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 n ITU-T G.711.1 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 (10/2014) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital terminal equipments Coding of voice and audio signals Wideband emb
2、edded extension for G.711 PCM Amendment 1: New Annex G An alternative implementation of stereo super-wideband extension using floating point Recommendation ITU-T G.711.1 (2012) Amendment 1 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEP
3、HONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RAD
4、IO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 General G.700G.709 Coding of voice and audio signals G.
5、710G.729 Principal characteristics of primary multiplex equipment G.730G.739 Principal characteristics of second order multiplex equipment G.740G.749 Principal characteristics of higher order multiplex equipment G.750G.759 Principal characteristics of transcoder and digital multiplication equipment
6、G.760G.769 Operations, administration and maintenance features of transmission equipment G.770G.779 Principal characteristics of multiplexing equipment for the synchronous digital hierarchy G.780G.789 Other terminal equipment G.790G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE S
7、YSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, p
8、lease refer to the list of ITU-T Recommendations. Rec. ITU-T G.711.1 (2012)/Amd.1 (10/2014) i Recommendation ITU-T G.711.1 Wideband embedded extension for ITU-T G.711 PCM Amendment 1 New Annex G An alternative implementation of stereo super-wideband extension using floating point Summary Amendment 1
9、 to Recommendation ITU-T G.711.1 introduces Annex G, which provides a list of software routines, their description and associated C-code for a reference floating-point implementation of the ITU-T G.711.1 Annex F coding algorithm. The electronic attachment contains ANSI-C source code, which is an int
10、egral part of Annex G. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.711.1 2008-03-15 16 11.1002/1000/9365 1.1 ITU-T G.711.1 (2008) Amd. 1 2008-11-13 16 11.1002/1000/9632 1.2 ITU-T G.711.1 (2008) Amd. 2 2009-03-16 16 11.1002/1000/9686 1.3 ITU-T G.711.1 (2008) Amd. 3 2010
11、-10-14 16 11.1002/1000/10989 1.4 ITU-T G.711.1 (2008) Amd. 4 2010-11-13 16 11.1002/1000/11023 1.5 ITU-T G.711.1 (2008) Amd. 5 2011-03-25 16 11.1002/1000/11330 2.0 ITU-T G.711.1 2012-09-13 16 11.1002/1000/11672 2.1 ITU-T G.711.1 (2012) Amd. 1 2014-10-14 16 11.1002/1000/12231 _ * To access the Recomme
12、ndation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T G.711.1 (2012)/Amd.1 (10/2014) FOREWORD The International Telecommunication Union (ITU) is the Unite
13、d Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommenda
14、tions 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 the ITU-T study groups which, in turn, produce Recommendations on these topics. The appro
15、val 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 are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administrati
16、on“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and complianc
17、e with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is re
18、quired of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intelle
19、ctual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. Howev
20、er, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the pri
21、or written permission of ITU. Rec. ITU-T G.711.1 (2012)/Amd.1 (10/2014) 1 Recommendation ITU-T G.711.1 Wideband embedded extension for G.711 PCM Amendment 1 New Annex G An alternative implementation of stereo super-wideband extension using floating point Annex G Floating-point implementation of ITU-
22、T G.711.1 Annex F1 (This annex forms an integral part of this Recommendation.) G.1 Algorithmic description This floating-point version of ITU-T G.711.1 Annex F has the same algorithm steps as the fixed-point version. Similarly, the bitstream is identical to that of ITU-T G.711.1 Annex F. For algorit
23、hmic details, see the main body of the Recommendation and Annex F. G.2 ANSI C code ANSI C source code, simulating the floating-point version of ITU-T G.711.1 Annex F defined in this annex, is available as an electronic attachment to Annex G. The current version of this ANSI C source code is Version
24、1.0 of September 2012. The structure of the floating-point source code is related to the corresponding fixed point source code. Tables G.1 to G.3 give the list of the software filenames with a brief description. Note that files related to basic operators or mathematical operations are not used for f
25、loating-point arithmetic. A set of floating-point related routines have been added as floatutil.c. Table G.1 Summary of encoder specific routines Filename Description encoder.c ITU-T G.711.1 stereo encoder interface routine g711_stereo_enc.c ITU-T G.711.1 stereo main encoder get_interchannel_differe
26、nce.c Routines for whole wideband inter channel differences (IPD, ITD and IC) estimation Table G.2 Summary of decoder specific routines Filename Description decoder.c ITU-T G.711.1 stereo decoder interface routine g711_stereo_dec.c ITU-T G.711.1 stereo main decoder _ 1 Electronic attachment: ANSI-C
27、source code for ITU-T G.711.1 (2012) Amendment 1. 2 Rec. ITU-T G.711.1 (2012)/Amd.1 (10/2014) Table G.3 Summary of common routines Filename Description fft.c FFT routine stereo_tools.c Routines for read/write stereo bitstream and phase calculation table_stereo.c Tables for stereo encoder and decoder
28、 Printed in Switzerland Geneva, 2015 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D General tariff principles Series E Overall network operation, telephone service, service operation and human factors Series F Non-telephone telecommunication services Series G Tra
29、nsmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Series K Protection against interference Series L Co
30、nstruction, installation and protection of cables and other elements of outside plant Series M Telecommunication management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specifications of measuring equipment S
31、eries P Terminals and subjective and objective assessment methods Series Q Switching and signalling Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects and next-generation networks Series Z Languages and general software aspects for telecommunication systems