[Insight-users] problems on deformable registration 8

[Luis Ibanez]

Hi Sean,

Thanks for posting the results of your tests.

It start looking like an aliasing-effect...

but the source of the problem is problably not
directly related to the number of slices...


Moving to your second email of 07/09/09...


     Luis


------------------
Sean Lee wrote:
> Hi, Luis,
> 
> I am trying to provide more information and tested it with several other 
> numbers. Here is the results.
> 
> 29, 56, 57, 58, 59 slices: 1 iteration with a bad result.
> 
> 30 slices; 45 iterations with a good result. (of course, only half 
> volume is matched)
> 60 slices; 34 iterations with a good result.
> 
> Let me know what I can do for this issue.
> 
> Thanks.
> 
> Sean
> 
> ------------------------------------------------------------------------
> From: kevinseanlee at live.com
> To: luis.ibanez at kitware.com
> Date: Thu, 9 Jul 2009 08:22:59 -0500
> CC: insight-users at itk.org
> Subject: Re: [Insight-users] problems on deformable registration 8
> 
> Hi, Luis,
> 
> Thanks for your reply.
> 
>  > A) Did you make *any* changes to the source code
>  > of the DeformableRegistration8.cxx example ?
> I believe I did not.
> 
>  > B) How are you reading your images ?
>  > Are they DICOM files ?
>  > Are you using a Series Reader ?
> They are raw data with mhd or mha header files and I used following 
> filter to read them.
> VolumeReaderType::Pointer fixVolumeReader = VolumeReaderType::New();
> fixVolumeReader->SetFileName(fixVolumeFileName);
> fixVolumeReader->Update();
> 
>  > C) How *exactly* have you been removing slices from them.
> My original volume are 512X512. First I down-sampled them to 256X256 
> with itk::ResampleImageFilter and then
> run itk::ExtractImageFilter with following setting
> Input3DImageType::RegionType sliceRegion;
> Input3DImageType::IndexType sliceStartPoint;
> sliceStartPoint[0] = 0;
> sliceStartPoint[1] = 0;
> sliceStartPoint[2] = 0;
> Input3DImageType::SizeType NewVolumeSize;
> NewVolumeSize[0]=fixVolumeSize[0];
> NewVolumeSize[1]=fixVolumeSize[1];
> NewVolumeSize[2]=59; //or 60  !!!!! here is the way I selecting the 
> number of slices !!!!!
> sliceRegion.SetSize(NewVolumeSize);
> sliceRegion.SetIndex(sliceStartPoint);
> It is my understanding that the volume size should not affect the 
> results that much. But like what I experienced 
> earlier, changing that number could result in reaching "Convergence: 
> function tolerance reached." without a good result. 
> I hope it can always reach "Convergence: gradient tolerance reached." 
> 
> Thanks.
> 
> Sean
> 
>  > Date: Wed, 8 Jul 2009 18:08:48 -0400
>  > From: luis.ibanez at kitware.com
>  > To: kevinseanlee at live.com
>  > CC: insight-users at itk.org
>  > Subject: Re: [Insight-users] problems on deformable registration 8
>  >
>  >
>  > Hi Sean,
>  >
>  >
>  > The Exception
>  >
>  > itk::InvalidRequestedRegionError
>  >
>  >
>  > doesn't seem to be related to the registration process.
>  >
>  >
>  > A) Did you make *any* changes to the source code
>  > of the DeformableRegistration8.cxx example ?
>  >
>  >
>  > B) How are you reading your images ?
>  > Are they DICOM files ?
>  > Are you using a Series Reader ?
>  >
>  >
>  > C) How *exactly* have you been removing slices from them.
>  >
>  >
>  > D) 2Gb of RAM should be enough for registering two images of
>  > 64 slices with 256x256 pixels each.
>  >
>  >
>  >
>  >
>  > Something else is going on here....
>  >
>  >
>  >
>  > Please let us know about (A),(B) and (C)
>  >
>  >
>  >
>  > Thanks
>  >
>  >
>  >
>  > Luis
>  >
>  >
>  >
>  >
>  >