[Insight-developers] NRRD Image Format (and tensor estimation thereafter?)

[Vincent A. Magnotta]

Karthik,

It has been my experience that loading a NRRD formated image, all of the 
images are stored in a single vector image. Gordon will have to weigh in 
on the NAMIC "standard".

Vince

Karthik Krishnan wrote:

> Done. You have the option of specifying the gradients in a a single 
> VectorImage or as several itk::Image
>
> One question:
> Doesn't the he nrrd format for DWI images store the B0 and the 'n' 
> gradient images in one nrrd image or are they in two seperate images ? 
> Is that the NAMIC defacto ?
>
> bye
> karthik
>
> Gordon Kindlmann wrote:
>
>> hello,
>>
>>> Reference + DWI Gradient images  ---->  
>>> DiffusionTensor3DReconstructionImageFilter  -----> itk::Image<  
>>> DiffusionTensor3D< TScalar >, 3 >
>>>
>>> To this image you can apply one of the may tensor filters like:
>>>
>>> TensorFractionalAnisotropyImageFilter,
>>> TensorRelativeAnisotropyImageFilter,
>>> Hessian3DToVesselnessMeasureImageFilter,
>>> SymmetricEigenAnalysisImageFilter,
>>
>>
>>
>> Vincent, is this helpful for your purposes, and do the different  
>> types of image make sense?
>>
>>> I presume your question was "Can the DWI Gradient images" be a  
>>> itk::VectorImage.
>>> Not with the way the filter is written right now, It expects 'n'  
>>> itk::Images as input, but its very easy to make it expect an  
>>> itk::VectorImage as input. If you want, I can change that or add  
>>> another filter.
>>>
>>> Would you rather have it expect a VectorImage ?
>>
>>
>>
>> Well, if its simply a matter of asking, then yes! :)
>>
>> I think it would be good to have the Tensor estimation filter take a  
>> VectorImage, since this would allow one to write code that loads an  
>> arbitrary DWI protocol, represented in the NAMIC Nrrd format, and  
>> then estimate tensors and do other processing.
>>
>> Gordon
>>
>>
>>
>


-- 
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