Shared pointer instead of value copy

src/RingBuffer.hpp

@@ -22,7 +22,7 @@ struct FrameMetadata
     std::vector<size_t> frame_shape;
 
     // Pass additional header values.
-    std::map<std::string, boost::any> header_values;
+    std::map<std::string, std::shared_ptr<boost::any>> header_values;
 };
 
 class RingBuffer

src/ZmqReceiver.cpp

@@ -127,7 +127,7 @@ shared_ptr<FrameMetadata> ZmqReceiver::read_json_header(const string& header)
         
         const auto& name = value_mapping.first;
         const auto& data_type = value_mapping.second;
-        const boost::any& value = get_value_from_json(json_header, name, data_type);
+        auto value = make_shared<boost::any>(get_value_from_json(json_header, name, data_type));
 
         header_data->header_values.insert(
             {name, value}