SEI_USER_DATA_REGISTERED_TYPE is the only type of per-picture user data H264VideoDecoder understands for now. Is there any plans to add SEI_USER_DATA_UNREGISTERED_TYPE parsing, storing (at some m_UserData2 members eg) and returning to client (via some GetUserDataUnregistered method)?
Thanks for your report. At this moment, no much development plan to add the support now. It is sample code, and needs users to develop more feature.