Re: perimeter of a blob

[davidf(at)dfanning.com (David Fanning)]

Richard Adams (r.j.adams@bath.ac.uk) writes:

> Dear Ben, if you just need the indices and not the indices in order around
> the perimeter then you could use an imaging method like this:

You know, I think this whole thing has to be a lot
easier than this.

Ben is getting the data from Label_Region, which returns
regions labeled with a single value (or "color", as I
prefer to think of them). Why not just use the CONTOUR
command to draw a contour around the region, then use
the information in all those PATH_**** keywords to
find the perimeter? With clever programming (I'll 
leave this part to Ben) you can find all the holes
in the data, etc.

I think I might even have a piece of code around here
where I did this once. If I get some time (unlikely 
today) I'll have a look around.

Cheers,

David

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David Fanning, Ph.D.
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