- CASPAR_THROW_EXCEPTION(caspar_exception() << msg_info(std::string("Could not cast from ") + typeid(T).name() + " to " + typeid(I).name() + ". This is probably due to old Decklink drivers."));
+ if (!optional && !result)
+ CASPAR_THROW_EXCEPTION(not_supported() << msg_info(std::string("Could not cast from ") + typeid(T).name() + " to " + typeid(I).name() + ". This is probably due to old Decklink drivers."));