[Insight-users] ExtractImageFilter

[Luis Ibanez]

Hi Puja,

The ExtractImageFilter shouldn't be changing
the intensity values of the extracted pixels.
It is supposed to simply copy their values
into a smaller image.

What kind of image are you processing ?

What method are you using for computing
the intensity range ?

(e.g. you could use the MinimumMaximumImageCalculator.)

BTW an example on the use of the ExtractImageFilter
is available under:

Insight/Examples/IO/ImageReadExtractWrite.cxx

and is described in the SoftwareGuide on the
section:

      "Reading and Writing Images"

You can experiment with it by passing 2D images
and providing the index and size in the command
line. It reads and writes PNG, DICOM, VTK, and
MetaImage formats.


Please let us know some more details of what
you are doing.


   Thanks


      Luis


----------------------------------
Puja Malik wrote:

> Hello,
> I'm having trouble using the itk ExtractImageFilter.
> 
> In my implementation, I use an image of size {512,512,30}.  The interger 
> range in this image is from 0 to 272.  When I extract a region size of 
> the same size as the image, I get back the correct image.  However, if I 
> set my index as {0,0,0} and extract a region size of {511, 511, 30}, 
> then I get the correct image back, however the interger range is now 
> from 0 to 4161 and the image appears much dimmer.  It seems that the 
> smaller I make the region to be extracted, the larger the resulting 
> image's interger range is.
> 
> Perhaps I'm not understanding the functionality of the 
> ExtractImageFilter properly.  Does anyone have any idea how I could fix 
> this?
> 
> Thanks,
> Puja
>  
> 
> -- 
> ---------------------------------------
> Puja Malik
> Surgical Instruments Group
> MEM Research Center for Orthopaedic Surgery
> Institute for Surgical Technology and Biomechanics 
> University of Bern
> Murtenstrasse 35, P.O. Box 8354
> 3010 Bern, Switzerland
> Phone: +41-31-632-8730
> Fax: +41-31-632-4951
> Email: Puja.Malik@MEMcenter.unibe.ch
> http://www.MEMcenter.unibe.ch
> ---------------------------------------
> 
>