An 64-80-96 kbit/s scalable wideband speech coding candidate for ITU-T G.711-WB standardization

This article presents a bitrate- and bandwidth-scalable coder submitted as a candidate to the qualification phase of ITU-T embedded G.711 wideband (G.711-WB) standardization. The encoder operates on 5 ms frames and bitrate can be set on a frame basis at either 64, 80 or 96 kbit/s. The input signal, which is by default sampled at 16 kHz, is split in two bands. The low band (0-4000 Hz) is coded by a low-complexity embedded pulse code modulation (PCM) coder at 8-10 bits/sample, including noise feedback at the encoder and PCM-specific post-filtering at the decoder. The high-band (4000- 8000 Hz) is coded by a time-domain aliasing cancellation (TDAC) coder derived from ITU-T G.729.1. Frame erasures are concealed using a low-complexity split-band algorithm derived from ITU-T G.722 Appendix IV. The proposed coder passed all requirements of the G.711WB qualification phase. We summarize and discuss formal ITU-T test results.