comp.lang.idl-pvwave archive: archive » Re: 2D Savitzky-Golay derivative filter?

Home » Public Forums » archive » Re: 2D Savitzky-Golay derivative filter?

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: 2D Savitzky-Golay derivative filter? [message #83093 is a reply to message #83092]

Sun, 03 February 2013 11:08

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

David Grier writes:

> I would like to use Savitzky-Golay filters to calculate gradients of images.
> Before I roll my own code to calculate the filter coefficients, I was wondering
> if anyone here already had working routines that they would be willing to share.
>
> IDL's built-in SAVGOL routine only computes one-dimensional filters, and I need
> two-dimensional filters. Erik Rosolowsky's SAVGOL2D computes two-dimensional
> smoothing filters, but not two-dimensional derivative filters.
>
> Alternatively, is there an equivalently good IDL way to compute image gradients?
> A useful replacement would offer the noise rejection of Savitzky-Golay without
> suppressing peaks the way that SMOOTH() does.

The Sobel and Roberts functions are both 2D gradient or derivative
filters, or you can just roll your own and do some kind of Laplacian
filter:

http://www.idlcoyote.com/ip_tips/sharpen.html

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.idlcoyote.com/
Sepore ma de ni thue. ("Perhaps thou speakest truth.")

Report message to a moderator

[Message index]

		Re: 2D Savitzky-Golay derivative filter? By: dg86 on Sun, 03 February 2013 13:37
		Re: 2D Savitzky-Golay derivative filter? By: David Fanning on Sun, 03 February 2013 11:08
		Re: 2D Savitzky-Golay derivative filter? By: dg86 on Wed, 06 February 2013 18:19

Previous Topic:	Re: Interupting a running procedure using Widget event interupts.
Next Topic:	MAKE_RT strange behaviour

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 17:54:09 PDT 2025

Total time taken to generate the page: 0.00208 seconds