Dialogic 05-2548-006 manual Dialogic IP Media Library API Programming Guide

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ipmMediaInfo.MediaData[unCount].eMediaType = MEDIATYPE_AUDIO_REMOTE_CODER_OPTIONS_INFO; ipmMediaInfo.MediaData[unCount].mediaInfo.AudioCoderOptionsInfo.unVersion =

IPM_AUDIO_CODER_OPTIONS_INFO_VERSION; ipmMediaInfo.MediaData[unCount].mediaInfo.AudioCoderOptionsInfo.unCoderOptions =

CODER_OPT_SIGNALING_OFF; ipmMediaInfo.MediaData[unCount].mediaInfo.AudioCoderOptionsInfo.unParm1 =

CODER_OPT_INTERLEAVE_LENGTH; ipmMediaInfo.MediaData[unCount].mediaInfo.AudioCoderOptionsInfo.nValue1 = 6; ipmMediaInfo.MediaData[unCount].mediaInfo.AudioCoderOptionsInfo.unParm2 = 0; ipmMediaInfo.MediaData[unCount].mediaInfo.AudioCoderOptionsInfo.nValue2 = 0;

unCount++;

ipmMediaInfo.unCount = unCount;

3.3.9Dialogic® IP Media Library API Programming Guide

Using AMR coders for narrow band audio and using enhanced variable rate codecs The following information, which is applicable to the ATCA Multimedia Platform, should be added to the programming guide, possibly as a new chapter.

Using AMR Coders for Narrow Band Audio

Description

AMR is an adaptive multi-rate speech codec. During operation, both local and remote sides can request a change in the bit rate and dynamically adjust the bandwidth. The protocol uses the following:

•A Frame Type (FT) to indicate the transmitted bit rate

•A Codec Mode Request (CMR) value to request a particular bit rate in every packet

To control the bit rate, AMR assumes that all connections are bi-directional.

This feature is specific to AMR-NB and excludes support for AMR-WB and AMR-WB+, which support wideband audio and some other formats not addressed by AMR.

The codec supports the following bit rates:

•12.2 kbit/s (GSM EFR)

•10.2 kbit/s

•7.95 kbit/s

•7.40 kbit/s (IS-641)

•6.70 kbit/s (PDC-EFR)

•5.90 kbit/s

•5.15 kbit/s

•4.75 kbit/s

•1.80 kbit/s (assuming SID frames are continuously transmitted)

Note: The 1.80 kbit/s rate is not actually a voice signal, but the bit rate consumed when Voice Activation Detection (VAD) is processing a silence.

32Dialogic® Multimedia Software for ATCA Release 1.0 Release Update, Rev 06 — January 23, 2008 Dialogic Corporation

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Contents Release Update Dialogic Multimedia Software for AdvancedTCA ReleaseDialogic Corporation Intended Audience How to Use This PublicationPurpose Related Information See the following for additional informationDocument Rev 04 published June 8 Document Rev 06 published January 23Document Rev 05 published June 22 Document Rev 03 published May 1 Document Rev 02 published March 30Document Rev 01 published January Initial version of documentRelease Developments Summary of Features Updates to IpmaudiocoderinfoUpdates to Ipmaudiocoderoptionsinfo 2Release.Issues2 Issues Sorted by Type, Dialogic Multimedia Platform CLIAs the clock source instead of a previously recovered Dlservices cli start MsmlIpml PARMCHRFC2833EVTRXPLTCLI, Snmp EvrcRtfConfigLinux.xml for mediasvr Existent list when the cable is unplugged from a Pstn Issue Type Defect No Product or Description 3Documentation.Updates3 Dialogic Conferencing CNF API Library Reference Dialogic Conferencing CNF API Programming GuideDialogic Device Management API Library Reference Dialogic Fax Software ReferenceDialogic Global Call IP Technology Guide Dialogic IP Media Library API Library ReferenceUpdates to the ipmSetParm and ipmGetParm functions ParmchlatencyalgaudioParmchlatencyframeinitaudio ParmchlatencyframemaxaudioUpdate to , Events Codertypeamrnbnone CodertypeevrcPage IpmGetCapabilities „ Description„ Cautions „ Example Ipmaudiocoderoptionsinfo „ Example Using AMR Coders for Narrow Band Audio Description Dialogic IP Media Library API Programming GuideDialogic IP Media Library API Support Supported RTP Payload FormatLocal Side Remote Side ExampleIpmaudiocoderoptionsinfoversion Local Side Remote Side Using Enhanced Variable Rate Codecs Coderoptamrcmrlimit CoderoptamrefficientResource Reservation of Audio Coders Outbound CallInbound Call Implicit Release by a Subsequent Successful Reserve CallHandling a Resource Reservation Failure Application issues call to release resource RESOURCEIPMG726 Dialogic Multimedia API Library Reference Dialogic Multimedia API Programming GuideDialogic Standard Runtime Library API Library Reference Dialogic Standard Runtime Library API Programming GuideDialogic Voice API Library Reference Dialogic Voice API Programming Guide
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