The present document is a detailed description of the signal processing algorithms of the Enhanced Voice Services coder.
The detailed mapping from 20ms input blocks of audio samples in 16 bit uniform PCM format to encoded blocks of bits and from encoded blocks of bits to output blocks of reconstructed audio samples is explained.
Four sampling rates are supported; 8 000, 16 000, 32 000 and 48 000 samples/s and the bit rates for the encoded bit stream of may be 5.9, 7.2, 8.0, 9.6, 13.2, 16.4, 24.4, 32.0, 48.0, 64.0, 96.0 or 128.0 kbit/s. An AMR-WB Interoperable mode is also provided which operates at bit rates for the encoded bit stream of 6.6, 8.85, 12.65, 14.25, 15.85, 18.25, 19.85, 23.05 or 23.85 kbit/s.
The procedure of this document is mandatory for implementation in all network entities and User Equipment (UE)s supporting the EVS coder.
for V12, V13, V14:
(F) Corrections to the Algorithmic Description
(F) Handling of hf-only parameter