[Insight-users] Mattes MI: "Too many samples map outside..."

[Xabier Artaechevarria Artieda]

Just another point: the error arised at the 174th iteration. If there  
was problem with the pixel endiant, should not it arise at the first  
iteration?

-- 
Xabier Artaechevarria
Cancer Imaging Laboratory
Centre for Applied Medical Research
www.cima.es



Christoph Palm <christoph.palm at web.de> ha escrito:

> But differences due to endian format is very easy to recognize,
> if you look at your images, isn't it? Additionally, the result
> of registration might be crap, but the position of the spatial samples
> (without using Padding values and masks) as well as their number should
> be independent from the endian format.
>
> -- Christoph
>
>
>
> On Tue, 2007-02-13 at 21:50 -0500, Minjie Wu wrote:
>> Hi,
>>
>> I met the same error when using Mattes MI: "Too many samples map   
>> outside...".
>>
>> In my case, I resaved both analyze images (moving image and target
>> image) using the same the software: ImageJ. Then the error
>> disappeared.
>>
>> I think the error might due to the endianness of the input images. One
>> image is with big endian format, the other one is little endian
>> format.
>>
>> You may want to try to resave the images using same software, and see
>> if this remove the error message.
>>
>> Good luck,
>> Minjie
>>
>>
>>
>>
>>
>>
>> On 2/13/07, Xabier Artaechevarria Artieda <xabiarta at unav.es> wrote:
>> > I agree, that is odd. In fact, the images are exactly the same size,
>> > and they have been registered with an affine transform previously.
>> >
>> >
>> >
>> >
>> > Karthik Krishnan <karthik.krishnan at kitware.com> ha escrito:
>> >
>> > > That's odd.
>> > >
>> > > Is the moving image a lot smaller than the fixed image ?   
>> Samples are taken
>> > > from the fixed image. If the moving image is a lot smaller, that could
>> > > explain their mapping outside the moving image region.
>> > >
>> > > -karthik
>> > >
>> > >
>> > > On 2/12/07, Xabier Artaechevarria Artieda <xabiarta at unav.es> wrote:
>> > >>
>> > >> Hi Karthik,
>> > >> Thanks for your answer.
>> > >> I just set the maximum number of iterations to 174 and applied the
>> > >> resulting transform to the moving image. Comparing it to the fixed
>> > >> image, the overlapped seemed good.
>> > >> I tried changing the number of spatial samples (from 1/10 to 1/9) and
>> > >> now the registration is working fine. I must admit I do not really
>> > >> know why.
>> > >> Regards,
>> > >> Xabi
>> > >>
>> > >>
>> > >>
>> > >>
>> > >> Karthik Krishnan <karthik.krishnan at kitware.com> ha escrito:
>> > >>
>> > >>> On 2/9/07, Xabier Artaechevarria Artieda <xabiarta at unav.es> wrote:
>> > >>>>
>> > >>>> Hallo Christoph,
>> > >>>> Thanks for the answer.
>> > >>>> I checked after 174 iterations and the overlap seems in fact good,
>> > >>>
>> > >>>
>> > >>> How did you ascertain the fact that the overlap is good ? (I   
>> presume you
>> > >>> checked the transform, but I don' tsee it printed in the log). There
>> > >> must be
>> > >>> a significant drift in teh transform from teh initial position to the
>> > >>> position after 174 iterations to prompt this error.
>> > >>>
>> > >>> DId you try resampling with the transform and overlaying the images to
>> > >> make
>> > >>> sure that the transforms are headed in the right direction ?
>> > >>>
>> > >>> and
>> > >>>> it is considerably better than at the first iteration. Do you think I
>> > >>>> could solve the problem by using a higher number of spatial samples?
>> > >>>> Now I am using one tenth of the total voxels.
>> > >>>
>> > >>>
>> > >>> 1/10th for MI is plenty.
>> > >>>
>> > >>>
>
>
>
>



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