[Insight-users] Does "InPlace" filters really work "In Place"?

[Yulia.Arzhaeva at csiro.au]

Hi,

Indeed, there is no problem with running an "InPlace" filter with
provided example images. However, there are no examples of tif images in
the Examples\Data folder, and the runtime error I described in an
earlier email happens when I run a ThresholdImageFilter test with some
tif images. 

I found out that the crash has nothing to do with filtering but with
writing an output image in a file. Although, it's not possible to catch
it as an exception - the error happens because a null pointer is
addressed within one of the functions called inside TIFFImageIO::Read().


I've done a bit of debugging and that is what I've found. In a pipeline,
that connects a reader with a filter with a writer, calling
writer->Update() causes an update of a reader, because, with
filter->InPlaceOn(), the filter input gets released. For tif images,
TIFFImageIO::Read() is called, which uses m_InternalImage that is
supposed to have a non-null pointer m_Image to an allocated piece of
memory. m_InternalImage is filled in TIFFImageIO::CanReadFile(), which
is not called the second time, as a part of writer->Update() procedure.
As a result, m_InternalImage->m_Image points to NULL, and causes the
runtime error when addressed in TIFFImageIO::Read().  If one includes
filter->GetOutput()->DisconnectPipeline() before calling
writer->Update(), no error occurs because no input image update occurs. 

I guess, there might be an error in handling tif images. Could anyone
please comment?
Thanks.
Yulia
 

----------
Bill Lorensen wrote:

Yulia,

The example works fine for me when I add filter->InPlaceOn(). Are you
running the example data or your own?

Replace the first filter-<Update(); with

  try
    {
    filter->Update();
    }
  catch (itk::ExceptionObject &ex)
    {
    std::cout << ex;
    return EXIT_FAILURE;
    }

and see if you get more information.

Actually, place a try/catch around each ->Update() just in case the
problem is with reading or writing.

Bill

On Fri, Jul 25, 2008 at 11:07 AM,  <Yulia.Arzhaeva at csiro.au> wrote:
> Hello,
>
> I have just started using ITK, so I might have overlooked something..
>
> I have tried to use ThresholdImageFilter with "InPlace" feature ON,
i.e. I called filter->InPlaceOn() before calling filter->Update(). As a
result, I got a runtime error. I played with an example code, so it can
be reproducible.
>
> If you take an example code ThresholdImageFilter.cxx from the
..\Examples\Filtering folder , leave just one filter update instead of
three updates, for simplicity, and insert filter->InPlaceOn(), would you
get a runtime error as well?
>
> Could you explain me what's wrong, either with my way to set InPlace
feature, or with using such a filter "In Place" at all?
>
> Thanks,
> Yulia
> _______________________________________________
> Insight-users mailing list
> Insight-users at itk.org
> http://www.itk.org/mailman/listinfo/insight-users
>
_______________________________________________
Insight-users mailing list
Insight-users at itk.org
http://www.itk.org/mailman/listinfo/insight-users