Spectral Band Replication
(SBR) Guessing the nontransmitted higher frequency range of a compressed audio file by some helper bits (transmiited with the stream) and the transmitted base band. SBR allows a restoration (not reconstruction) of the upper frequency range without lots of bits. It was developed by Coding Technology, and is useful for medium and high quality coding at low and medium data rates. It is used by Digital Radio Mondiale and MP3 Pro.