[Insight-users] Re: MutualInformationImageToImageMetric

[Luis Ibanez]

Hi Malempati,

It is very unlikely that the source of the problem
is the size in Kilobytes of your images.


If you have an observer and the error message
appears before the observer reports on the first
iteration, then you can remove the Optimizer
as a suspect, and instead focus on the most
likely reasons;


   1) A poor initialization of the Transform.

or

   2) Invalid values of origin & spacing in the
      fixed and moving images.


Questions:

1) What is the size of your images in pixels ?
2) What is the pixel spacing of each image ?
3) What is the origin of the images ?


You can get all this information by calling

    reader->GetOutput()->Print( std::cout )



Also:


4) What transform are you using ?
5) How are you initializing the Transform ?



   Regards,



      Luis



-------------------------------------------
deepa_malempati at rediff.com wrote:
> Hi,
> Luis,thanks for u'r reply.
> i have used the observer,but not even single iteration is getting performed.Would it be due to the size variation of the images.The sizes of the fixed image is 21KB and that of moving image is 6 KB.
> waiting for u'r reply,
> Thanking u,
> MALEMPATI.
> Luis Ibanez wrote:
> 
>>
>>
>>Hi Malempati:
>>
>>
>>1) Read the ITK Software Guide
>>
>>      http://www.itk.org/ItkSoftwareGuide.pdf
>>
>>    in particular the Image Registration chapter.
>>
>>
>>2) Make sure that your images have valid values
>>    of image origin and image spacing
>>
>>3) Make sure that you initialize the Transform
>>    parameters
>>
>>4) Add an observer to the Optimizer, and print
>>    out the values of the metric and transform
>>    parameters at every iteration.
>>
>>5) Identify how many iterations you manage to
>>    run before you get the error message.
>>
>>
>>
>>The error means that the Fixed and Moving images
>>have such small overlap that the registration
>>process can't continue.
>>
>>The problem may be caused by:
>>
>>a) incorrect image information
>>b) bad initialization
>>c) poor choices in the optimizer parameters
>>
>>
>>
>>   Regards
>>
>>
>>      Luis
>>
>>
>>
>>-------------------
>>MALEMPATI wrote:
>>
>>>Hi, 
>>>all.how to get rid of this error given below. 
>>>
>>> itk::ERROR: MutualInformationImageToImageMetric(012C9D90): All the 
>>>sampled point mapped to outside of the moving image
>>
>>_______________________________________________
>>Insight-users mailing list
>>Insight-users at itk.org
>>http://www.itk.org/mailman/listinfo/insight-users
>>
>>
> 
> Quoted from: 
> http://www.nabble.com/MutualInformationImageToImageMetric-tf3762435.html#a10652461
> 
>