[Insight-users] Registration Algo

[V Narasinga Rao]

Respected Luis,

You have been an great help to me from the time I have joined ITK mailing 
list. First of all sorry for a delayed mail, as i was not well for a long 
time.

Now abt. the registration algorithm, that I have written. I wanted to get 
elastic 3D registration, so I Thought of an algorithm where i will use 
curve fitting or deformable registration on the slices and affine 
transform as a whole on the volume to get the desired results.

So far i have registered successfully CT - PET modality ( I have little 
knowledge of the instruments). I first loaded the all the slices, to 
generate the volume. Then sort of normalized teh volumes to have same 
origin. After that i registered every slices individually. The slices were 
registered with local transformations, while keeping in mind the global 
scope. Once i was able to successfully then I did global transformation to 
get the entire volume.

So far I am able to register in around 2 mins. two slices CT - PET, of 
which CT is 512 X 512 which PET is 128 X 128.

Now as for Validation, Well i am not sure the nature of application, but i 
guess i will be doing registration of uni ani multi-modal.

Please let me know weather the method that i have implemented is correct, 
Or you would like to see the output and then decide.

I will mail you the results with timming if you require so.

But before finishing off, I would like to thankyou for all the trouble 
that you have taken in replying me back, also i owe you a lot for whatever 
i have implemented for the registration code.

I joined ITK w/o any knowledge of Imaging, now I can atleast defend the 
algorithms that i have written. You have done a lot for me, and i would 
like to help you out in anywork that you want.

Once again Thanks for the help that you all people have shown to me.

Regards
Vaijanath.


On Tue, 3 Aug 2004, Luis Ibanez wrote:
>
>
> Hi Narasinga,
>
> Please do the following
>
>
>
> 1) Read the tutorial on Image Registration
>
> http://www.itk.org/CourseWare/Training/RegistrationMethodsOverview.pdf
>
>
>
> 2) Read the chapter on Image Registration from the
>   ITK Software Guide
>
>    http://www.itk.org/ItkSoftwareGuide.pdf
>
>
>
>
> The method you describe sounds pretty much like the BSpline
> deformable registration illustrated in the example
>
>
>       Insight/Examples/Registration/
>                 DeformableRegistration4.cxx
>
>
>
>
> 3) ITK is N-Dimensional. In ITK you don't do registration
>   slice by slice. Instead you use the native dimensionality
>   of the datasets.
>
>
>
>
> 4) Validation is only possible in the context of
>
>    3.1) A clinical application
>    3.2) A defined set of image modalities
>    3.3) A specific computation time allowable.
>
>   Please let us know what your clinical application
>   is, what are your image modalities and what are
>   the time demands of your clinicians.
>
>
>
>
> Regards,
>
>
>    Luis
>
>
>
>
> -----------------------
> V Narasinga Rao wrote:
>
>> Hi,
>> 
>> I have just written an algorithm which registers two images 
>> (multi-modality) in Matlab and now i want to shift it to ITK, what is the 
>> best way to do it. Also how to validate teh registration algorithm that i 
>> ave written. It's absurd question, but since i am not from medical field sp 
>> for me it's more important question.
>> 
>> 
>> I would like you all to just have a look at my algo
>> for each slice.
>> 
>> 1. Step 1. Find the region, do it for both images.
>> 2. Step 2. Enclose the region with an rectangle, by little geometry the 
>> scale and rotation parametr can be found out.
>> 3. Step 3. Once you know the scaling and rotation factor apply this to the 
>> second image.
>> 4. Step 4. Now use curve fitting to fit the curve, thus allignment will 
>> happen. 5. Step 5. One you have curve fitted now apply the original images 
>> on this binary image and now calculate teh MI to find weather the images 
>> are really registrable.
>> 
>> This entire process can take place for all the sslices in parallel way/
>> 
>> Currently it is implemented in matlab and has been giving output, ofcourse 
>> no validation regarding the registration has been done.
>> 
>> 
>> 
>> _______________________________________________
>> Insight-users mailing list
>> Insight-users at itk.org
>> http://www.itk.org/mailman/listinfo/insight-users
>> 
>
>
>
>
>