Re: Zerocrossings in an image

[Etienne Grossmann]

On Sun, Apr 17, 2005 at 09:25:31PM +0200, Søren Hauberg wrote:
# Thanks, not only for the quick response, but also for the code. It 
# appears to be working very well for my needs.

I'm glad it helped.

# Can I use your code in a gpl'ed script?

Sure.
 
# /Søren
# 
# Etienne Grossmann wrote:
# >Hth
# >
# >f = 2*kron (randn(4)>0,ones(4))-1
# >
# >z0 = f<0;                 ## Negative
# >[R,C] = size(f);
# >z = zeros(R,C);
# >z(1:R-1,:) |= z0(2:R,:);  ## Grow
# >z(2:R,:) |= z0(1:R-1,:);
# >z(:,1:C-1) |= z0(:,2:C);
# >z(:,2:C) |= z0(:,1:C-1);
# >
# >z &= !z0                  ## "Positive zero-crossings"?
# >
# >
# >
# >On Sun, Apr 17, 2005 at 06:02:02PM +0200, Søren Hauberg wrote:
# ># Hi
# ># Does anybody here know a simple way to find the zerocrossings in an 
# ># image in Octave?
# ># I usually do something like this (where f is the image (or 2d function))
# ># 
# ># zerocrossings = bwmorph(f>=0, "remove");
# ># 
# ># but then I depend on bwmorph which only is octave-forge (which I don't 
# ># have at school).
# ># 
# ># Any help would be great,
# ># \Søren
# ># 
# ># 
# ># 
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# >

-- 
Etienne Grossmann ------ http://www.cs.uky.edu/~etienne



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