[Insight-users] Combining 3 images

[Luis Ibanez]

Hi Vera,

I'm glad to hear that you find this application interesting.

As I warned you in my previous email, the application is still
work in progress, and we anticipate to have it up and running
in a couple of days.

At that point, you will have to get it directly from CVS,
not from any of the releases.



    Regards,


        Luis



--------------------------
Vera Naumburger wrote:

> Hi Luis,
> 
> that is really interesting news :-) I´m really curious!!
> 
> I downloaded the files and could start the application. But as soon as 
> it  comes to the Eigen Analysis procedure the application breaks down 
> with the  error message:
> 
> DAMAGE: before Normal block (#0)at 0x09370B10
> 
> I'm still working with ITK version 2.0 and not with the latest version  
> 2.1. Might this be the reason?
> 
> Kind Regards,
> Vera
> 
>  Am Wed, 25 May 2005 14:57:53 -0400 schrieb Luis Ibanez  
> <luis.ibanez at kitware.com>:
> 
>>
>>
>> Hi Vera,
>>
>> Thanks for letting us know about the details of your work.
>>
>> You may find interesting to know that we recently added
>> a Curve3DExtractor application to InsightApplications.
>>
>> http://www.itk.org/cgi-bin/viewcvs.cgi/Curves3DExtractor/?root=InsightApplications 
>>
>>
>> You may want to update your CVS checkout of InsightApplications
>> and give it a try.
>>
>> There is still some work pending in this application,
>> but we anticipate it to be usable in a matter of days.
>>
>> The current version of the application computes the Hessian
>> of the input image, as well as teh Gradient. The eigenvalues
>> of the Hessian are "almost" avaialble, ... as soon as we
>> figure out some issues with memory allocation.
>>
>> We will be very interested in having your feedback on this
>> application.
>>
>>
>>      Best regards,
>>
>>
>>
>>         Luis
>>
>>
>> ----------------------------------
>> vera-naumburger at freenet.de wrote:
>>
>>> Hi Luis,
>>>  great, thanks a lot. In this special case I'm not working with 
>>> Second  Derivatives.
>>> Sorry, I wanted to combine the First Derivatives ( Gradient x, 
>>> Gradient  y and Gradient z).
>>>  Actually I´m working on one of the examples provided with ITK. I´m  
>>> trying to convert the 2D Curves Extractor into a 3D Curves 
>>> Extractor.  I´m reading CT images and let them perform all the 
>>> actions known from  the 2D Curves Extractor.
>>> I'm quite suprised that most of the converting is quite comfortable  
>>> :-)))
>>>  My question was aiming at the scalar product of the  
>>> GradientVectorImage with one of the EigenVektors. So I wasn`t sure  
>>> which filter to use instead of the JoinImageFilter to get the  
>>> GradientVectorImage. But your suggestions sound good to me.
>>> I was trying to use the GradientImageFilter on the xyz-Smothed 
>>> Image.  But result with the scalar product looks a little weird.
>>> I going to try your version.
>>>  So might be, that I have some othe questions soon :-)
>>>  Thank you a lot!
>>> Vera
>>>  ----- original Nachricht --------
>>>  Betreff: Re: [Insight-users] Combining 3 images
>>> Gesendet: Di 24 Mai 2005 17:32:07 CEST
>>> Von: "Luis Ibanez"<luis.ibanez at kitware.com>
>>>
>>>>
>>>> Hi Vera,
>>>>
>>>>
>>>>
>>>> The filter that you need is the
>>>>
>>>>
>>>> itkCompose3DVectorImageFilter
>>>> http://www.itk.org/Insight/Doxygen/html/classitk_1_1Compose3DVectorImageFilt 
>>>>
>>>> er.html
>>>>
>>>>
>>>> and/or the
>>>>
>>>>
>>>> itkCompose3DCovariantVectorImageFilter
>>>> http://www.itk.org/Insight/Doxygen/html/classitk_1_1Compose3DCovariantVector 
>>>>
>>>> ImageFilter.html
>>>>
>>>>
>>>>
>>>> Note that ITK differentiates between "Vectors" which are defined
>>>> as the difference between two positions in space, and  
>>>> "CovariantVectors"
>>>> which are defined as the orthogonal direction to a (N-1)-dimensional
>>>> subspace.  Covariant vectors represent Gradients, and Normals to
>>>> Surfaces (in 3D), while "Vectors" represent the relative position
>>>> between two points.
>>>>
>>>>
>>>> This distinction is quite important when you apply AffineTransforms
>>>> to this geometrical objects.
>>>>
>>>>
>>>>
>>>> Now that... from your email, you seems to be dealing with Second
>>>> Derivatives, in which case you are dealing with a symmetric Tensor
>>>> of Second Rank with two Covariant components. In that context you
>>>> should be careful since this object does  not behave as a Vector,
>>>> nor a CovariantVector.  In case you need it, we recently add a
>>>> Second rank symmetric tensor class to ITK.
>>>>
>>>>
>>>>
>>>> Please let us know if you have any further questions,
>>>>
>>>>
>>>>
>>>>     Thanks
>>>>
>>>>
>>>>
>>>>
>>>>       Luis
>>>>
>>>>
>>>>
>>>> ----------------------
>>>> Vera Naumburger wrote:
>>>>
>>>>
>>>>> Hi,
>>>>>
>>>>> I´m trying to combine three gradient images (xy, yz, zx), so that  
>>>>> the  output is a VectorImage. I found the JoinImageFilter for
>>>>> joining 2 images, is there something like that for 3 images, as well?
>>>>>
>>>>> Thanks,
>>>>> Vera
>>>>> _______________________________________________
>>>>> Insight-users mailing list
>>>>> Insight-users at itk.org
>>>>> http://www.itk.org/mailman/listinfo/insight-users
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>  --- original Nachricht Ende ----
>>>
>>
>>
>>
>>
> 
> 
> 
>