From eae9a01c2edd9f615a78dc64a8e7731d09e815a1 Mon Sep 17 00:00:00 2001
From: malaterre <malaterre>
Date: Fri, 12 Nov 2004 21:33:46 +0000
Subject: [PATCH] BUG: Apply patch proposed by Peter Cech (ITK user), to handle
 some Philips NTSCAN where some private tag were being flip to Big endian for
 no reason (the rest of the file is in little endian).

---
 src/gdcmDocument.cxx | 34 ++++++++++++++++++++++++++++++++--
 src/gdcmDocument.h   |  5 +++--
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/src/gdcmDocument.cxx b/src/gdcmDocument.cxx
index df8bd9fc..e406a1c4 100644
--- a/src/gdcmDocument.cxx
+++ b/src/gdcmDocument.cxx
@@ -3,8 +3,8 @@
   Program:   gdcm
   Module:    $RCSfile: gdcmDocument.cxx,v $
   Language:  C++
-  Date:      $Date: 2004/11/10 18:27:23 $
-  Version:   $Revision: 1.121 $
+  Date:      $Date: 2004/11/12 21:33:46 $
+  Version:   $Revision: 1.122 $
                                                                                 
   Copyright (c) CREATIS (Centre de Recherche et d'Applications en Traitement de
   l'Image). All rights reserved. See Doc/License.txt or
@@ -2637,6 +2637,35 @@ void Document::SetMaxSizePrintEntry(long newSize)
 
 
 
+/**
+ * \brief   Handle broken private tag from Philips NTSCAN
+ *          where the endianess is being switch to BigEndian for no
+ *          apparent reason
+ * @return  no return
+ */
+void Document::HandleBrokenEndian(uint16_t group, uint16_t elem)
+{
+   // Endian reversion. Some files contain groups of tags with reversed endianess.
+   static int reversedEndian = 0;
+   // try to fix endian switching in the middle of headers
+   if ((group == 0xfeff) && (elem == 0x00e0))
+   {
+     // start endian swap mark for group found
+     reversedEndian++;
+     SwitchSwapToBigEndian();
+     // fix the tag
+     group = 0xfffe;
+     elem = 0xe000;
+   } 
+   else if ((group == 0xfffe) && (elem == 0xe00d) && reversedEndian) 
+   {
+     // end of reversed endian group
+     reversedEndian--;
+     SwitchSwapToBigEndian();
+   }
+
+}
+
 /**
  * \brief   Read the next tag but WITHOUT loading it's value
  *          (read the 'Group Number', the 'Element Number',
@@ -2662,6 +2691,7 @@ DocEntry* Document::ReadNextDocEntry()
       return 0;
    }
 
+   HandleBrokenEndian(group, elem);
    DocEntry *newEntry = NewDocEntryByNumber(group, elem);
    FindDocEntryVR(newEntry);
 
diff --git a/src/gdcmDocument.h b/src/gdcmDocument.h
index 628f8bca..0324a946 100644
--- a/src/gdcmDocument.h
+++ b/src/gdcmDocument.h
@@ -3,8 +3,8 @@
   Program:   gdcm
   Module:    $RCSfile: gdcmDocument.h,v $
   Language:  C++
-  Date:      $Date: 2004/10/28 03:10:57 $
-  Version:   $Revision: 1.56 $
+  Date:      $Date: 2004/11/12 21:33:46 $
+  Version:   $Revision: 1.57 $
  
   Copyright (c) CREATIS (Centre de Recherche et d'Applications en Traitement de
   l'Image). All rights reserved. See Doc/License.txt or
@@ -261,6 +261,7 @@ private:
    void BuildFlatHashTableRecurse( TagDocEntryHT& builtHT,
                                    DocEntrySet* set );
 
+   void HandleBrokenEndian(uint16_t group, uint16_t elem);
 public:
 // Accessors:
    /// Accessor to \ref PrintLevel
-- 
2.48.1