Packetcable™ 1.5 Specifications Audio/Video Codecs (PKT-SP

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Packetcable™ 1.5 Specifications Audio/Video Codecs (PKT-SP PacketCable™ 1.5 Specifications Audio/Video Codecs PKT-SP-CODEC1.5-I02-070412 ISSUED Notice This PacketCable specification is a cooperative effort undertaken at the direction of Cable Television Laboratories, Inc. (CableLabs®) for the benefit of the cable industry. Neither CableLabs, nor any other entity participating in the creation of this document, is responsible for any liability of any nature whatsoever resulting from or arising out of use or reliance upon this document by any party. This document is furnished on an AS-IS basis and neither CableLabs, nor other participating entity, provides any representation or warranty, express or implied, regarding its accuracy, completeness, or fitness for a particular purpose. © Copyright 2004-2007 Cable Television Laboratories, Inc. All rights reserved. PKT-SP-CODEC1.5-I02-070412 PacketCable™ 1.5 Specifications Document Status Sheet Document Control Number: PKT-SP-CODEC1.5-I02-070412 Document Title: Audio/Video Codecs Revision History: I01 – January 28, 2005 I02 – April 12, 2007 Date: April 12, 2007 Status: Work in Draft Issued Closed Progress Distribution Restrictions: Author CL/Member CL/ Public Only Member/ Vendor Key to Document Status Codes: Work in An incomplete document designed to guide discussion and generate Progress feedback that may include several alternative requirements for consideration. Draft A document in specification format considered largely complete, but lacking review by Members and vendors. Drafts are susceptible to substantial change during the review process. Issued A stable document, which has undergone rigorous member and vendor review and is suitable for product design and development, cross-vendor interoperability, and for certification testing. Closed A static document, reviewed, tested, validated, and closed to further engineering change requests to the specification through CableLabs. Trademarks: DOCSIS®, eDOCSISTM, PacketCableTM, CableHome®, CableOfficeTM, OpenCableTM, CableCARDTM and CableLabs® are trademarks of Cable Television Laboratories, Inc. ii CableLabs® 04/12/07 Audio/Video Codecs PKT-SP-CODEC1.5-I02-070412 Contents 1 SCOPE ....................................................................................................................... 1 1.1 INTRODUCTION AND OVERVIEW .......................................................................... 1 1.2 PURPOSE OF THE DOCUMENT ............................................................................... 1 1.3 ORGANIZATION OF DOCUMENT............................................................................ 1 1.4 REQUIREMENTS SYNTAX ..................................................................................... 2 1.5 PHASING OF REQUIREMENTS................................................................................ 2 2 REFERENCES.......................................................................................................... 3 2.1 NORMATIVE REFERENCES.................................................................................... 3 2.2 INFORMATIVE REFERENCES ................................................................................. 4 2.3 REFERENCE ACQUISITION .................................................................................... 5 3 TERMS AND DEFINITIONS ................................................................................. 6 4 ABBREVIATIONS AND ACRONYMS............................................................... 10 5 BACKGROUND ..................................................................................................... 17 5.1 PACKETCABLE VOICE COMMUNICATIONS QUALITY REQUIREMENTS................ 17 5.2 NETWORK PREPARATION FOR CODEC SUPPORT................................................. 17 5.2.1 Packet Loss Control.................................................................................. 17 5.2.2 Latency Control ........................................................................................ 17 5.2.3 Codec Transcoding Minimization............................................................. 19 5.2.4 Bandwidth Minimization........................................................................... 19 6 DEVICE REQUIREMENTS FOR AUDIO CODEC SUPPORT ...................... 20 6.1 DYNAMIC UPDATE CAPABILITY......................................................................... 20 6.2 MAXIMUM SERVICE OUTAGE............................................................................. 20 6.3 MINIMUM PROCESSING CAPABILITY.................................................................. 20 6.4 MINIMUM AUDIO CODEC STORAGE CAPABILITY ............................................... 21 7 AUDIO CODECS SPECIFICATIONS................................................................. 23 7.1 FEATURE SUPPORT............................................................................................. 23 7.1.1 DTMF Support.......................................................................................... 23 7.1.2 Fax and Modem Support........................................................................... 23 7.1.3 Echo Compensation Support..................................................................... 24 7.1.4 Asymmetrical Services Support................................................................. 24 7.1.5 Hearing-impaired Services Support ......................................................... 24 7.1.6 A-law and μ-law Support.......................................................................... 25 7.1.7 Packet Loss Concealment. ........................................................................ 25 7.1.8 Fax Relay .................................................................................................. 25 7.1.9 DTMF Relay.............................................................................................. 26 7.1.10 V.152 Transmission................................................................................... 27 7.1.11 Security Considerations............................................................................ 29 7.2 MANDATORY CODECS ....................................................................................... 29 7.2.1 G.711......................................................................................................... 29 04/12/07 CableLabs® iii PKT-SP-CODEC1.5-I02-070412 PacketCable™ 1.5 Specifications 7.3 RECOMMENDED CODECS ................................................................................... 29 7.3.1 iLBC .......................................................................................................... 30 7.3.2 BV16.......................................................................................................... 30 7.4 OPTIONAL CODECS ............................................................................................ 30 7.4.1 G.728......................................................................................................... 30 7.4.2 G.729 Annex E .......................................................................................... 30 7.5 OPTIONAL FEATURES......................................................................................... 30 7.5.1 Wideband Codecs...................................................................................... 30 7.5.2 Optional Codecs........................................................................................ 30 7.5.3 Voice Activity Detection (VAD) ................................................................ 30 7.6 SESSION DESCRIPTION OF CODECS..................................................................... 31 7.6.1 iLBC Session Description ......................................................................... 35 7.6.2 BV16 Session Description......................................................................... 35 8 VIDEO REQUIREMENTS.................................................................................... 36 8.1 OVERVIEW ......................................................................................................... 36 8.2 PACKETCABLE VIDEO DEVICES......................................................................... 36 8.3 VIDEO ENCODER REQUIREMENTS ...................................................................... 36 8.4 VIDEO FORMAT REQUIREMENTS........................................................................ 36 8.5 H.263 ANNEXES ................................................................................................ 38 8.6 MULTIPOINT CONFERENCING SUPPORT ............................................................. 40 8.6.1 Freeze Picture Request ............................................................................. 40 8.6.2 Fast Update Request................................................................................. 41 8.6.3 Freeze Picture Release ............................................................................. 41 8.6.4 Continuous Presence Multipoint (CPM) .................................................. 41 8.7 SIGNALING MESSAGES....................................................................................... 41 9 RTP AND RTCP USAGE ...................................................................................... 44 9.1 RTP REQUIREMENTS ......................................................................................... 44 9.2 RTCP REQUIREMENTS....................................................................................... 44 9.2.1 General Requirements of the PacketCable RTCP Profile ........................ 44 9.2.2
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