std::map<int, int> default_stream_mapping;
bool multichannel_mapping_mode = false; // Implicitly true if input_mapping_filename is nonempty.
std::string input_mapping_filename; // Empty for none.
std::map<int, int> default_stream_mapping;
bool multichannel_mapping_mode = false; // Implicitly true if input_mapping_filename is nonempty.
std::string input_mapping_filename; // Empty for none.