[Insight-developers] wrapped filters types

[Luis Ibanez]

Hi Gaetan,

We all agree with your request of having all the ITK filters
available at the wrapped layer.

Unfortunately this is a technical challenge where we face
the trade-off of:


       1) Time required for building wrapping
       2) Size of the libraries
       3) Convenience of having all filters available


The option that you mention for wrapping all filters for the same
InputImage and OutputImage type is interesting, however it doesn't
go too far once you start considering details, for example, what
would you do with filters that produce vector images, what would
you do with the watershed filter that produces unsigned long labels,
What would you do with filters that require float/double images, or
those that produce signed images like the signed distance danielsson
filter.


The interesting question with wrapping is :


       At any given time,
       how many classes is a developer actually using ?


  1)    10% of the toolkit ?
  2)     1% of the toolkit ?



There are about 700 classes in ITK. Few pipelines use more than
20 different types of filters. This situation is what lead us to
a "user-driven" selection of the classes to wrap. In other words
we only wrap the classes (and instantiations) that are of interest
for the users.

You simply need to post to the users list the names and types
of the filters that you consider should be wrapped. You could also
enter this as a request on the phpBugtracker.

Asking for wrapping 'everything' is a well intentioned proposition
but unfortunately is not a realistic one.

Much more useful is your final statement when you specifically
mention the filters that you are really missing right now. In
particular some types for the Rescale (I assume you meant the
RescaleIntensityImageFilter) and the labels filter.

Could you please be more specific regarding the particular pixel
types that you are needing to be wrapped ?

With that list we will be able to add the corresponding wrapping
files to the system.


Please let us know,


    Thanks


       Luis


------------------------
Gaetan Lehmann wrote:

> 
> Hi,
> 
> One of the biggest problem when I try to use itk wrappers, is that not 
> all  filters are wrapped.
> Itk wrapper user can rebuild the wrapper to add the filter he need, but  
> clearly, if someone use the wrapper, he don't want to have to rebuild 
> the  wrappers.
> ITK should have a script to be sure that all filters are wrapped.
> 
> The other big problem is that it's sometime impossible to build a 
> pipeline  with the same type, because all the types are not wrapped. I 
> know that  wrapped all types for all filters would produce a too big 
> library. A  possible solution would be to make all filters (except cast 
> filter)  avaible only with the same input and output type. If user wants 
> to change  type in is pipeline, he must use a cast filter. This would 
> make possible  to wrap all filters with all types.
> Some filters (like rescale or label filters) should also be avaible 
> with  more types.
> 
> Comments ?
> 
> Gaetan.
>