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From: ImageAnalyst <imageanalyst@mailinator.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Image Region -> perimeter sample
Date: Sun, 11 May 2008 09:45:35 -0700 (PDT)
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On May 10, 4:42=A0pm, "Ahmad " <ahmad.hu...@gmail.com> wrote:
> Hi there,
>
> Given a binary image of a single connected object, what is
> the quickest way to find a sample of pixels on its
> edge/perimeter. By a sample of pixels I do not mean all
> pixels on the perimeter, but just a sample of fixed number
> of pixels, where each pixel is separated from the other by
> some margin. (I also have the Image processing toolbox)
>
> Regards,
----------------------------------------------------------------------------=
--------
Ahmad:
What is it about bwboundary that you don't know how to deal with?
This gives you the boundaries of objects.  You could then take a
"sample of fixed number of pixels" from that just by taking the first
N pixels, or using rand to generate indexes to extract or lots of
other methods.  What are you really after when you say your want just
a sample of the boundaries rather than all of them.  What good would
that be?
Regards,
ImageAnalyst