26101b00speech codec frame structure.docx

1、26101b00speech codec frame structure3GPP TS 26.101 V11.0.0 (2012-09)Technical Specification3rd Generation Partnership Project;Technical Specification Group Services and System Aspects;Mandatory speech codec speech processing functions;Adaptive Multi-Rate (AMR) speech codec frame structure(Release 11

2、) The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP.The present document has not been subject to any approval process by the 3GPP Organizational Partners and shall not be implemented.This Specificati

3、on is provided for future development work within 3GPP only. The Organizational Partners accept no liability for any use of this Specification.Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organizational Partners Publications Offices.KeywordsGSM,

4、 UMTS, codec, AMR, LTE3GPPPostal address3GPP support office address650 Route des Lucioles - Sophia AntipolisValbonne - FRANCETel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16Internethttp:/www.3gpp.orgCopyright NotificationNo part may be reproduced except as authorized by written permission.The copyrigh

5、t and the foregoing restriction extend to reproduction in all media. 2012, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC).All rights reserved.UMTS is a Trade Mark of ETSI registered for the benefit of its members3GPP is a Trade Mark of ETSI registered for the benefit of its Members

6、and of the 3GPP Organizational PartnersLTE is a Trade Mark of ETSI currently being registered for the benefit of its Members and of the 3GPP Organizational PartnersGSM and the GSM logo are registered and owned by the GSM AssociationContentsForeword 41 Scope 52 References 53 Definitions and Abbreviat

7、ions 53.1 Definitions 53.2 Abbreviations 54 AMR codec frame format (AMR IF1) 64.1 AMR Header and AMR Auxiliary Information 64.1.1 Frame Type, Mode Indication, and Mode Request 64.1.2 Frame Quality Indicator 74.1.3 Mapping to TX_TYPE and RX_TYPE 74.1.4 Codec CRC 84.2 AMR Core Frame 84.2.1 AMR Core Fr

8、ame with speech bits: Bit ordering 84.2.2 AMR Core Frame with speech bits: Class division 94.2.3 AMR Core Frame with comfort noise bits 94.3 AMR frame composition 104.4 GSM-EFR Frame Composition 114.4.1 GSM-EFR Frame with speech bits 124.4.2 GSM-EFR Frame with comfort noise bits 12Annex A (informati

9、ve): AMR Interface Format 2 (with octet alignment) 13Annex B (normative): Tables for AMR Core Frame bit ordering 17Annex C (informative): Change history 20ForewordThis Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP).The contents of the present document are

10、subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows:Version x.y.zwhere:x the first

11、 digit:1 presented to TSG for information;2 presented to TSG for approval;3 or greater indicates TSG approved document under change control.y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc.z the third digit is incremented when edi

12、torial only changes have been incorporated in the document.1 ScopeThe present document describes a generic frame format for the Adaptive Multi-Rate (AMR) speech codec and the Enhanced Full Rate (GSM-EFR) speech codec. This format shall be used as a common reference point when interfacing speech fram

13、es between different elements of the 3G system and between different systems. Appropriate mappings to and from this generic frame format will be used within and between each system element.Annex A describes a second frame format which shall be used when octet alignment of AMR frames is required.2 Re

14、ferencesThe following documents contain provisions which, through reference in this text, constitute provisions of the present document. References are either specific (identified by date of publication, edition number, version number, etc.) or nonspecific. For a specific reference, subsequent revis

15、ions do not apply. For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.1 TS26.090: AMR Speech

16、Codec; Speech Transcoding Functions.2 TS26.093: AMR Speech Codec; Source Controlled Rate Operation.3 TS26.092: AMR Speech Codec; Comfort Noise Aspects.4 TS46.060: EFR Speech Codec; Speech Transcoding Functions.5 TS46.062: EFR Speech Codec; Comfort Noise Aspects.3 Definitions and Abbreviations3.1 Def

17、initionsFor the purposes of the present document, the following terms and definitions apply:AMR mode: one of the eight AMR codec bit-rates denoted also with indices 0 to 7 where 0 maps to the 4.75 kbis/s mode and 7 maps to the 12.2kbit/s mode.AMR codec mode: same as AMR mode.RX_TYPE: classification

18、of the received frame as defined in 2.TX_TYPE: classification of the transmitted frame as defined in 2.3.2 AbbreviationsFor the purposes of the present document, the following abbreviations apply:CRC Cyclic Redundancy CheckFQI Frame Quality IndicatorGSM Global System for Mobile communicationLSB Leas

19、t Significant BitMSB Most Significant BitRX ReceivePDC Personal Digital Communication (ARIB standard)SCR Source Controlled Rate operationSID Silence Descriptor (Comfort Noise Frame)TDMA Time Division Multiple Access (IS-641)TX Transmit4 AMR codec frame format (AMR IF1)This clause describes the gener

20、ic frame format for both the speech and comfort noise frames of the AMR speech codec. This format is referred to as AMR Interface Format 1 (AMR IF1). Annex A describes AMR Interface Format2 (AMRIF2).Each AMR codec mode follows the generic frame structure depicted in figure 1. The frame is divided in

21、to three parts: AMR Header, AMR Auxiliary Information, and AMR Core Frame. The AMR Header part includes the Frame Type and the Frame Quality Indicator fields. The AMR auxiliary information part includes the Mode Indication, Mode Request, and Codec CRC fields. The AMR Core Frame part consists of the

22、speech parameter bits or, in case of a comfort noise frame, the comfort noise parameter bits. In case of a comfort noise frame, the comfort noise parameters replace Class A bits of AMR Core Frame while Class B and C bits are omitted.Figure 1: Generic AMR frame structure4.1 AMR Header and AMR Auxilia

23、ry InformationThis subclause describes the AMR Header of figure1.4.1.1 Frame Type, Mode Indication, and Mode RequestTable 1a defines the 4-bit Frame Type field. Frame Type can indicate the use of one of the eight AMR codec modes, one of four different comfort noise frames, or an empty frame. In addi

24、tion, three Frame Type Indices are reserved for future use. The same table is reused for the Mode Indication and Mode Request fields which are 3-bit fields each and are defined only in the range 07 to specify one of the eight AMR codec modes.Table 1a: Interpretation of Frame Type,Mode Indication and

25、 Mode Request fieldsFrame TypeMode IndicationMode RequestFrame content (AMR mode, comfort noise, or other)000AMR 4,75 kbit/s 111AMR 5,15 kbit/s 222AMR 5,90 kbit/s 333AMR 6,70 kbit/s (PDC-EFR)444AMR 7,40 kbit/s (TDMA-EFR)555AMR 7,95 kbit/s 666AMR 10,2 kbit/s 777AMR 12,2 kbit/s (GSM-EFR)8-AMR SID9-GSM

26、-EFR SID10-TDMA-EFR SID 11-PDC-EFR SID12-14-For future use15-No Data (No transmission/No reception) 4.1.2 Frame Quality IndicatorThe content of the Frame Quality Indicator field is defined in Table 1b. The field length is one bit. The Frame Quality Indicator indicates whether the data in the frame c

27、ontains errors.Table 1b: Definition of Frame Quality IndicatorFrame Quality Indicator (FQI)Quality of data0Bad frame or Corrupted frame(bits may be used to assist error concealment)1Good frame4.1.3 Mapping to TX_TYPE and RX_TYPETable1c shows how the AMR Header data (FQI and Frame Type) maps to the T

28、X_TYPE and RX_TYPE frames defined in 2.Table 1c: Mapping of Frame Quality Indicator and Frame Type toTX_TYPE and RX_TYPE 2, respectivelyFrame Quality Indicator Frame Type Index TX_TYPE orRX_TYPEComment10-7SPEECH_GOODThe specific Frame Type Index depends on the bit-rate being used.00-7SPEECH_BADThe s

29、pecific Frame Type Index depends on the bit-rate being used. The corrupted data may be used to assist error concealment.188SID_FIRST or SID_UPDATEFor AMR: SID_FIRST and SID_UPDATEare differentiated using one ClassA bit: STI.08SID_BADFor AMR19GSM-EFR SIDFor GSM-EFR09GSM-EFR SID_BADFor GSM-EFR110-11SI

30、D_UPDATEFor TDMA-EFR and PDC-EFR010-11SID_BADFor TDMA-EFR and PDC-EFR115NO_DATATypically a non-transmitted frame or an erased or stolen frame with no data usable to assist error concealment.4.1.4 Codec CRCGeneric AMR codec frames with Frame Type0.11 are associated with an 8-bit CRC for error-detecti

31、on purposes. The Codec CRC field of AMR Auxiliary Information in figure1 contains the value of this CRC. These eight parity bits are generated by the cyclic generator polynomial:- G(x)=D8 + D6 + D5 + D4 + 1which is computed over all ClassA bits of AMR Core Frame. ClassA bits for Frame Types 0.7 are defined in subclause4.2.2 (for speech bits) and for Frame Types 8.11 in subclause4.2.3 (for comfort noise bits).When Frame Type Index of table