3 Definitions, symbols and abbreviations

26.4483GPPCodec for Enhanced Voice Services (EVS)Jitter Buffer ManagementRelease 17TS

3.1 Definitions

For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].

3.2 Symbols

For the purposes of the present document, the following symbols apply:

Time signal and time index n in context x, e.g. x can be inp, out, HP, pre, etc.

Frame length / size of module x

Energy values in context of x

Correlation function in context x

3.3 Abbreviations

For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905 [1].

AMR Adaptive Multi Rate (codec)

AMR-WB Adaptive Multi Rate Wideband (codec)

CNG Comfort Noise Generator

DTX Discontinuous Transmission

EVS Enhanced Voice Services

FB Fullband

FIFO First In, First Out

IP Internet Protocol

JBM Jitter Buffer Management

MTSI Multimedia Telephony Service for IMS

NB Narrowband

PCM Pulse Code Modulation

PLC Packet Loss Concealment

RTP Real Time Transport Protocol

SID Silence Insertion Descriptor

SOLA Synchronized overlap-add

SWB Super Wideband

TSM Time Scale Modification

VAD Voice Activity Detection

WB Wideband

3.4 Mathematical Expressions

For the purposes of the present document, the following conventions apply to mathematical expressions:

indicates the smallest integer greater than or equal to x: , and

indicates the largest integer less than or equal to x: , and

min(x₀,…x_N–1) indicates the minimum of x₀,…, x_N–1, N being the number of components

max(x₀,…x_N–1) indicates the maximum of x₀, …, x_N–1

indicates summation