diff --git a/Code/BasicFilters/otbLogPolarResampleImageFilter.h b/Code/BasicFilters/otbLogPolarResampleImageFilter.h
index 0ffb9ac70965db64550a663c98638b6daff8ef67..b2d427c9b31d4e15f5768d20d15aa01b7e0a9d44 100644
--- a/Code/BasicFilters/otbLogPolarResampleImageFilter.h
+++ b/Code/BasicFilters/otbLogPolarResampleImageFilter.h
@@ -38,23 +38,14 @@ namespace otb
  * This function is set via SetInterpolator().  The default is
  * itk::LinearInterpolateImageFunction<InputImageType, TInterpolatorPrecisionType>, which
  *
- * Output information (spacing, size and direction) for the output
- * image should be set. This information has the normal defaults of
- * unit spacing, zero origin and identity direction. Optionally, the
- * output information can be obtained from a reference image. If the
- * reference image is provided and UseReferenceImage is On, then the
- * spacing, origin and direction of the reference image will be used.
- *
- * Since this filter produces an image which is a different size than
- * its input, it needs to override several of the methods defined
- * in ProcessObject in order to properly manage the pipeline execution model.
- * In particular, this filter overrides
- * ProcessObject::GenerateInputRequestedRegion() and
- * ProcessObject::GenerateOutputInformation().
- *
  * This filter is implemented as a multithreaded filter.  It provides a 
  * ThreadedGenerateData() method for its implementation.
  *
+ * By default the sigma value is fixed to 0.5
+ +
+ + The resampled Log-polar image dimension is a power of two for each
+ direction.
+ *
  * \ingroup GeometricTransforms
  */
 template <class TInputImage, 
diff --git a/Code/BasicFilters/otbLogPolarResampleImageFilter.txx b/Code/BasicFilters/otbLogPolarResampleImageFilter.txx
index 16febf80d31751c7b0594f6666af9c9c2ea3ecc5..d5d1f4892d15559b7bc3d47557ff70d342ca935d 100644
--- a/Code/BasicFilters/otbLogPolarResampleImageFilter.txx
+++ b/Code/BasicFilters/otbLogPolarResampleImageFilter.txx
@@ -50,9 +50,11 @@ LogPolarResampleImageFilter<TInputImage, TInterpolator>
   m_RadialStepIsConfigured  = false;
 
 
-  m_OriginIsAtCenter = true;
+  m_OriginIsAtCenter  = true;
   m_DefaultPixelValue = 0;
-  m_Interpolator = itk::LinearInterpolateImageFunction<InputImageType, CoordRepType>::New();
+  m_Sigma             = 0.5;
+  
+  m_Interpolator      = itk::LinearInterpolateImageFunction<InputImageType, CoordRepType>::New();
   
 }
 
diff --git a/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.h b/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.h
index c15bf85ef57905bbc0d15f58046210b48af97d8f..69f3d33d79b6e9773ca6ec5bc6f6ed4dd2cd4493 100644
--- a/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.h
+++ b/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.h
@@ -34,10 +34,14 @@ namespace otb
  *
  * This class implements a composite filter. It combines two filters : 
  * \begin{itemize}
- *   \item otb::LogPolarResampleImageFilter
- *   \item itk:: ...
+ *   \item otb::LogPolarResampleImageFilter : converting the input image in a
+ log-polar system coordinate
+ *   \item itk::VnlFFTRealToComplexConjugateImageFilter : applying the Forward
+ Fourier transform of the log-polar image.
  * \end{itemize}
  * 
+ * N.B.: the Fourier transform image is coded from 0.0 to 1.0
+ *
  * \ingroup ImageFunctions
  */
 
diff --git a/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.txx b/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.txx
index 3acc50a8613937a8eb1327aa9e2ca7c625d19254..39eca5a683ffae4c96b3123049bbdf8fa0f7100b 100644
--- a/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.txx
+++ b/Code/FeatureExtraction/otbForwardFourierMellinTransformImageFilter.txx
@@ -39,7 +39,6 @@ ForwardFourierMellinTransformImageFilter<TPixel, TInterpol, Dimension >
 ::GenerateData()
 {
 	m_LogPolarResample->SetInput( this->GetInput() );
-	m_LogPolarResample->Update();
  	m_FourierTransform->SetInput( m_LogPolarResample->GetOutput() );
  	m_FourierTransform->GraftOutput( this->GetOutput() );
 
@@ -69,7 +68,6 @@ ForwardFourierMellinTransformImageFilter<TPixel, TInterpol, Dimension >
 
   m_LogPolarResample->GenerateOutputInformation();
     
-  
   OutputImageRegionType    outputLargestPossibleRegion;
   outputLargestPossibleRegion.SetSize( m_LogPolarResample->GetOutput()->GetLargestPossibleRegion().GetSize() );
   outputLargestPossibleRegion.SetIndex( m_LogPolarResample->GetOutput()->GetLargestPossibleRegion().GetIndex() );