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Re: Label_region and Erosion [message #13415 is a reply to message #13283]

Wed, 04 November 1998 00:00

lbryanNOSPAM
Messages: 21
Registered: July 1998

Junior Member

On 4 Nov 1998 12:10:34 GMT, Struan Gray <struan.gray@sljus.lu.se>
wrote:

> when playing with masked filtering I have found that it
> is easiest to filter a copy of the whole dataset and then use the mask
> to pick out the parts you actually wanted and insert them into the
> original data. For my sorts of data the time penalty incurred by
> filtering everything is more than compensated for by the generality of
> the procedure (multiple, oddly shaped, reentrant regions are handled
> transparently) and it's programming simplicity. You also have a
> nicely behaved default behaviour for how boundary values are dealt
> with when using filters of various widths.
>
>
> Struan

Ok, I think this may work...

This is my data. Where the 0's represent pixel values which have a
mean of 0 and deviation of about 10. And the +'s have a mean of 300
and a deviation of about 30. And the size of the array is actually
about 400x400. Plus both surfaces have a few nasty noise spikes that
are significantly higher or lower than described.

00000000000000000000
000000+000++00000000
0000+++00+++++000000
0000++++++++00000000
00000+0++++++0+00000
00000000++0++++00000
000000000000++++0000
00000000000000+00000
00000000000000000000
00000000000000000000

If I can get dilate to work on my greyscale image can expand the size
of the island by the width of my filter, filter the entire image, then
select the original region, I should be able to avoid all edge
effects. (Up to this point filtering causes all my surfaces to turn
into upside down bowls.) Now if I can just get dilate to work on a
greyscale image. Thanks for the ideas!

Lisa B.

Arete Associates
Tucson, Arizona
lbryan@arete-az.com

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[Message index]

		Label_region and Erosion By: lbryanNOSPAM on Tue, 03 November 1998 00:00
		Re: Label_region and Erosion By: Struan Gray on Fri, 06 November 1998 00:00
		Re: Label_region and Erosion By: David Foster on Thu, 05 November 1998 00:00
		Re: Label_region and Erosion By: Alex Schuster on Thu, 05 November 1998 00:00
		Re: Label_region and Erosion By: Struan Gray on Wed, 04 November 1998 00:00
		Re: Label_region and Erosion By: lbryanNOSPAM on Wed, 04 November 1998 00:00
		Re: Label_region and Erosion By: Struan Gray on Wed, 04 November 1998 00:00

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