feat(Image): support metadata serialization

include/itkImageToWASMImageFilter.hxx

@@ -21,6 +21,7 @@
 #include "itkImageToWASMImageFilter.h"
 
 #include "itkDefaultConvertPixelTraits.h"
+#include "itkMetaDataDictionaryJSON.h"
 
 #include "itkWASMMapComponentType.h"
 #include "itkWASMMapPixelType.h"
@@ -203,6 +204,11 @@ ImageToWASMImageFilter<TImage>
   dataString.SetString( dataStream.str().c_str(), allocator );
   document.AddMember( "data", dataString.Move(), allocator );
 
+  auto dictionary = image->GetMetaDataDictionary();
+  rapidjson::Value metadataJson(rapidjson::kArrayType);
+  wasm::ConvertMetaDataDictionaryToJSON(dictionary, metadataJson, allocator);
+  document.AddMember( "metadata", metadataJson.Move(), allocator );
+
   rapidjson::StringBuffer stringBuffer;
   rapidjson::Writer<rapidjson::StringBuffer> writer(stringBuffer);
   document.Accept(writer);

include/itkMetaDataDictionaryJSON.h

@@ -0,0 +1,42 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+#ifndef itkMetaDataDictionaryJSON_h
+#define itkMetaDataDictionaryJSON_h
+
+#include "itkMetaDataDictionary.h"
+#include "itkDefaultConvertPixelTraits.h"
+#include "itkMetaDataObject.h"
+#include "itkArray.h"
+#include "itkMatrix.h"
+
+#include "rapidjson/document.h"
+
+namespace itk
+{
+
+namespace wasm
+{
+
+void ConvertMetaDataDictionaryToJSON(const itk::MetaDataDictionary & dictionary, rapidjson::Value & metadataJson, rapidjson::Document::AllocatorType& allocator);
+
+void ConvertJSONToMetaDataDictionary(const rapidjson::Value & metadataJson, itk::MetaDataDictionary & dictionary);
+
+} // end namespace wasm
+} // end namespace itk
+
+#endif

include/itkWASMImageToImageFilter.hxx

@@ -20,11 +20,13 @@
 
 #include "itkWASMImageToImageFilter.h"
 
+#include "itkMetaDataDictionaryJSON.h"
 #include "itkImportVectorImageFilter.h"
 #include <exception>
 #include "itkWASMMapComponentType.h"
 #include "itkWASMMapPixelType.h"
 #include "itkDefaultConvertPixelTraits.h"
+#include "itkMetaDataObject.h"
 
 #include "rapidjson/document.h"
 
@@ -229,9 +231,16 @@ WASMImageToImageFilter<TImage>
     {
     filter->SetImportPointer( dataPtr, totalSize, letImageContainerManageMemory);
     }
-
   filter->Update();
   image->Graft(filter->GetOutput());
+
+  if (document.HasMember("metadata"))
+  {
+    auto dictionary = image->GetMetaDataDictionary();
+    const rapidjson::Value & metadataJson = document["metadata"];
+    wasm::ConvertJSONToMetaDataDictionary(metadataJson, dictionary);
+  }
+
 }
 
 template <typename TImage>

src/CMakeLists.txt

@@ -2,6 +2,7 @@ include_directories(${WebAssemblyInterface_INCLUDE_DIRS})
 
 set(WebAssemblyInterface_SRCS
   itkPipeline.cxx
+  itkMetaDataDictionaryJSON.cxx
   itkWASMExports.cxx
   itkWASMDataObject.cxx
   itkWASMImageIOBase.cxx