[Insight-users] Level set: Time vs. Iteration

[Sah Rayman]

My question is, is there a way to specify the time, T,
instead of number of iterations, for my
SegmentationLevelSetImageFilter?

Here is my understanding of how L.S. in ITK works: 
1. for each iteration, it calculates deltaT according
to CFL. ( BTW, is it 0.25 for 2D and 0.125 for 3D?)
2. phi_new = phi_old + deltaT * deltaPhi;
...

I can easily specify the number of iterations by:
SegmentationLevelSetImageFilter::SetNumberOfIterations().

However, in my case, the time parameter makes more
sense, e.g. I know the zero level set goes about 4
pixels after 4 time units if the propogation is 1
everywhere.

So is it possible that I tell ITK to go 1.5 time unit,
and then ITK automatically run 1.5/0.25=6 iterations?

Or, if the above is unavailable, is there a way I can
know how many time has elapsed ( \sum deltaT) after N
iterations?

I am using ITK 1.8 if that makes any difference.


		
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