[Insight-users] Gradient Vector Field and Level Set

[droettger at uni-koblenz.de]

Hey Luca,

thaks for your help so far. I see how the different terms work.
I've tried th SetAdvectionImage method, but I didn't succeed.

Here are parts out of my code:

typedef itk::CovariantVector< double, 3 >  GradientPixelType;
typedef itk::Image< GradientPixelType, 3> GradientImageType;

typedef itk::GradientVectorFlowImageFilter<GradientImageType,
	GradientImageType> GVFFilterType;

GradientImageType::Pointer m_GVFField;

m_GVFField = gradientVectorFlow->GetOutput();

geodesicActiveContour->SetAdvectionImage(m_GVFField);

This is what you meant, right?

Thanks,
Diana

> Hey Diana,
>   you should set the vector image using the SetAdvectionImage method.
> The template parameter for the FeatureImageType has to be a scalar
> image of the same type of your gradient (take a look at the source
> code for the filter).
> I'm in a bit of a rush now, please get back to me if you don't
> succeed and I'll give you step by step instructions.
> Regards
>
> Luca
>
>
>
> On Nov 13, 2008, at 5:31 PM, droettger at uni-koblenz.de wrote:
>
>> Hey,
>>
>> do you mean that I should declare the feature image, the input of
>> GeodesicActiveContourLevelSetImageFilter, as the output of the
>> GradientVectorFlowImageFilter?
>>
>> I defined a GradientImageType:
>> typedef itk::CovariantVector< double, 3 >  GradientPixelType;
>> typedef itk::Image< GradientPixelType, 3> GradientImageType;
>>
>> Hence, the definition of GeodesicActiveContourLevelSetImageFilter is:
>>
>> typedef itk::GeodesicActiveContourLevelSetImageFilter<
>> InternalImageType,
>> 	GradientImageType > GeodesicActiveContourFilterType;
>>
>> Am I right? That doesn't work in my case.
>> How should I integrate the vector field?
>>
>> Thanks,
>> Diana
>>
>>
>>
>>> Hi Diana,
>>>  you should use it as the advection field in the
>>> GeodesicActiveContourLevelSetImageFilter, rather than speed.
>>> Best regards
>>>
>>> Luca
>>>
>>> 2008/11/13, droettger at uni-koblenz.de <droettger at uni-koblenz.de>:
>>>> Hi,
>>>>
>>>> I want to include the itkGradientVectorFlowImageFilter into a
>>>> level set
>>>> approach, using the ShapeDetectionLevelSetImageFilter.
>>>> The gradient diffusion, resulting out of GVF should perform an
>>>> external
>>>> force, in terms of the level set speed function.
>>>>
>>>> My question is, if I can simply use the output of
>>>> itkGradientVectorFlowImageFilter as the speed image, since it is a
>>>> vector
>>>> field, and needs a diffrent approximation than a scalar image.
>>>>
>>>>
>>>> Thanks in advance,
>>>> Diana
>>>>
>>>> _______________________________________________
>>>> Insight-users mailing list
>>>> Insight-users at itk.org
>>>> http://www.itk.org/mailman/listinfo/insight-users
>>>>
>>>
>>> --
>>> Inviato dal mio dispositivo mobile
>>>
>>> Luca Antiga, PhD
>>>  Biomedical Technologies Laboratory
>>>  Biomedical Engineering Department,
>>>  Mario Negri Institute
>>> mail: Villa Camozzi, 24020, Ranica (BG), Italy
>>> phone: +39 035 4535-381
>>> email: antiga at marionegri.it
>>> web: http://villacamozzi.marionegri.it/~luca
>>>
>>
>>
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>