ITU-T G 722 2 CORR 1-2005 Wideband coding of speech at around 16 kbit s using Adaptive Multi-Rate Wideband (AMR-WB) Corrigendum 1 - Digital terminal equipments C Coding of analogue上.pdf

1、I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o nITU-T G.722.2TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITUCorrigendum 1(09/2005)SERIES G: TRANSMISSION SYSTEMS AND MEDIA,DIGITAL SYSTEMS AND NETWORKSDigital terminal equipments Coding of analogue signalsby methods other than PCMWid

2、eband coding of speech at around 16 kbit/susing Adaptive Multi-Rate Wideband (AMR-WB)Corrigendum 1ITU-T Recommendation G.722.2 (2003) Corrigendum 1ITU-T G-SERIES RECOMMENDATIONSTRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKSINTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199GENE

3、RAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMSG.200G.299INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONESYSTEMS ON METALLIC LINESG.300G.399GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMSON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WIT

4、H METALLICLINESG.400G.449COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499TRANSMISSION MEDIA CHARACTERISTICS G.600G.699DIGITAL TERMINAL EQUIPMENTS G.700G.799General G.700G.709Coding of analogue signals by pulse code modulation G.710G.719Coding of analogue signals by methods other than PCM

5、 G.720G.729Principal characteristics of primary multiplex equipment G.730G.739Principal characteristics of second order multiplex equipment G.740G.749Principal characteristics of higher order multiplex equipment G.750G.759Principal characteristics of transcoder and digital multiplication equipment G

6、760G.769Operations, administration and maintenance features of transmission equipment G.770G.779Principal characteristics of multiplexing equipment for the synchronous digital hierarchy G.780G.789Other terminal equipment G.790G.799DIGITAL NETWORKS G.800G.899DIGITAL SECTIONS AND DIGITAL LINE SYSTEM

7、G.900G.999QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATEDASPECTSG.1000G.1999TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999ETHERNET OVER TRANSPORT ASPECTS G.8000G.8999ACCESS NETWORKS G.9000G.9999For further details, please refer to the list

8、 of ITU-T Recommendations.ITU-T Rec. G.722.2 (2003)/Cor.1 (09/2005) iITU-T Recommendation G.722.2Wideband coding of speech at around 16 kbit/s using Adaptive Multi-Rate Wideband (AMR-WB)Corrigendum 1SummaryThis corrigendum details a number of corrections to the text and formulas in the main body of

9、ITU-TRec. G.722.2 in order to align the text with the C-code in Annex C. Also, a couple of corrections tothe Annex C electrical C-code attachment are presented.SourceCorrigendum 1 to ITU-T Recommendation G.722.2 (2003) was approved on 13 September 2005 byITU-T Study Group 16 (2005-2008) under the IT

10、U-T Recommendation A.8 procedure.ii ITU-T Rec. G.722.2 (2003)/Cor.1 (09/2005)FOREWORDThe International Telecommunication Union (ITU) is the United Nations specialized agency in the field oftelecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ ofITU. ITU-T

11、is responsible for studying technical, operating and tariff questions and issuingRecommendations on them with a view to standardizing telecommunications on a worldwide basis.The World Telecommunication Standardization Assembly (WTSA), which meets every four years,establishes the topics for study by

12、the ITU-T study groups which, in turn, produce Recommendations onthese topics.The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1.In some areas of information technology which fall within ITU-Ts purview, the necessary standards areprepared on a collaborat

13、ive basis with ISO and IEC.NOTEIn this Recommendation, the expression “Administration“ is used for conciseness to indicate both atelecommunication administration and a recognized operating agency.Compliance with this Recommendation is voluntary. However, the Recommendation may contain certainmandato

14、ry provisions (to ensure e.g. interoperability or applicability) and compliance with theRecommendation is achieved when all of these mandatory provisions are met. The words “shall“ or someother obligatory language such as “must“ and the negative equivalents are used to express requirements. Theuse o

15、f such words does not suggest that compliance with the Recommendation is required of any party.INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation mayinvolve the use of a claimed Intellectual Property Right. ITU takes no posit

16、ion concerning the evidence,validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or othersoutside of the Recommendation development process.As of the date of approval of this Recommendation, ITU had received notice of intellectual property,protected by p

17、atents, which may be required to implement this Recommendation. However, implementorsare cautioned that this may not represent the latest information and are therefore strongly urged to consult theTSB patent database.ITU 2005All rights reserved. No part of this publication may be reproduced, by any

18、means whatsoever, without theprior written permission of ITU.ITU-T Rec. G.722.2 (2003)/Cor.1 (09/2005) iiiCONTENTSPage1 Subclause 5.7 Adaptive codebook. 12 Subclause 5.8.3 Codebook search . 13 Subclause 6.1 Decoding and speech synthesis 14 Annex C (electronic attachment) file bits.h 25 Annex C (elec

19、tronic attachment) file const.h . 36 Electronic attachments 3ITU-T Rec. G.722.2 (2003)/Cor.1 (09/2005) 1ITU-T Recommendation G.722.2Wideband coding of speech at around 16 kbit/s using Adaptive Multi-Rate Wideband (AMR-WB)Corrigendum 11 Subclause 5.7 Adaptive codebookThe text in the second last parag

20、raph (before equation 39) should be as follows:Thus, for 8.85, 12.65, 14.25, 15.85, 18.25, 19.85, 23.05 or 23.85 kbit/s modes, there are twopossibilities to generate the adaptive codebook v(n), (n)vnv)( in the first path, or)()1()(11invibnviLPin the second path, where bLP = 0.18,0.64,0.18. The path

21、which resultsin minimum energy of the target signal x2(n) defined in Equation (40) is selected for the filteredadaptive codebook vector. For 6.60 and 8.85 kbit/s modes, v(n) is always:)()1()(11invibnviLP2 Subclause 5.8.3 Codebook searchThe text in the ninth paragraph should be as follows:The correla

22、tion at the numerator of the search criterion Qk is now given by:10)(pNiidR10)(pNiimdRand the energy at the denominator of the search criterion Qk is given by:201110),(2),(p pP NiNijjiNiii mmmmE3 Subclause 6.1 Decoding and speech synthesisThe text in step 1 should be as follows:The following steps a

23、re repeated for each subframe:1) Decoding of the adaptive codebook vector: The received pitch index (adaptive codebookindex) is used to find the integer and fractional parts of the pitch lag. The adaptivecodebook vector v(n) is found by interpolating the past excitation u(n) (at the pitch delay)usin

24、g the FIR filter described in 5.65.7. The received adaptive filter index is used to findout whether the filtered adaptive codebook is v1(n) = v(n) or)2(18.0)1(64.0)(18.0)(2nvnvnvnv .2 ITU-T Rec. G.722.2 (2003)/Cor.1 (09/2005)Equation 65 in Step 6 should be as follows:Finally, the gain is updated wit

25、h the value of the smoothed gain as follows:cc ggg)01(00cmmc gSgSg)1(0(65)Step 7 text should be modified as follows:7) Pitch enhancer: A pitch enhancer procedure modifies the total excitation )(nu by filteringthe fixed codebook excitation through an innovation filter whose frequency responseemphasiz

26、es the higher frequencies more than lower frequencies, and whose coefficients arerelated to the periodicity in the signal. A filter of the form11)(zczcZFpepeinno (66)where )1(125.0 vpe rc),1(125.0 vpe rcwith rv = (Ev Ec)/(Ev + Ec) as described above.The filtered fixed codevector is given by:)1()1()(

27、)(ncnccncnc pe (67)and the updated excitation is given by:)()()( ncgnvgnu cp(68)The above procedure can be done in one step by updating the excitation as follows:)1()1()()(ncnccgnunu pec (69)4 Annex C (electronic attachment) file bits.hC-code before the change:static const Word16 nb_of_bitsNUM_OF_MO

28、DES = NBBITS_7k,NBBITS_9k,NBBITS_12k,NBBITS_14k,NBBITS_16k,NBBITS_18k,NBBITS_20k,NBBITS_23k,NBBITS_24k,NBBITS_24k,NBBITS_SID;ITU-T Rec. G.722.2 (2003)/Cor.1 (09/2005) 3C-code after the change:static const Word16 nb_of_bitsNUM_OF_MODES = NBBITS_7k,NBBITS_9k,NBBITS_12k,NBBITS_14k,NBBITS_16k,NBBITS_18k

29、NBBITS_20k,NBBITS_23k,NBBITS_24k,NBBITS_24k,NBBITS_SID;5 Annex C (electronic attachment) file const.hC-code before the change:#define MODE_7k 0#define MODE_9k 1#define MODE_12k 2#define MODE_14k 3#define MODE_16k 4#define MODE_18k 5#define MODE_20k 6#define MODE_23k 7#define MODE_24k 8#define MRDTX

30、 10#define NUM_OF_MODES 11 /* see bits.h for bitsdefinition */C-code after the change:#define MODE_7k 0#define MODE_9k 1#define MODE_12k 2#define MODE_14k 3#define MODE_16k 4#define MODE_18k 5#define MODE_20k 6#define MODE_23k 7#define MODE_24k 8#define MRDTX 109#define NUM_OF_MODES 1110 /* see bits

31、h for bitsdefinition */6 Electronic attachmentsbits.h and const.h modules are zipped with the text of the corrigendum and are available for freedownload from the ITU publication website at http:/www.itu.int/ITU-T/publications/recs.html.Printed in SwitzerlandGeneva, 2005SERIES OF ITU-T RECOMMENDATIO

32、NSSeries A Organization of the work of ITU-TSeries D General tariff principlesSeries E Overall network operation, telephone service, service operation and human factorsSeries F Non-telephone telecommunication servicesSeries G Transmission systems and media, digital systems and networksSeries H Audio

33、visual and multimedia systemsSeries I Integrated services digital networkSeries J Cable networks and transmission of television, sound programme and other multimedia signalsSeries K Protection against interferenceSeries L Construction, installation and protection of cables and other elements of outs

34、ide plantSeries M Telecommunication management, including TMN and network maintenanceSeries N Maintenance: international sound programme and television transmission circuitsSeries O Specifications of measuring equipmentSeries P Telephone transmission quality, telephone installations, local line netw

35、orksSeries Q Switching and signallingSeries R Telegraph transmissionSeries S Telegraph services terminal equipmentSeries T Terminals for telematic servicesSeries U Telegraph switchingSeries V Data communication over the telephone networkSeries X Data networks, open system communications and securitySeries Y Global information infrastructure, Internet protocol aspects and next-generation networksSeries Z Languages and general software aspects for telecommunication systems