[Insight-users] SetHistogramMin and SetHistogramMax

[Mauro Maiorca]

Hello itk users,

I'm trying to perform otsu thresholding on a CT image. In particular I
want to threshold within the range [minValue, maxValue] with itk
3.20.0
I'm unisng itk::Statistics::ScalarImageToHistogramGenerator and
itk::OtsuMultipleThresholdsCalculator.
Unfortunately, SetHistogramMin and SetHistogramMax don't seem to work
to me! In fact, if I comment those 2 lines out:
//  scalarImageToHistogramGenerator->SetHistogramMin( minValue );
//  scalarImageToHistogramGenerator->SetHistogramMax(  maxValue );
I have the same result of when I leave those lines uncommented. I'm
actually using some code of few years ago (it was working before, I
just recompiled it today, not sure which itk version I was using at
that time).

The code I'm using is quite trivial (please, let me know if you want
me to provide more details)! Am I doing something wrong? Is it a bug?
Is this the correct mailing list to post this kind of questions? Any
hint?
here the chunk of code:

  typedef itk::Statistics::ScalarImageToHistogramGenerator<
InputImageType > ScalarImageToHistogramGeneratorType;
  typedef ScalarImageToHistogramGeneratorType::HistogramType    HistogramType;
  typedef itk::OtsuMultipleThresholdsCalculator< HistogramType >
CalculatorType;
  ScalarImageToHistogramGeneratorType::Pointer
scalarImageToHistogramGenerator =
ScalarImageToHistogramGeneratorType::New();
  CalculatorType::Pointer calculator = CalculatorType::New();

  scalarImageToHistogramGenerator->SetNumberOfBins( 128 );
  scalarImageToHistogramGenerator->SetMarginalScale( 5.0 );
  scalarImageToHistogramGenerator->SetInput( inputImage );
//  scalarImageToHistogramGenerator->SetHistogramMin( minValue ); //
<------- huh????
//  scalarImageToHistogramGenerator->SetHistogramMax( maxValue );//
<--------huh????
  scalarImageToHistogramGenerator->Compute();
  const HistogramType * histogramLow =
scalarImageToHistogramGenerator-> GetOutput();

  calculator->SetNumberOfThresholds( 3 );
  calculator->SetInputHistogram( histogramLow );
  calculator->Update();

  CalculatorType::OutputType::const_iterator itNumLow =
(calculator->GetOutput()).begin();
  HuMinimum = (int)static_cast<itk::NumericTraits<CalculatorType::MeasurementType>::PrintType>(*itNumLow);


--
Regards,
Mauro