[Insight-users] VectorImage Registration Metric

[Luis Ibanez]

Hi Lisa,

Please look at the file:

NAMICSandBox/VectorImageRegistrationMethod/Source/
                    itkVectorMeanSquaresImageToImageMetric.txx

and the lines that have "FIXME" messages as comments.


These are the lines where a change from "Scalar", to "Vector"
computation remains to be introduced.

For example, the "gradient", used to be a Vector in the
computation of a Metric for a Scalar image, but when
doing that computation for  a Vector image, the gradient
must be a Matrix, which is composed of the gradients
of each individual component of the vector image.


Please let us know if you see any problems with
the suggested implementation,


      Thanks


            Luis


------------------------------------------------------------------------------------------
On Fri, Feb 5, 2010 at 2:30 PM, Lisa Tang <lisat at sfu.ca> wrote:
> Hi Luis,
>
> You mentioned that the version in NAMIC sandbox need "massaging":
>
> "The Gradient of the vector image must be computed as a matrix
> and multiplied with the Transform jacobian in order to produce
> another matrix, that then will be collapsed into a gradient
> vector. (to be done)"
>
> However, I find that both the Sandbox's itkVectorMeanSquaresImageToImageMetric and itkMeanSquaresImageToImageMetric calculate the metric's derivative similarly, and so are the calculations of the gradient image in itkVectormageToImageMetric.
>
> Could you please clarify which class were you referring to that requires the above change?
>
> Thanks in advance,
> Lisa
>
>
>
>
> ----- "Luis Ibanez" <luis.ibanez at kitware.com> wrote:
>
>> From: "Luis Ibanez" <luis.ibanez at kitware.com>
>> To: "Ghassan Hamarneh" <hamarneh at cs.sfu.ca>
>> Cc: "Lisa Tang" <lisat at sfu.ca>
>> Sent: Friday, 5 February, 2010 07:04:30 GMT -08:00 US/Canada Pacific
>> Subject: Re: VectorImage Registration Metric
>>
>> Hi Ghassan,
>>
>> I haven't seen much activity in this project for a while,
>> but sometimes research groups make progress without
>> necessarily sharing their day-to-day updates with the
>> community.
>>
>> I would suggest to bring up the topic to the ITK users
>> and developers list.
>>
>> I will be happy to ask the question in the lists if you
>> prefer me to do it.
>>
>>
>>      Regards,
>>
>>
>>           Luis
>>
>>
>>
>> ---------------------------------------------------------
>> On Fri, Feb 5, 2010 at 12:55 AM, Ghassan Hamarneh <hamarneh at cs.sfu.ca>
>> wrote:
>> >
>> > Hello Luis
>> >
>> > Hope all is well!
>> >
>> > I came across this thread:
>>  http://www.cmake.org/pipermail/insight-users/2008-May/025746.html
>> >
>> > We were thinking of contributing something similar (vector valued
>> image registration) to the insight journal as was developed for our
>> paper:
>> >
>> > [ SMRFI: Shape Matching via ] Registration of Vector-Valued Feature
>> Images
>> > http://www.cs.sfu.ca/~hamarneh/ecopy/cvpr2008.pdf
>> >
>> > Before investing more time on this, we appreciate if you could let
>> us know the status of this effort, is any one working on this, etc?
>> >
>> > Thanks,
>> >
>> > /Ghassan
>> >
>> >
>> >
>> >
>> >
>