--- a/Plugins/Samples/Common/DicomDatasetReader.cpp	Fri Dec 16 14:45:40 2016 +0100
+++ b/Plugins/Samples/Common/DicomDatasetReader.cpp	Fri Dec 16 16:22:38 2016 +0100
@@ -68,20 +68,31 @@
   }
 
 
-  DicomDatasetReader::DicomDatasetReader(IDicomDataset* dataset) :  // takes ownership
+  DicomDatasetReader::DicomDatasetReader(const IDicomDataset& dataset) :
     dataset_(dataset)
   {
-    if (dataset == NULL)
+  }
+  
+
+  std::string DicomDatasetReader::GetStringValue(const DicomPath& path,
+                                                 const std::string& defaultValue) const
+  {
+    std::string s;
+    if (dataset_.GetStringValue(s, path))
     {
-      ORTHANC_PLUGINS_THROW_EXCEPTION(ParameterOutOfRange);
+      return s;
+    }
+    else
+    {
+      return defaultValue;
     }
   }
-  
+
 
   std::string DicomDatasetReader::GetMandatoryStringValue(const DicomPath& path) const
   {
     std::string s;
-    if (dataset_->GetStringValue(s, path))
+    if (dataset_.GetStringValue(s, path))
     {
       return s;
     }
@@ -92,12 +103,22 @@
   }
 
 
-  int DicomDatasetReader::GetIntegerValue(const DicomPath& path)
+  template <typename T>
+  static T GetValueInternal(const IDicomDataset& dataset,
+                            const DicomPath& path)
   {
     try
     {
-      std::string s = StripSpaces(GetMandatoryStringValue(path));
-      return boost::lexical_cast<int>(s);
+      std::string s;
+
+      if (dataset.GetStringValue(s, path))
+      {
+        return boost::lexical_cast<T>(StripSpaces(s));
+      }
+      else
+      {
+        ORTHANC_PLUGINS_THROW_EXCEPTION(InexistentTag);
+      }
     }
     catch (boost::bad_lexical_cast&)
     {
@@ -106,10 +127,16 @@
   }
 
 
-  unsigned int DicomDatasetReader::GetUnsignedIntegerValue(const DicomPath& path)
+  int DicomDatasetReader::GetIntegerValue(const DicomPath& path) const
+  {
+    return GetValueInternal<int>(dataset_, path);
+  }
+
+
+  unsigned int DicomDatasetReader::GetUnsignedIntegerValue(const DicomPath& path) const
   {
     int value = GetIntegerValue(path);
-
+    
     if (value >= 0)
     {
       return static_cast<unsigned int>(value);
@@ -119,4 +146,16 @@
       ORTHANC_PLUGINS_THROW_EXCEPTION(ParameterOutOfRange);
     }
   }
+
+
+  float DicomDatasetReader::GetFloatValue(const DicomPath& path) const
+  {
+    return GetValueInternal<float>(dataset_, path);
+  }
+
+
+  double DicomDatasetReader::GetDoubleValue(const DicomPath& path) const
+  {
+    return GetValueInternal<double>(dataset_, path);
+  }
 }

--- a/Plugins/Samples/Common/DicomDatasetReader.h	Fri Dec 16 14:45:40 2016 +0100
+++ b/Plugins/Samples/Common/DicomDatasetReader.h	Fri Dec 16 16:22:38 2016 +0100
@@ -35,26 +35,34 @@
 #include "IDicomDataset.h"
 
 #include <memory>
+#include <vector>
 
 namespace OrthancPlugins
 {
   class DicomDatasetReader : public boost::noncopyable
   {
   private:
-    std::auto_ptr<IDicomDataset>  dataset_;
+    const IDicomDataset&  dataset_;
 
   public:
-    DicomDatasetReader(IDicomDataset* dataset);  // takes ownership
+    DicomDatasetReader(const IDicomDataset& dataset);
 
-    IDicomDataset& GetDataset() const
+    const IDicomDataset& GetDataset() const
     {
-      return *dataset_;
+      return dataset_;
     }
 
+    std::string GetStringValue(const DicomPath& path,
+                               const std::string& defaultValue) const;
+
     std::string GetMandatoryStringValue(const DicomPath& path) const;
 
-    int GetIntegerValue(const DicomPath& path);
+    int GetIntegerValue(const DicomPath& path) const;
+
+    unsigned int GetUnsignedIntegerValue(const DicomPath& path) const;
 
-    unsigned int GetUnsignedIntegerValue(const DicomPath& path);
+    float GetFloatValue(const DicomPath& path) const;
+
+    double GetDoubleValue(const DicomPath& path) const;
   };
 }

--- a/Plugins/Samples/Common/DicomTag.h	Fri Dec 16 14:45:40 2016 +0100
+++ b/Plugins/Samples/Common/DicomTag.h	Fri Dec 16 16:22:38 2016 +0100
@@ -77,19 +77,27 @@
 
 
   static const DicomTag DICOM_TAG_BITS_STORED(0x0028, 0x0101);
+  static const DicomTag DICOM_TAG_COLUMNS(0x0028, 0x0011);
   static const DicomTag DICOM_TAG_COLUMN_POSITION_IN_TOTAL_IMAGE_PIXEL_MATRIX(0x0048, 0x021e);
-  static const DicomTag DICOM_TAG_COLUMNS(0x0028, 0x0011);
+  static const DicomTag DICOM_TAG_IMAGE_ORIENTATION_PATIENT(0x0020, 0x0037);
+  static const DicomTag DICOM_TAG_IMAGE_POSITION_PATIENT(0x0020, 0x0032);
   static const DicomTag DICOM_TAG_MODALITY(0x0008, 0x0060);
   static const DicomTag DICOM_TAG_NUMBER_OF_FRAMES(0x0028, 0x0008);
   static const DicomTag DICOM_TAG_PER_FRAME_FUNCTIONAL_GROUPS_SEQUENCE(0x5200, 0x9230);
   static const DicomTag DICOM_TAG_PHOTOMETRIC_INTERPRETATION(0x0028, 0x0004);
   static const DicomTag DICOM_TAG_PIXEL_REPRESENTATION(0x0028, 0x0103);
+  static const DicomTag DICOM_TAG_PIXEL_SPACING(0x0028, 0x0030);
   static const DicomTag DICOM_TAG_PLANE_POSITION_SLIDE_SEQUENCE(0x0048, 0x021a);
-  static const DicomTag DICOM_TAG_ROW_POSITION_IN_TOTAL_IMAGE_PIXEL_MATRIX(0x0048, 0x021f);
+  static const DicomTag DICOM_TAG_RESCALE_INTERCEPT(0x0028, 0x1052);
+  static const DicomTag DICOM_TAG_RESCALE_SLOPE(0x0028, 0x1053);
   static const DicomTag DICOM_TAG_ROWS(0x0028, 0x0010);
+  static const DicomTag DICOM_TAG_ROW_POSITION_IN_TOTAL_IMAGE_PIXEL_MATRIX(0x0048, 0x021f);
+  static const DicomTag DICOM_TAG_SAMPLES_PER_PIXEL(0x0028, 0x0002);
+  static const DicomTag DICOM_TAG_SLICE_THICKNESS(0x0018, 0x0050);
   static const DicomTag DICOM_TAG_SOP_CLASS_UID(0x0008, 0x0016);
-  static const DicomTag DICOM_TAG_SAMPLES_PER_PIXEL(0x0028, 0x0002);
   static const DicomTag DICOM_TAG_TOTAL_PIXEL_MATRIX_COLUMNS(0x0048, 0x0006);
   static const DicomTag DICOM_TAG_TOTAL_PIXEL_MATRIX_ROWS(0x0048, 0x0007);
   static const DicomTag DICOM_TAG_TRANSFER_SYNTAX_UID(0x0002, 0x0010);
+  static const DicomTag DICOM_TAG_WINDOW_CENTER(0x0028, 0x1050);
+  static const DicomTag DICOM_TAG_WINDOW_WIDTH(0x0028, 0x1051);
 }