1、 International Telecommunication Union ITU-T G.727TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Corrigendum 1(05/2005) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital terminal equipments Coding of analogue signals by methods other than PCM 5-, 4-, 3- and 2-bit/sample
2、 embedded Adaptive Differential Pulse Code Modulation (ADPCM) Corrigendum 1: Correction to Annex A: Extensions of Recommendation G.727 for use with uniform-quantized input and output ITU-T Recommendation G.727 (1990) Corrigendum 1 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITA
3、L SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE 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 INTE
4、RNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 General G.700G.709 Coding of anal
5、ogue signals by pulse code modulation G.710G.719 Coding of analogue signals by methods other than PCM G.720G.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 mult
6、iplex equipment G.750G.759 Principal characteristics of transcoder and digital multiplication equipment 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
7、.789 Other terminal equipment G.790G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 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 E
8、THERNET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. G.727 (1990)/Cor.1 (05/2005) i ITU-T Recommendation G.727 5-, 4-, 3- and 2-bit/sample embedded Adaptive Differential Pulse Code Modulation (ADPC
9、M) Corrigendum 1 Correction to Annex A: Extensions of Recommendation G.727 for use with uniform-quantized input and output Summary ITU-T Rec. G.727 contains the specification for the embedded adaptive differential PCM voice-coding algorithm at 16, 24, 32, and 40 kbit/s. Its Annex A contains the spec
10、ification for linear PCM input and output. This corrigendum fixes an omission in Decoder Block LIMO of Annex A/G.727, which limits the output linear twos complement sample to a 14-bit value. The pseudo-code, as originally published, misses the case for reconstructed samples SRFFequal to 57 344. Sour
11、ce Corrigendum 1 to ITU-T Recommendation G.727 (1990) was approved on 14 May 2005 by ITU-T Study Group 16 (2005-2008) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. G.727 (1990)/Cor.1 (05/2005) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized ag
12、ency in the field of telecommunications. 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 Recommendations on them with a view to standardizing telecommunications on a worldwid
13、e 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 approval of ITU-T Recommendations is covered by the procedure laid down in WTSA
14、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 “Administration“ is used for conciseness to indicate both a telecommunication administra
15、tion 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 compliance with the Recommendation is achieved when all of these mandatory provisions
16、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 required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the
17、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 Intellectual Property Rights, whether asserted by ITU members or others outside of
18、the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest in
19、formation and are therefore strongly urged to consult the TSB patent database. ITU 2005 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. G.727 (1990)/Cor.1 (05/2005) 1 ITU-T Recommendation G.727 5-, 4
20、-, 3- and 2-bit/sample embedded Adaptive Differential Pulse Code Modulation (ADPCM) Corrigendum 1 Correction to Annex A: Extensions of Recommendation G.727 for use with uniform-quantized input and output Description IIn the LIMO (decoder only) routine in A.3.5/G.727, Output limiting (decoder only),
21、“SRFF& 16 383, SRFF 57 344“ should be replaced with “SRFF& 16 383, SRFF 57 343“. The code is missing the case for SRFF= 57 344. Amend Block LIMO as indicated: LIMO (decoder only) Input: SRFF Output: SO Function: Limit output to 14-bit twos complement value | 8191, SRFF 8191 and SRFF 57 3434 | 57 344
22、, SRFF 32 767 and SRFF 57 344 Printed in Switzerland Geneva, 2005 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 telecommun
23、ication services Series G Transmission 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 aga
24、inst interference Series L Construction, 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 Specificat
25、ions of measuring equipment Series P Telephone transmission quality, telephone installations, local line networks 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
