[Insight-developers] GDCM IO and metadata copying

[Peter Cech]

Hi,

when GDCM IO is copying metadata from image, it does not distinguish
between simple tags and sequence of tags. As a consequence, it segfaults
when reading DICOM file with sequence tag. You can grab such a file from
http://www.vision.ee.ethz.ch/~pcech/bugreports/ITK-20041108/

Attached patch contains a workaround. It will skip all tag sequences.  
I suspect that the proper fix would require more than just copy all tags
from sequence, so I better leave it to someone with better knowledge of
DICOM format.

Regards,

Peter Cech
-------------- next part --------------
--- Insight/Code/IO/itkGDCMImageIO.cxx	2004-11-03 10:57:29.000000000 +0100
+++ Insight-modified/Code/IO/itkGDCMImageIO.cxx	2004-11-06 10:45:26.040344296 +0100
@@ -293,10 +293,14 @@
     // Do not copy field from private (unknown) dictionary.
     // In the longer term we might want to (but we need the Private dictionary
     // from manufacturer)
+    if (tag->second->GetVR().find("SQ") == 0) {
+      // skip sequence, otherwise following cast will crash
+      continue;  
+    }
 #if GDCM_MAJOR_VERSION == 0 && GDCM_MINOR_VERSION <= 5
-    std::string temp = ((gdcmValEntry*)(tag->second))->GetValue();
+    std::string temp = synamic_cast<gdcmValEntry*>(tag->second)->GetValue();
 #else
-    std::string temp = ((gdcm::ValEntry*)(tag->second))->GetValue();
+    std::string temp = dynamic_cast<gdcm::ValEntry*>(tag->second)->GetValue();
 #endif
     if( tag->second->GetName() != "unkn" 
      && temp.find( "gdcm::NotLoaded" ) != 0