Flexible spectrum coding in the 3GPP EVS codec

This paper proposes a flexible encoding technique based on multi-stage multiple scale lattice vector quantization and block-constrained trellis coded vector quantization. It is used for the spectrum encoding, more precisely encoding of the LSF parameters, and incorporated in the recently standardized 3GPP EVS codec. The proposed method can handle multiple bit allocations and signal types with low complexity and low memory requirements.