"H.245音视频协议栈及其通信控制协议介绍"

需积分: 0 164 浏览量更新于2024-01-28 收藏 3.23MB PDF 举报

音视频协议栈h.245是国际电信联盟ITU-T H.245电信标准化部门（2022年3月）系列H：音频和多媒体系统-音频视听服务基础设施的通信程序控制协议，推荐ITU-T H.245。ITU-T H系列推荐-音频和多媒体系统-视听电话系统的特性H.100-H.199音频视听服务基础设施。 h.245协议是一种多媒体通信控制协议，为音视频传输提供了一套标准化的控制框架，可以用于多种多媒体通信场景中，包括视频电话、视频会议和多媒体广播等。该协议规定了音视频通信中的通信过程控制、媒体协商和参数协商等内容，确保音视频传输的稳定和高效。 ITU-T H.245协议对于多媒体通信来说至关重要，它提供了一种统一的控制框架，包括媒体格式协商、带宽协商、通道分配和单击连接等功能。通过这些功能，h.245协议可以实现多种多媒体通信场景中的音视频传输，并确保通信质量。在音视频通信中，h.245协议通过一系列的消息交换和协商过程，确保通信双方可以在多媒体通信会话中协商出合适的音视频编解码参数、传输格式以及带宽要求，这样可以最大程度地提高通信质量，同时也可以在不同的网络环境下保持传输的稳定性。 ITUT-T H.245协议为音视频通信提供了强大的支持，通过对音视频传输过程进行精细的控制，使得音视频通信可以在不同的场景下都拥有稳定的通信质量。同时，h.245协议的标准化也为各种音视频设备之间的互操作性提供了保障，使得不同厂家生产的音视频设备都可以很好地进行互联和通信。总的来说，ITU-T H.245协议是音视频通信中非常重要的一部分，它为多媒体通信提供了统一的控制框架，包括媒体格式协商、带宽协商、通道分配和单击连接等功能。通过这些功能，h.245协议可以实现多种多媒体通信场景中的音视频传输，并确保通信质量。同时，h.245协议的标准化也为各种音视频设备之间的互操作性提供了保障，使得不同厂家生产的音视频设备都可以很好地进行互联和通信。

 
xiv  Rec. ITU-T H.245 (03/2022) 
  Page 
Table G.3 – Capability Parameter profileAndLevel ........................................................................ 260 
Table G.4 – Capability Parameter objectType ................................................................................. 260 
Table G.5 – Capability Parameter objectDescriptor ........................................................................ 261 
Table G.6 – Capability Parameter ES_ID ........................................................................................ 261 
Table H.1 – Capability Identifier for ISO/IEC 14496-3 Capability ................................................. 262 
Table H.2 – Profile and Level for ISO/IEC 14496-3 Capability ..................................................... 262 
Table H.3 – formatType for ISO/IEC 14496-3 Capability .............................................................. 263 
Table H.4 – maxAl-sduAudioFrames for ISO/IEC 14496-3 Capability .......................................... 263 
Table H.5 – audioObjectType for ISO/IEC 14496-3 Capability ..................................................... 263 
Table H.6 – audioSpecificConfig for ISO/IEC 14496-3 Capability ................................................ 264 
Table H.7 – maxAudioObjects for ISO/IEC 14496-3 Capability .................................................... 264 
Table H.8 – muxConfigPresent for ISO/IEC 14496-3 Capability ................................................... 264 
Table H.9 – EP_DataPresent for ISO/IEC 14496-3 Capability ....................................................... 265 
Table H.10 – streamMuxConfig for ISO/IEC 14496-3 Capability .................................................. 265 
Table H.11 – errorProtection_SpecificConfig for ISO/IEC 14496-3 Capability ............................. 265 
Table I.1 – GSM AMR Capability Identifier ................................................................................... 266 
Table I.2 – GSM AMR Capability Parameter – maxAl-sduAudioFrames ...................................... 266 
Table I.3 – GSM AMR Capability Parameter – bitRate .................................................................. 266 
Table I.4 – GSM AMR Capability Parameter – GSM AMR Comfort Noise .................................. 267 
Table I.5 – GSM AMR Capability Parameter – GSM EFR comfort noise ...................................... 267 
Table I.6 – GSM AMR Capability Parameter – IS-641 comfort noise ............................................ 267 
Table I.7 – GSM AMR Capability Parameter – PDC EFR comfort noise....................................... 267 
Table I.8 – Number of speech bits in different AMR modes ........................................................... 268 
Table I.9 – Example, mapping of the AMR speech coding mode 6.7 kbit/s ................................... 269 
Table I.10 – Mapping of the AMR speech coding modes defined in GSM 06.90 to mode index bits in 
transmitted octets ............................................................................................................................. 269 
Table I.11 – Mapping of Comfort Noise descriptor bits from  GSM 06.92 to octets for the mode index 
8  (Bits from s1 to s35 refer to GSM 06.92) .................................................................................... 269 
Table I.12 – Mapping of silence insertion descriptor bits from GSM 06.60  (parameters also described 
in GSM 06.62) to octets for the Mode Index 9  (Bits from s1 to s91 refer to GSM 06.60) ............. 270 
Table I.13 – Mapping of silence insertion descriptor bits from TIA IS-641-A to octets, for the mode 
index 10 (Bits from cn0 to cn37 refer to TIA IS-641-A) ................................................................. 271 
Table I.14 – Mapping of silence insertion descriptor bits from  RCR STD-27H to octets for the mode 
index 11  (Bits from s1 to s35 refer to RCR STD-27H) .................................................................. 271 
Table I.15 – Definition of the no transmission frame for the mode index 15 .................................. 272 
Table I.16 – Subjective importance of the speech-encoded bits for AMR12.2 ............................... 272 
Table I.17 – Subjective importance of the speech-encoded bits for AMR10.2 ............................... 273 

 
    Rec. ITU-T H.245 (03/2022)  xv 
  Page 
Table I.18 – Subjective importance of the speech-encoded bits for AMR7.95 ............................... 273 
Table I.19 – Subjective importance of the speech-encoded bits for AMR7.4 ................................. 274 
Table I.20 – Subjective importance of the speech-encoded bits for AMR6.7 ................................. 274 
Table I.21 – Subjective importance of the speech-encoded bits for AMR5.9 ................................. 275 
Table I.22 – Subjective importance of the speech-encoded bits for AMR5.15 ............................... 275 
Table I.23 – Subjective importance of the speech-encoded bits for AMR4.75 ............................... 275 
Table J.1 – TIA/EIA 136 ACELP Capability Identifier .................................................................. 276 
Table J.2 – TIA/EIA 136 ACELP Capability Parameter – maxAl-sduAudioFrames ...................... 276 
Table J.3 – TIA/EIA 136 ACELP Capability Parameter – Comfort Noise ..................................... 276 
Table J.4 – TIA/EIA 136 ACELP Capability Parameter – Scrambled ............................................ 277 
Table K.1 – TIA/EIA 136 US1 Capability Identifier ....................................................................... 278 
Table K.2 – TIA/EIA 136 US1 Capability Parameter – maxAl-sduAudioFrames .......................... 278 
Table K.3 – TIA/EIA 136 US1 Capability Parameter – Comfort Noise ......................................... 278 
Table K.4 – TIA/EIA 136 US1 Capability Parameter – Scrambled ................................................ 279 
Table L.1 – CDMA EVRC Capability Identifier ............................................................................. 280 
Table L.2 – TIA/EIA IS-127 CDMA EVRC Capability Parameter –  maxAl-sduAudioFrames .... 280 
Table L.3 – CDMA EVRC Capability Parameter – EVRC Bit-Rate............................................... 280 
Table L.4 – CDMA EVRC Capability Parameter – Scrambled ....................................................... 281 
Table M.1 – ISO/IEC 13818-7 Capability Identifier ....................................................................... 282 
Table M.2 – Profile and Level for ISO/IEC 13818-7 Capability ..................................................... 282 
Table M.3 – ITU-R BS.1196-2 Capability Identifier ....................................................................... 282 
Table N.1 – IETF RFC 3389 Comfort Noise ................................................................................... 283 
Table O.1 – L16 Capability Identifier .............................................................................................. 284 
Table O.2 – L16 Capability Parameter – channels........................................................................... 284 
Table P.1 – Capability Identifier for bounded audio stream ............................................................ 285 
Table P.2 – Minimum packet size parameter ................................................................................... 285 
Table P.3 – Audio capability ............................................................................................................ 285 
Table Q.1 – N  64 Capability Identifier ......................................................................................... 287 
Table Q.2 – N  64 Number-of-Channels Parameter ....................................................................... 287 
Table Q.3 – N  64 Payload Size Parameter .................................................................................... 287 
Table R.1 – Capability Identifier for GSM AMR-NB Capability ................................................... 290 
Table R.2 – Capability Identifier for GSM AMR-WB Capability ................................................... 290 
Table R.3 – GSM AMR Capability Parameter – octetAlign............................................................ 291 
Table R.4 – GSM AMR Capability Parameter – modeSet .............................................................. 291 
Table R.5 – GSM AMR Capability Parameter – modeSetExtended ............................................... 292 

 
xvi  Rec. ITU-T H.245 (03/2022) 
  Page 
Table R.6 – GSM AMR Capability Parameter – modeChangePeriod ............................................. 292 
Table R.7 – GSM AMR Capability Parameter – modeChangeAny ................................................ 293 
Table R.8 – GSM AMR Capability Parameter – AlSduAudioFrames ............................................ 293 
Table R.9 – GSM AMR Capability Parameter – Interleaving ......................................................... 293 
Table R.10 – GSM AMR Capability Parameter – numChannels .................................................... 294 
Table S.1 – Capability Identifier for iLBC Capability ..................................................................... 295 
Table S.2 – iLBC Capability Parameter – MaxFramesPerPacket .................................................... 295 
Table S.3 – iLBC Capability Parameter – Mode ............................................................................. 296 
Table T.1 – DynamicPayloadType Replacement Capability ........................................................... 297 
Table V.1 – Identifier for IPProtocol Support ................................................................................. 301 
Table V.2 –Transport Support Parameter ........................................................................................ 301 
Table II.2-1 – Master-slave determination shortened names ........................................................... 306 
Table III.1 – Procedure timers ......................................................................................................... 322 
Table III.2 – Procedure counters ...................................................................................................... 323 
Table VI.1 – Enhancement Layer ITU-T H.245 parameter setting examples ................................. 328 
Table VI.2 – H263Capability setting examples for OpenLogicalChannel messages ...................... 331 
Table VI.3 – H263Capability setting examples for OpenLogicalChannel messages ...................... 333 
Table VII.1 – Capability Identifier Template................................................................................... 335 
Table VII.2 – Capability Patrameter Template ................................................................................ 335 
Table VII.3 – Example ITU-T H.261 Capability Identifier ............................................................. 336 
Table VII.4 – Example ITU-T H.261 Capability Parameter – qcifMPI .......................................... 336 
Table VII.5 – Example ITU-T H.261 Capability Parameter – cifMPI ............................................ 337 
Table VII.6 – Example ITU-T H.261 Capability Parameter – temporalSpatialTradeOffCapability337 
Table VII.7 – Example ITU-T H.261 Capability Parameter –  stillImageTransmision ................... 337 
Table VIII.1 – List of generic capabilities defined in Recommendations/ Standards other than this 
Recommendation .............................................................................................................................. 338 
Table  VIII.2  –  List  of  generic  messages  defined  in  Recommendations/Standards  other  than  this 
Recommendation .............................................................................................................................. 341 
 
 
List of Figures 
  Page 
Figure C.1 – SDL key ...................................................................................................................... 156 
Figure C.2 – State transition diagram for sequence of primitives at MSDSE ................................. 160 
Figure C.3 – Primitives and messages in the MSDSE ..................................................................... 161 
Figure C.4 – MSDSE SDL (sheet 1 of 5) ......................................................................................... 163 

 
    Rec. ITU-T H.245 (03/2022)  xvii 
  Page 
Figure C.4 – MSDSE SDL (sheet 2 of 5) ......................................................................................... 164 
Figure C.4 – MSDSE SDL (sheet 3 of 5) ......................................................................................... 165 
Figure C.4 – MSDSE SDL (sheet 4 of 5) ......................................................................................... 166 
Figure C.4 – MSDSE SDL (sheet 5 of 5) ......................................................................................... 167 
Figure C.5 – State transition diagram for sequence of primitives at outgoing CESE ...................... 170 
Figure C.6 – State transition diagram for sequence of primitives at incoming CESE ..................... 170 
Figure C.7 – Primitives and messages in the Capability Exchange Signalling Entity ..................... 171 
Figure C.8 – Outgoing CESE SDL (sheet 1 of 2) ............................................................................ 173 
Figure C.8 – Outgoing CESE SDL (sheet 2 of 2) ............................................................................ 174 
Figure C.9 – Incoming CESE SDL (sheet 1 of 2) ............................................................................ 174 
Figure C.9 – Incoming CESE SDL (sheet 2 of 2) ............................................................................ 175 
Figure C.10 – State transition diagram for sequence of  primitives at outgoing LCSE ................... 179 
Figure C.11 – State transition diagram for sequence of  primitives at incoming LCSE .................. 180 
Figure C.12 – Primitives and messages in the  Logical Channel Signalling Entity ......................... 181 
Figure C.13 – Outgoing LCSE SDL (sheet 1 of 4) .......................................................................... 183 
Figure C.13 – Outgoing LCSE SDL (sheet 2 of 4) .......................................................................... 184 
Figure C.13 – Outgoing LCSE SDL (sheet 3 of 4) .......................................................................... 185 
Figure C.14 – Incoming LCSE SDL (sheet 1 of 3) .......................................................................... 187 
Figure C.14 – Incoming LCSE SDL (sheet 2 of 3) .......................................................................... 187 
Figure C.14 – Incoming LCSE SDL (sheet 3 of 3) .......................................................................... 188 
Figure C.15 – State transition diagram for sequence of  primitives at outgoing B-LCSE ............... 193 
Figure C.16 – State transition diagram for sequence of  primitives at incoming B-LCSE .............. 193 
Figure C.17 – Primitives and messages in the bidirectional  Logical Channel Signalling Entity ... 195 
Figure C.18 – Outgoing B-LCSE SDL (sheet 1 of 4) ...................................................................... 197 
Figure C.18 – Outgoing B-LCSE SDL (sheet 2 of 4) ...................................................................... 198 
Figure C.18 – Outgoing B-LCSE SDL (sheet 3 of 4) ...................................................................... 199 
Figure C.18 – Outgoing B-LCSE SDL (sheet 4 of 4) ...................................................................... 199 
Figure C.19 – Incoming B-LCSE SDL (sheet 1 of 4) ...................................................................... 200 
Figure C.19 – Incoming B-LCSE SDL (sheet 2 of 4) ...................................................................... 201 
Figure C.19 – Incoming B-LCSE SDL (sheet 3 of 4) ...................................................................... 202 
Figure C.19 – Incoming B-LCSE SDL (sheet 4 of 4) ...................................................................... 202 
Figure C.20 – State transition diagram for sequence of  primitives at outgoing CLCSE ................ 205 
Figure C.21 – State transition diagram for sequence of  primitives at incoming CLCSE ............... 205 
Figure C.22 – Primitives and messages in the Close  Logical Channel Signalling Entity............... 206 
Figure C.23 – Outgoing CLCSE SDL (sheet 1 of 2) ........................................................................ 207 

 
xviii  Rec. ITU-T H.245 (03/2022) 
  Page 
Figure C.23 – Outgoing CLCSE SDL (sheet 2 of 2) ........................................................................ 208 
Figure C.24 – Incoming CLCSE SDL (sheet 1 of 2) ....................................................................... 208 
Figure C.24 – Incoming CLCSE SDL (sheet 2 of 2) ....................................................................... 209 
Figure C.25 – State transition diagram for sequence of  primitives at outgoing MTSE .................. 212 
Figure C.26 – State transition diagram for sequence of  primitives at incoming MTSE ................. 212 
Figure C.27 – Primitives and messages in the Multiplex Table Signalling Entity .......................... 214 
Figure C.28 – Outgoing MTSE SDL (sheet 1 of 3) ......................................................................... 216 
Figure C.28 – Outgoing MTSE SDL (sheet 2 of 3) ......................................................................... 217 
Figure C.28 – Outgoing MTSE SDL (sheet 3 of 3) ......................................................................... 218 
Figure C.29 – Incoming MTSE SDL (sheet 1 of 2) ......................................................................... 219 
Figure C.29 – Incoming MTSE SDL (sheet 2 of 2) ......................................................................... 220 
Figure C.30 – State transition diagram for sequence of primitives at outgoing RMESE ................ 222 
Figure C.31 – State transition diagram for sequence of primitives at incoming RMESE ............... 222 
Figure C.32 – Primitives and messages in the Request Multiplex Entry Signalling Entity ............. 224 
Figure C.33 – Outgoing RMESE SDL (sheet 1 of 2) ....................................................................... 225 
Figure C.33 – Outgoing RMESE SDL (sheet 2 of 2) ....................................................................... 225 
Figure C.34 – Incoming RMESE SDL (sheet 1 of 2) ...................................................................... 226 
Figure C.34 – Incoming RMESE SDL (sheet 2 of 2) ...................................................................... 226 
Figure C.35 – State transition diagram for sequence of  primitives at outgoing MRSE .................. 230 
Figure C.36 – State transition diagram for sequence of  primitives at incoming MRSE ................. 230 
Figure C.37 – Primitives and messages in the Mode  Request Signalling Entity ............................ 231 
Figure C.38 – Outgoing MRSE SDL (sheet 1 of 3) ......................................................................... 232 
Figure C.38 – Outgoing MRSE SDL (sheet 2 of 3) ......................................................................... 233 
Figure C.38 – Outgoing MRSE SDL (sheet 3 of 3) ......................................................................... 234 
Figure C.39 – Incoming MRSE SDL (sheet 1 of 2) ......................................................................... 235 
Figure C.39 – Incoming MRSE SDL (sheet 2 of 2) ......................................................................... 235 
Figure C.40 – State transition diagram for sequence of primitives at RTDSE ................................ 237 
Figure C.41 – Primitives and messages in the RTDSE .................................................................... 238 
Figure C.42 – RTDSE SDL (sheet 1 of 2) ....................................................................................... 239 
Figure C.42 – RTDSE SDL (sheet 2 of 2) ....................................................................................... 240 
Figure C.43 – State transition diagram for sequence of  primitives at outgoing MLSE .................. 243 
Figure C.44 – State transition diagram for sequence of  primitives at incoming MLSE ................. 243 
Figure C.45 – Primitives and messages in the Maintenance Loop Signalling Entity ...................... 245 
Figure C.46 – Outgoing MLSE SDL (sheet 1 of 3) ......................................................................... 246 
Figure C.46 – Outgoing MLSE SDL (sheet 2 of 3) ......................................................................... 247 