[Insight-users] MutualInformationImageToImageMetric: Lack of Transform Initialization

[MALEMPATI]

Hi Luis,
I could not follow the ITK Documentation about the attributes that should be
passed to these 2 methods,could u let me know them including syntax.
And where could i get the different DataSets for Registration.I need them
very urgently,as i have only 2 datasets.
Thank u in advance,
Malempati

Luis Ibanez wrote:
> 
> 
> Hi Malempati,
> 
> When you report the "size" of an image, you
> should indicated in terms of the number of
> pixels along every dimension.
> 
> For example:  1024 x 768 pixels.
> 
> 
> The report:
> 
>             Size: 42496
> 
> is not very useful.
> 
> 
> ---
> 
> If you are *not initializing* the Transform,
> then that's the source of your registration
> problem.
> 
> 
> At a minimum, you should initialize the Transform
> in such a way that the centers of both images will
> overlap.
> 
> For a description on how to do this
> please read the ITK Software Guide
> 
>     http://www.itk.org/ItkSoftwareGuide.pdf
> 
> in particular the "Image Registration" chapter.
> 
> For instruction on how to initialize transforms
> see, Section 8.6.1., pdf-pages 382-382,
> 
> As you will see, the computation involves the number
> of pixels of the image along every dimension, the
> pixel spacing and the origin.
> 
> 
> 
>     Regards,
> 
> 
>         Luis
> 
> 
> 
> ---------------------------------------
> deepa_malempati at rediff.com wrote:
>> Hi,
>> Luis.
>> The details of images are given below:
>> 1:Fixedimage                           2:MovingImage
>>   a.Size: 42496                            Size: 39277
>>   b.Spacing: [1.2, 1.01562]         Spacing: [1, 1]
>>   c.  Origin: [0, 0]                          Origin: [0, 0]
>> And i'm using the Translation Transform.It is not Initialized with any
>> values in the code.
>> 
>> Luis Ibanez wrote:
>> 
>>>
>>>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
>>>>
>>>>
>>>
>>>_______________________________________________
>>>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#a10664017
>> 
>> 
> _______________________________________________
> Insight-users mailing list
> Insight-users at itk.org
> http://www.itk.org/mailman/listinfo/insight-users
> 
> 

-- 
View this message in context: http://www.nabble.com/Re%3A-MutualInformationImageToImageMetric%3A-Lack-of-Transform-Initialization-tf3781966.html#a10733768
Sent from the ITK - Users mailing list archive at Nabble.com.