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ITU-T G.722 (1988) App. IV (07/2007)
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ITU-T G.722 (1988) App. IV (07/2007)
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Algorithme de faible complexité pour le masquage des pertes de paquets pour le vocodeur G.722
Les algorithmes de masquage de perte de paquets (PLC, packet loss concealment), appelés également algorithmes de masquage d'effacement de trames, cachent les pertes de transmission dans le système audio où le signal d'entrée est codé et paquetisé, envoyé sur un réseau, reçu puis décodé avant d'être joué. Les algorithmes PLC sont utilisés dans la plupart des codeurs de signaux vocaux, basés CELP, standards. L'algorithme décrit ci-après fournit une méthode qui pourra être utilisée aux fins de [UIT-T G.722].Le décodeur comprend trois étages: un décodage en bande inférieure, un décodage en bande supérieure et une synthèse par filtres miroirs en quadrature (QMF, quadrature mirror filter). En l'absence d'effacement de trame, la structure du décodeur est identique à celle décrite précédemment dans la Rec. UIT-T G.722, sauf en ce qui concerne le stockage des deux signaux décodés des bandes inférieure et supérieure; en présence d'effacement de trame, le décodeur est informé par la signalisation indication de mauvaise trame (BFI, bad frame indication): il analyse alors le signal passé, reconstruit en bande inférieure, et extrapole le signal manquant par codage prédictif linéaire (LPC, linear-predictive coding), répétition de la période de pitch synchrone et atténuation (muting) adaptative. Lorsqu'une bonne trame est reçue, le signal décodé est combiné par fondu-enchaîné avec le signal extrapolé. Dans la bande supérieure, le décodeur répète de façon pitch synchrone la trame précédente avec atténuation adaptative et post-traitement passe-haut. Les états MICDA sont actualisés après chaque effacement de trame. L'algorithme PLC décrit dans le présent appendice offre les mêmes prescriptions de qualité que le PLC présenté à l'Appendice III de [UIT-T G.722], lequel offre une moindre complexité. Presque aucune complexité supplémentaire n'est ajoutée par rapport au décodage normal de la Recommandation G.722 (la complexité supplémentaire correspondant au cas le plus défavorable est de 0,07 WMOPS). L'Appendice III propose un autre compromis entre qualité et complexité.
Citation:
https://handle.itu.int/11.1002/1000/9212
Series title:
G series: Transmission systems and media, digital systems and networks
G.700-G.799: Digital terminal equipments
G.710-G.729: Coding of voice and audio signals
Approval date:
2007-07-06
Provisional name:
G.72x
Approval process:
Agreed
Status:
Superseded
Observation:
This Recommendation includes the release 1.1 of the ANSI-C code simulating the candidate G.722 low-complexity packet-loss concealment algorithm in 16-bit fixed-point
Maintenance responsibility:
ITU-T Study Group 16
Further details:
Patent statement(s)
Development history
Associated test signals
Editions
Related Supplement(s)
Related technical papers and reports
Ed.
ITU-T Recommendation
Status
Summary
Table of Contents
Download
3.1
G.722 (2012) Amd. 1 (10/2014)
In force
here
-
here
3
G.722 (09/2012)
In force
here
here
here
2.8
G.722 (1988) Amd. 2 (03/2011)
Superseded
here
-
here
2.7
G.722 (1988) Amd. 1 (11/2010)
Superseded
here
here
here
2.6
G.722 (1988) App. IV (11/2009)
Superseded
here
here
here
2.5
G.722 (1988) App. IV (07/2007)
Superseded
here
here
here
2.4
G.722 (1988) App. IV (11/2006)
Superseded
here
here
here
2.3
G.722 (1988) App. III (11/2006)
Superseded
here
here
here
2.2
G.722 (1988) Annex A (03/1993)
Superseded
here
here
here
2.1
G.722 (1988) App. II (11/1988)
Superseded
-
-
here
2.0
G.722 (1988) Err. 1 (05/2003)
Superseded
here
-
here
2
G.722 (11/1988)
Superseded
-
-
here
1
G.722 (02/1987)
Superseded
-
-
Not available
ITU-T Supplement
Title
Status
Summary
Table of contents
Download
G Suppl. 4 (12/1972)
Certain methods of avoiding the transmission of excessive noise between interconnected systems
In force
-
-
here
G Suppl. 5 (10/1984)
Measurement of the load of telephone circuits under field conditions
In force
-
-
here
G Suppl. 7 (12/1972)
Loss-frequency response of channel-translating equipment used in some countries for international circuits
In force
here
here
here
G Suppl. 8 (12/1972)
Method proposed by the Belgian telephone administration for interconnection between coaxial and symmetric pair systems
In force
-
-
here
G Suppl. 17 (10/1984)
Group-delay distortion performance of terminal equipment
In force
-
-
here
G Suppl. 19 (10/1984)
Digital crosstalk measurement (method used by the Administrations of France, the Netherlands and Spain)
In force
-
-
here
G Suppl. 22 (10/1984)
Mathematical models of multiplex signals
In force
-
-
here
G Suppl. 26 (10/1984)
Estimating the signal load margin of FDM wideband amplifier equipment and transmission systems
In force
-
-
here
G Suppl. 27 (10/1984)
Interference from external sources
In force
-
-
here
G Suppl. 28 (10/1984)
Application of transmultiplexers, FDM codecs, data-in-voice (DIV) systems and data-over-voice (DOV) systems during the transition from an analogue to a digital network
In force
-
-
here
G Suppl. 32 (11/1988)
Transfer of alarm information on 60-channel transmultiplexing equipment
In force
-
-
here
G Suppl. 34 (11/1988)
Temperature in underground containers for the installation of repeaters
In force
-
-
here
G Suppl. 35 (11/1988)
Guidelines concerning the measurement of wander
In force
-
-
here
G Suppl. 36 (11/1988)
Jitter and wander accumulation in digital networks
In force
-
-
here
G Suppl. 39 (02/2016)
Optical system design and engineering considerations
In force
here
here
here
G Suppl. 40 (10/2018)
Optical fibre and cable Recommendations and standards guideline
In force
here
here
here
G Suppl. 41 (02/2018)
Design guidelines for optical fibre submarine cable systems
In force
here
here
here
G Suppl. 42 (10/2018)
Guide on the use of the ITU-T Recommendations related to optical fibres and systems technology
In force
here
here
here
G Suppl. 43 (02/2011)
Transport of IEEE 10GBASE-R in optical transport networks (OTN)
In force
here
here
here
G Suppl. 44 (06/2007)
Test plan to verify B-PON interoperability
In force
here
here
here
G Suppl. 45 (09/2022)
Power conservation in optical access systems
In force
here
here
here
G Suppl. 46 (05/2009)
G-PON interoperability test plan between optical line terminations and optical network units
In force
here
here
here
G Suppl. 47 (09/2012)
General aspects of optical fibres and cables
In force
here
here
here
G Suppl. 48 (06/2010)
10-Gigabit-capable passive optical networks: Interface between media access control with serializer/deserializer and physical medium dependent sublayers
In force
here
here
here
G Suppl. 49 (09/2020)
Rogue optical network unit (ONU) considerations
In force
here
here
here
G Suppl. 50 (09/2011)
Overview of digital subscriber line Recommendations
In force
here
here
here
G Suppl. 51 (06/2017)
Passive optical network protection considerations
In force
here
here
here
G Suppl. 52 (09/2012)
Ethernet ring protection switching
In force
here
here
here
G Suppl. 53 (12/2014)
Guidance for Ethernet OAM performance monitoring
In force
here
here
here
G Suppl. 54 (07/2015)
Ethernet linear protection switching
In force
here
here
here
G Suppl. 55 (12/2023)
Radio-over-fibre (RoF) technologies and their applications
In force
here
here
here
G Suppl. 56 (02/2016)
OTN transport of CPRI signals
In force
here
here
here
G Suppl. 57 (07/2015)
Smart home profiles for 6LoWPAN devices
In force
here
here
here
G Suppl. 58 (12/2023)
Optical transport network module framer interfaces
In force
here
here
here
G Suppl. 59 (02/2018)
Guidance on optical fibre and cable reliability
In force
here
here
here
G Suppl. 60 (09/2016)
Ethernet linear protection switching with dual node interconnection
In force
here
here
here
G Suppl. 62 (02/2018)
Gfast certification
In force
here
here
here
G Suppl. 64 (02/2018)
PON transmission technologies above 10 Gb/s per wavelength
In force
here
here
here
G Suppl. 65 (10/2018)
Simulations of transport of time over packet networks
In force
here
here
here
G Suppl. 66 (09/2020)
5G wireless fronthaul requirements in a passive optical network context
In force
here
here
here
G Suppl. 67 (07/2019)
Application of optical transport network Recommendations to 5G transport
In force
here
here
here
G Suppl. 68 (12/2023)
Synchronization operations, administration and maintenance requirements
In force
here
here
here
G Suppl. 69 (09/2020)
Migration of a pre-standard network to a metro transport network
In force
here
here
here
G Suppl. 70 (09/2020)
Supplement on sub 1 Gbit/s services transport over optical transport network
In force
here
here
here
G Suppl. 71 (12/2023)
Optical line termination capabilities for supporting cooperative dynamic bandwidth assignment
In force
here
here
here
G Suppl. 72 (04/2021)
Modelling consideration for optical media networks
In force
here
here
here
G Suppl. 73 (10/2021)
Influencing factors on quality of experience for multiview video (MVV) services
In force
here
here
here
G Suppl. 74 (12/2021)
Network slicing in a passive optical network context
In force
here
here
here
G Suppl. 75 (12/2021)
5G small cell backhaul/midhaul over TDM-PON
In force
here
here
here
G Suppl. 76 (12/2021)
Optical transport network security
In force
here
here
here
G Suppl. 77 (06/2022)
Supplement 77 to ITU-T G-series of Recommendations - Influencing factors on quality of experience (QoE) for video customized alerting tone (CAT) and video customized ringing signal (CRS) services
In force
here
here
here
G Suppl. 78 (09/2022)
Use case and requirements of fibre-to-the-room for small business applications
In force
here
here
here
G Suppl. 79 (12/2023)
Latency control and deterministic capability over a PON system
In force
here
here
here
Title
Approved on
Download
Roadmap for QoS and QoE in the ITU-T Study Group 12 context (TR-RQ)
2023
here
Considerations on the use of GNSS as a primary time reference in telecommunications
2020
here
Use of G.hn in industrial applications
2020
here
Practical procedures for subjective testing
2011
here
ISDN field trial guidelines
1991
here
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