5.3 Frequency band tables

26.4043GPPEnhanced aacPlus encoder Spectral Band Replication (SBR) partEnhanced aacPlus general audio codecGeneral audio codec audio processing functionsRelease 17TS

The SBR encoder use these different frequency band tables:, , and , which are defined according to subclause 4.6.18.3.2 in [1]. The parameters needed to define all frequency band tables are transmitted in the SBR bitstream header. For SBR header bitstream elements enabled with either bs_header_extra_1 or bs_header_extra_1 there are default values and hence a transmission of these elements are only needed if they differ from the default value. Default values are defined in subclause 4.5.2.8.1 in [1]. The SBR header parameters are regarded as tuning parameters since they are strongly bitrate and sampling frequency dependant Throughout the tuning work for 3GPP submission several bitrate and sampling frequency dependant tunings have been created and in the reference c-code there are tunings available from 8kbit/s mono to 48 kbit/s stereo.