[Insight-developers] Modifying MaskImageFilter to work on VectorImage

Tue Apr 12 04:12:32 EDT 2011

Le 12 avr. 11 à 07:33, Cory Quammen a écrit :

> Hi Gaëtan,
>
> Thank you for your thoughtful comments.
>
> 2011/4/11 Gaëtan Lehmann <gaetan.lehmann at jouy.inra.fr>:
>>
>> Hi Cory,
>>
>> I think this code would fail if the mask filter is run a second  
>> time with a
>> vector image with a different number of components.
>> There should be a check for the number of components in
>> BeforeThreadedGenerateData().
>
> Yes, it would be good to check that the number of components in the
> OutsideValue matches the number in the image, throwing an exception if
> the number of components doesn't match.
>
>> The initialization of the default value of OutsideValue is quite
>> problematic, as it can be done only when the number of components  
>> is known.
>
> Agreed!
>
>> A better option would be to have a way to say "I want to use the  
>> default
>> value" - in that case the value can be generated in
>> BeforeThreadedGenerateData() and would fit the vector the filter is
>> currently working on - or "I want to use that value" and then it is  
>> the
>> responsibility of the user to provide the right number of components.
>>
>> One way to implement that is to use a 3rd input for the filter  
>> which would
>> be of type
>>
>>  SimpleDataObjectDecorator< PixelType >
>>
>> and to not provide a default value by default - just keep the 3rd  
>> input as
>> NULL. If there is no 3rd input, then the default value of  
>> OutsideValue can
>> be generated in BeforeThreadedGenerateData(). If there is a 3rd  
>> input, then
>> just use the value provided.
>
> While your suggestion sounds reasonable, the same behavior can also be
> achieved using the current ITK norm of setting filter constants via a
> method. All it would take would be to examine the OutsideValue to see
> if it is zero length or if it consists of all zeros, and if so, infer
> that the user wants to use the default value with the correct number
> of components. To get back to the "default" value, all the user would
> have to do is set the OutsideValue to some vector of zeros or a
> zero-length vector. Does that seem reasonable?
>
>> An additional benefit of that approach: the OutsideValue can be  
>> provided
>> through the pipeline, which is not the case currently.
>
> I think that your notion of treating filter constants as inputs to the
> pipeline is very interesting and has merit, but I'll defer to more
> experienced developers to determine if that is where ITK should be
> heading.
>

Hi Cory,

You're right, this is not the purpose of this change.
Your proposition to use the default value for a zero length vector  
seems quite good to me.

Gaëtan

> Thanks,
> Cory
>
>>
>>
>> Le 11 avr. 11 à 07:30, Cory Quammen a écrit :
>>
>>> David and Luis,
>>>
>>> I have posted a potential solution on github.
>>>
>>>
>>> https://github.com/cquammen/ITK/commit/a92bcc79f267d79f48abb7358881c4b2323ae01d
>>>
>>> I will post it to gerrit if you don't see any showstoppers.
>>>
>>> Thanks,
>>> Cory
>>>
>>> On Sun, Apr 10, 2011 at 5:50 PM, Luis Ibanez <luis.ibanez at kitware.com 
>>> >
>>> wrote:
>>>>
>>>> Hi David,
>>>>
>>>> We have been discussing this problem with Julien Malik from the
>>>> Orfeo Toolbox team.
>>>>
>>>> In summary, there is a function in the NumericTraits that is  
>>>> intended
>>>> to deal with management of size in containers of variable size
>>>> such as the VariableLengthVector and the std::vector.
>>>>
>>>> Regarding your questions, please see below.
>>>>
>>>> On Thu, Apr 7, 2011 at 7:50 PM, David Doria  
>>>> <daviddoria at gmail.com> wrote:
>>>>>
>>>>> We have been having some discussion on the best way to allow
>>>>> MaskImageFilter
>>>>> to work on VectorImage (with pixels of type  
>>>>> VariableLengthVector) . The
>>>>> problem is that the length of a VariableLengthVector is not  
>>>>> defined at
>>>>> compile time. This means that in the MaskInput functor, the
>>>>> member m_OutsideValue cannot be initialized.
>>>>>
>>>>> Brad has identified two problems,
>>>>>
>>>>> 1) How do we initialized the member variable in the functor?
>>>>>
>>>>
>>>> We usually add "Set" methods to the functor,
>>>> the add "Set" methods to the Filter itself,
>>>> and they simply call the "Set" methods of the functor.
>>>>
>>>>> This seems to be the main issue I'm not sure how to address.
>>>>>
>>>>> 2) When do we detect the size of the vector image, and use  
>>>>> reasonable
>>>>> defaults?
>>>>>
>>>>
>>>>
>>>> At run time,
>>>> by asking them for their "GetNumberOfComponents()
>>>> from the vector image.
>>>>
>>>> Reasonable default (otherwise) is "1".
>>>>
>>>>> We think this could be done in BeforeThreadedGenerateData.
>>>>>
>>>>
>>>> Yes, that's a good place.
>>>>
>>>> The GenerateInputInformation() or
>>>> GenerateOutputInformation() may
>>>> be good places as well.
>>>>
>>>>
>>>>> The complete conversation is here:
>>>>>
>>>>> http://review.source.kitware.com/#change,1338
>>>>> Any thoughts are welcome!
>>>>> Thanks,
>>>>>
>>>>> David
>>>>>
>>>>> _______________________________________________
>>>>> Powered by www.kitware.com
>>>>>
>>>>> Visit other Kitware open-source projects at
>>>>> http://www.kitware.com/opensource/opensource.html
>>>>>
>>>>> Kitware offers ITK Training Courses, for more information visit:
>>>>> http://kitware.com/products/protraining.html
>>>>>
>>>>> Please keep messages on-topic and check the ITK FAQ at:
>>>>> http://www.itk.org/Wiki/ITK_FAQ
>>>>>
>>>>> Follow this link to subscribe/unsubscribe:
>>>>> http://www.itk.org/mailman/listinfo/insight-developers
>>>>>
>>>>>
>>>> _______________________________________________
>>>> Powered by www.kitware.com
>>>>
>>>> Visit other Kitware open-source projects at
>>>> http://www.kitware.com/opensource/opensource.html
>>>>
>>>> Kitware offers ITK Training Courses, for more information visit:
>>>> http://kitware.com/products/protraining.html
>>>>
>>>> Please keep messages on-topic and check the ITK FAQ at:
>>>> http://www.itk.org/Wiki/ITK_FAQ
>>>>
>>>> Follow this link to subscribe/unsubscribe:
>>>> http://www.itk.org/mailman/listinfo/insight-developers
>>>>
>>>
>>>
>>>
>>> --
>>> Cory Quammen
>>> Computer Integrated Systems for Microscopy and Manipulation (CISMM)
>>> Department of Computer Science
>>> University of North Carolina at Chapel Hill
>>> http://www.cs.unc.edu/~cquammen
>>> _______________________________________________
>>> Powered by www.kitware.com
>>>
>>> Visit other Kitware open-source projects at
>>> http://www.kitware.com/opensource/opensource.html
>>>
>>> Kitware offers ITK Training Courses, for more information visit:
>>> http://kitware.com/products/protraining.html
>>>
>>> Please keep messages on-topic and check the ITK FAQ at:
>>> http://www.itk.org/Wiki/ITK_FAQ
>>>
>>> Follow this link to subscribe/unsubscribe:
>>> http://www.itk.org/mailman/listinfo/insight-developers
>>
>> --
>> 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  http://www.itk.org
>> http://www.mandriva.org  http://www.bepo.fr
>>
>>
>
>
>
> -- 
> Cory Quammen
> Computer Integrated Systems for Microscopy and Manipulation (CISMM)
> Department of Computer Science
> University of North Carolina at Chapel Hill
> http://www.cs.unc.edu/~cquammen

-- 
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  http://www.itk.org
http://www.mandriva.org  http://www.bepo.fr

-------------- next part --------------
A non-text attachment was scrubbed...
Name: PGP.sig
Type: application/pgp-signature
Size: 203 bytes
Desc: Ceci est une signature ?lectronique PGP
URL: <http://www.itk.org/mailman/private/insight-developers/attachments/20110412/ac536233/attachment.pgp>