[Insight-developers] Re: integrating the new algorithms for existing filters in ITK

[Richard Beare]

Just a note about the reconstruction filter - there is some ugliness
relating to performance experiments in that class that will need to be
removed.

Those experiments highlight a general problem about how difficult it
is to design efficient general pupose boundary conditions. In queue
based morphological algorithms a common strategy is to pad the images
with a max or min to provide a border. In itk this can be done
explicitly or implicitly - explict padding results in a quicker
filter, but higher ram usage. Optimization using face calculators is
not an option in many cases. Sacrificing a border pixel is also
possible to improve performance.

The same strategy can also be used in watershed and regional extrema filters.

It would be nice if we could establish a few conventions that support
these options consistently.



On 12/11/06, Gaetan Lehmann <gaetan.lehmann at jouy.inra.fr> wrote:
>
> Hi Luis,
>
> The new connected component and morphological reconstruction filters done
> by Richard are ready for a long time now, and work very well.
>
> The reconstruction filters are a lot faster, and much important, are a lot
> more efficient concerning memory usage.
>
> The connected component is a lot more efficient, gives consecutive labels,
> and is able to label an image containing 255 objects with a 8 bit pixel
> type - the current filter nearly always fail in that case. This last
> feature let the user decrease the memory usage, which is quite important
> for me currently.
>
> I have put those filters in my ITK tree (not in the nightly test builds
> this time :-) ) and all the tests are ok. Can I put those new algorithms
> in the cvs repository ?
>
> Thanks,
>
> Gaetan
>
>
> --
> Gaëtan Lehmann
> Biologie du Développement et de la Reproduction
> INRA de Jouy-en-Josas (France)
> tel: +33 1 34 65 29 66    fax: 01 34 65 29 09
> http://voxel.jouy.inra.fr
>