comp.lang.idl-pvwave archive: archive » Re: Raster to Vector outlines- Classification Image

Home » Public Forums » archive » Re: Raster to Vector outlines- Classification Image

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

Re: Raster to Vector outlines- Classification Image [message #69530 is a reply to message #69529]

Sat, 23 January 2010 07:07

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

Robin Wilson writes:

> I've got a classification image consisting of various polygons, each of
> a different value (integers, from 1 to about 59,000!). I'd like to
> display all of the boundaries of these polygons on the image, either in
> an EVF file or just as an ROI with pixels for each of the boundaries so
> I can overlay it on the image.
>
> I've tried using RTV_DOIT, but that extracts each boundary to a separate
> EVF file. I've written a routine to stitch together all these EVF files,
> but the creation of 1000 of the EVF files using RTV_DOIT takes quite a
> while - and the 59,000 polygons I have is only for a small image!
>
> Does anyone know of any better way to do this? It can be using an ENVI
> procedure or a built-in IDL function, or a simple way to write some IDL
> code to do this.

I've done some "blob" analysis before and I've discovered
there are fast ways and there are slow ways. The fast ways,
naturally, involve a histogram. You may find some ideas
about how to solve your problem by reading some of these
articles. I'd probably start with this one:

http://www.dfanning.com/ip_tips/blobanalysis.html

Cheers,

David

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

Report message to a moderator

[Message index]

		Re: Raster to Vector outlines- Classification Image By: Mort Canty on Sat, 23 January 2010 11:05
		Re: Raster to Vector outlines- Classification Image By: David Fanning on Sat, 23 January 2010 07:07

Previous Topic:	Raster to Vector outlines- Classification Image
Next Topic:	PAYPAL payment wholesale BRAND shoes,clothing,watch,handbag,jean,ugg boot,t-shirt,jersey,eyeglass,belt,wallet and so on

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Oct 10 10:33:54 PDT 2025

Total time taken to generate the page: 1.11854 seconds