--- a/Framework/Inputs/DicomPyramid.cpp	Mon Apr 07 18:08:06 2025 +0200
+++ b/Framework/Inputs/DicomPyramid.cpp	Mon Apr 07 18:41:34 2025 +0200
@@ -24,6 +24,7 @@
 #include "../PrecompiledHeadersWSI.h"
 #include "DicomPyramid.h"
 
+#include "../ImageToolbox.h"
 #include "../DicomToolbox.h"
 
 #include <Compatibility.h>
@@ -191,6 +192,8 @@
 
     for (size_t i = 0; i < instances_.size(); i++)
     {
+      assert(instances_[i] != NULL);
+
       if (i == 0 ||
           instances_[i - 1]->GetTotalWidth() != instances_[i]->GetTotalWidth())
       {
@@ -201,6 +204,8 @@
         assert(levels_.back() != NULL);
         levels_.back()->AddInstance(*instances_[i]);
       }
+
+      instances_[i]->SetLevel(levels_.size() - 1);
     }
   }
 
@@ -276,7 +281,30 @@
   bool DicomPyramid::LookupImagedVolumeSize(double& width,
                                             double& height) const
   {
-    CheckLevel(0);
-    return levels_[0]->LookupImagedVolumeSize(width, height, seriesId_);
+    bool found = false;
+
+    for (size_t i = 0; i < instances_.size(); i++)
+    {
+      assert(instances_[i] != NULL);
+
+      if (instances_[i]->IsLevel(0) == 0 &&  // Only consider the finest level
+          instances_[i]->HasImagedVolumeSize())
+      {
+        if (!found)
+        {
+          found = true;
+          width = instances_[i]->GetImagedVolumeWidth();
+          height = instances_[i]->GetImagedVolumeHeight();
+        }
+        else if (!ImageToolbox::IsNear(width, instances_[i]->GetImagedVolumeWidth()) ||
+                 !ImageToolbox::IsNear(height, instances_[i]->GetImagedVolumeHeight()))
+        {
+          LOG(WARNING) << "Inconsistency of imaged volume width/height in series: " << seriesId_;
+          return false;
+        }
+      }
+    }
+
+    return found;
   }
 }

--- a/Framework/Inputs/DicomPyramidInstance.cpp	Mon Apr 07 18:08:06 2025 +0200
+++ b/Framework/Inputs/DicomPyramidInstance.cpp	Mon Apr 07 18:41:34 2025 +0200
@@ -309,7 +309,9 @@
     backgroundBlue_(0),
     hasImagedVolumeSize_(false),
     imagedVolumeWidth_(0),
-    imagedVolumeHeight_(0)
+    imagedVolumeHeight_(0),
+    hasLevel_(false),
+    level_(0)
   {
     if (useCache)
     {
@@ -574,4 +576,25 @@
       throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
     }
   }
+
+
+  void DicomPyramidInstance::SetLevel(unsigned int level)
+  {
+    if (hasLevel_)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
+    }
+    else
+    {
+      level_ = level;
+      hasLevel_ = true;
+    }
+  }
+
+
+  bool DicomPyramidInstance::IsLevel(unsigned int level) const
+  {
+    return (hasLevel_ &&
+            level_ == level);
+  }
 }

--- a/Framework/Inputs/DicomPyramidInstance.h	Mon Apr 07 18:08:06 2025 +0200
+++ b/Framework/Inputs/DicomPyramidInstance.h	Mon Apr 07 18:41:34 2025 +0200
@@ -54,6 +54,8 @@
     bool                                hasImagedVolumeSize_;
     double                              imagedVolumeWidth_;
     double                              imagedVolumeHeight_;
+    bool                                hasLevel_;
+    unsigned int                        level_;
 
     void Load(OrthancStone::IOrthancConnection&  orthanc,
               const std::string& instanceId);
@@ -137,5 +139,9 @@
     double GetImagedVolumeWidth() const;
 
     double GetImagedVolumeHeight() const;
+
+    void SetLevel(unsigned int level);
+
+    bool IsLevel(unsigned int level) const;
   };
 }

--- a/Framework/Inputs/DicomPyramidLevel.cpp	Mon Apr 07 18:08:06 2025 +0200
+++ b/Framework/Inputs/DicomPyramidLevel.cpp	Mon Apr 07 18:41:34 2025 +0200
@@ -24,8 +24,6 @@
 #include "../PrecompiledHeadersWSI.h"
 #include "DicomPyramidLevel.h"
 
-#include "../ImageToolbox.h"
-
 #include <Logging.h>
 #include <OrthancException.h>
 
@@ -173,35 +171,4 @@
       return false;
     }
   }
-
-
-  bool DicomPyramidLevel::LookupImagedVolumeSize(double& width,
-                                                 double& height,
-                                                 const std::string& seriesId) const
-  {
-    bool found = false;
-
-    for (size_t i = 0; i < tiles_.size(); i++)
-    {
-      assert(tiles_[i].instance_ != NULL);
-
-      if (tiles_[i].instance_->HasImagedVolumeSize())
-      {
-        if (!found)
-        {
-          found = true;
-          width = tiles_[i].instance_->GetImagedVolumeWidth();
-          height = tiles_[i].instance_->GetImagedVolumeHeight();
-        }
-        else if (!ImageToolbox::IsNear(width, tiles_[i].instance_->GetImagedVolumeWidth()) ||
-                 !ImageToolbox::IsNear(height, tiles_[i].instance_->GetImagedVolumeHeight()))
-        {
-          LOG(WARNING) << "Inconsistency of imaged volume width/height in series: " << seriesId;
-          return false;
-        }
-      }
-    }
-
-    return found;
-  }
 }

--- a/Framework/Inputs/DicomPyramidLevel.h	Mon Apr 07 18:08:06 2025 +0200
+++ b/Framework/Inputs/DicomPyramidLevel.h	Mon Apr 07 18:41:34 2025 +0200
@@ -93,9 +93,5 @@
                          OrthancStone::IOrthancConnection& orthanc,
                          unsigned int tileX,
                          unsigned int tileY) const;
-
-    bool LookupImagedVolumeSize(double& width,
-                                double& height,
-                                const std::string& seriesId) const;
   };
 }