2/(2*%e.^2))',5*ex_sigma,ex_sigma,5*ex_sigma,ex_sigma); t=0:dt:sim_time; excit=eval(excit_function); which is without the normalizing term and it correctly evaluates so that peak is +1 and not something like +10^27 —Preceding unsigned comment added by 188.220.32.144 (talk) 20:59, 25 February 2010 (UTC)


Lanczos resampling[edit]

This looks a lot like the kernel of Lanczos resampling. Is this just a superficial relationship? —Ben FrantzDale (talk) 21:32, 31 December 2007 (UTC) Yes, it's just resemblance, there's no relationship. crisluengo (talk) 07:50, 15 September 2009 (UTC)

normalizing term, second post[edit]

> I've changed the coefficient in front of the equation to be the mathematical result of what it says it should be, ie. the second derivative of a normalized Gaussian distribution.

It shouldn't be the second derivative of a normalized Gaussian distribution. It should be a wavelet, normalized by ordinary wavelet normalization rules:

(see Wavelet)

Is second image 3D or 2D?[edit]

This is 1-dimensional wavelet. It depends on one variable :

This is 2-dimensional wavelet. It depends on two variables: :

The image itself is 3d, but what it depicts is a 2d wavelet. — Preceding unsigned comment added by Eloquent2013 (talkcontribs) 09:06, 24 December 2015 (UTC)