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TechSpec
  • Foreword
  • 1 Scope
  • 2 References
  • 3 Definitions, symbols and abbreviations
  • 4 General
  • 5 Detailed description
    • 5.1 Concealment operation related to signal classification
      • 5.1.1 Overview
      • 5.1.2 Signal class estimation
    • 5.2 Concealment operation related to spectral envelope (LPC) representation
      • 5.2 Concealment operation related to spectral envelope (LPC) representation
      • 5.2.1 Specifics to rates 9.6, 16.4 and 24.4kbps
      • 5.2.2 Specifics to AMR-WB IO mode
      • 5.2.3 Check for Mid LSF stability
      • 5.2.4 Adaptive interpolation of LSFs
      • 5.2.5 LPC gain compensation
    • 5.3 Concealment operation related to ACELP modes
      • 5.3.1 General
      • 5.3.2 Concealment for bandwidth extension for ACELP modes
      • 5.3.3 Guided concealment and recovery
      • 5.3.4 Handling of multiple frame losses and muting
    • 5.4 Concealment operation related to MDCT modes
      • 5.4.1 PLC method selection
      • 5.4.2 TCX MDCT
      • 5.4.3 HQ MDCT
      • 5.4.4 Void
      • 5.4.5 Guided concealment and recovery
      • 5.4.6 Handling of multiple frame losses and muting
    • 5.5 SID frame concealment operation

5.2.2 Specifics to AMR-WB IO mode

26.4473GPPCodec for Enhanced Voice Services (EVS)Error concealment of lost packetsRelease 17TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

The same procedure is performed, but instead of LSFs, ISFs are used for the estimation. The mean LSF vector used for interpolation is