Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); LTE; IP Multimedia System (IMS) Messaging and Presence; Media formats and codecs (V11.0.0; 3GPP TS 26.141 version 11.0.0 Release 11)
"The present document specifies the basic media formats and codecs to be used in the IMS Messaging and Presence services@ including CSI. It defines the mandatory ""baseline"" set of media types for the services. Additionally@ it also targets to allow possible message content type enhancements@ either 3GPP-standardized or other generally used media types@ in a flexible way."