A 13.0 kbit/s wideband speech codec based on SB-ACELP

This paper describes a wideband (7 kHz) speech compression scheme operating at a bit rate of 13.0 kbit/s, i.e. 0.8 bit per sample. We apply a split-band (SB) technique, where the 0-6 kHz band is critically subsampled and coded by an ACELP approach. The high frequency signal components (6-7 kHz) are generated by an improved high-frequency-resynthesis (HFR) at the decoder such that no additional information has to be transmitted. In informal listening tests, the subjective speech quality was rated to be comparable to the CCITT G.722 wideband codec at 48 kbit/s.