This code is part of the Liquid Argon Software (LArSoft) project. It contains simulation and reconstruction algorithms for LAr TPC detectors. If you have a problem, please log a redmine issue: https://cdcvs.fnal.gov/redmine/projects/larsoft/issues/new
Recob::OpWaveform is an intermediate class between raw::OpDetWaveform and recob::OpHits. Right now raw::OpDetWaveform provides a timestamp of double type, and recob::OpHits require also a double, however recob::OpWaveform stores the timestamp as a raw::RDTimeStamp.
There is a PR in duneopdet to implement this class, and we are forced to read raw::OpDetWaveforms just to take the timestamp when creating OpHits, which looks quite inefficient: DUNE/duneopdet#27 (comment)
The timestamp type should be changed from recob::raw::RDTimeStamp to a double, or add a new member to store this double.