DOC: add documentation for S1ThermalNoiseLookupData

Modules/Radiometry/SARCalibration/include/otbS1ThermalNoiseLookupData.h

@@ -35,6 +35,22 @@
 namespace otb
 {
 
+/**
+ * \class S1ThermalNoiseLookupData
+ * \brief Calculate the Sentinel 1 thermal noise contribution for the given pixel
+ *
+ * This class computes the thermal noise using the noise LUTs contained in the product
+ * metadata. Range noise and azimuth noise are considered. The noise contribution is
+ * the product of the interpolated LUTs at the pixel index. Only range noise is used
+ * if the azimuth noise LUT is not available (it is the case for older products).
+ *
+ * Reference: MPC-0392 DI-MPC-TN Thermal Denoising of Products Generated by the S-1 IPF
+ *
+ * This class is templated over the input image type and the
+ * coordinate representation type (e.g. float or double ).
+ *
+ * \ingroup OTBSARCalibration
+ */
 template <class T = double>
 class S1ThermalNoiseLookupData : public itk::LightObject
 {
@@ -52,23 +68,21 @@ public:
   /** RTTI */
   itkTypeMacro(S1ThermalNoiseLookupData, itk::LightObject);
 
-
+  /** Set input metadata containing denoising LUTs */
   void SetImageKeywordlist(const ImageKeywordlist & kwl);
 
   using IndexValueType = itk::IndexValueType ;
 
+  /** Compute noise contribution for a given pixel */
   T GetValue(const IndexValueType x, const IndexValueType y);
 
-  T GetRangeNoise(const IndexValueType x, const IndexValueType y);
-
-  T GetAzimuthNoise(const IndexValueType x, const IndexValueType y);
-
 protected:
   S1ThermalNoiseLookupData() : m_FirstLineTime(0.), m_LastLineTime(0.) {m_FirstLineTime = 1.;};
   ~S1ThermalNoiseLookupData() = default;
 
 private:
 
+  /** Structure containing the azimuth noise LUT */
   struct Sentinel1AzimuthNoiseStruct
   {
     int firstAzimuthLine = 0;
@@ -80,21 +94,35 @@ private:
     std::vector<float>  vect;
   };
 
+  /** Compute range thermal noise contribution */
+  T GetRangeNoise(const IndexValueType x, const IndexValueType y);
+
+  /** Compute azimuth thermal noise contribution */
+  T GetAzimuthNoise(const IndexValueType x, const IndexValueType y);
+
   int GetRangeVectorIndex(int y) const;
 
   int GetAzimuthVectorIndex(int x, int y) const;
 
   int GetPixelIndex(int x, const std::vector<int> & vec) const;
 
+  /** First line of the S1 product */
   double m_FirstLineTime = 0.;
+
+  /** Last line of the product */
   double m_LastLineTime = 0.;
+
+  /** Duration between two lines */
   double m_LineTimeInterval = 0.;
 
   int m_NumOfLines = 0;
   int m_RangeCount = 0;
   int m_AzimuthCount = 0;
 
+  /** Range noise LUT container */
   std::vector<Sentinel1CalibrationStruct> m_RangeNoiseVectorList;
+  
+  /** Azimuth noise LUT container*/
   std::vector<Sentinel1AzimuthNoiseStruct> m_AzimuthNoiseVectorList;
 };