Dialogic Global Call IP Benutzerhandbuch
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Dialogic
®
Global Call IP Technology Guide — November 2007
Dialogic Corporation
IP-Specific Operations
gc_AcceptCall( ) to get maximum benefit from Global Call’s early media support. Capability
types can be GCCAPTYPE_AUDIO and/or GCCAPTYPE_RDATA. The session capabilities that
can result when different capabilities are set by applications are listed in the Table 3.
types can be GCCAPTYPE_AUDIO and/or GCCAPTYPE_RDATA. The session capabilities that
can result when different capabilities are set by applications are listed in the Table 3.
4.3.2.2
Resource Allocation When Using Low-Bit Rate Coders
The number of resources available when using G.723 and G.729 coders is limited. When all
resources are consumed, depending on the requirements of the application, different behavior may
be observed as follows:
resources are consumed, depending on the requirements of the application, different behavior may
be observed as follows:
•
If the application specifies only G.723 and/or G.729 audio coders before gc_MakeCall( ),
gc_CallAck( ), gc_AcceptCall( ), or gc_AnswerCall( ), the result is a function failure with an
error code of IPERR_TXRXRESOURCESINSUFF.
gc_CallAck( ), gc_AcceptCall( ), or gc_AnswerCall( ), the result is a function failure with an
error code of IPERR_TXRXRESOURCESINSUFF.
•
If the application specifies G.711 with G.723 and/or G.729 audio coders, only the G.711 coder
will be provided in the capability set sent to the remote endpoint.
will be provided in the capability set sent to the remote endpoint.
•
If the application does not explicitly specify any audio capability, then the G.711 coders (both
A-law and
A-law and
μ-law) are included in the capability set sent to the remote endpoint.
LBR coder resources are only released when gc_ReleaseCallEx( ) is used, regardless of whether
the resource was negotiated or not.
the resource was negotiated or not.
Note:
When using low bit-rate (LBR) coders, in-band transmission of DTMF tones will not work reliably
and should not be attempted.
and should not be attempted.
4.3.3
Specifying Nonstandard Data Information (H.323)
To specify Nonstandard Data information to be included in the H.323 SETUP message, use the
gc_SetUserInfo( ) function with a duration parameter of GC_SINGLECALL to preset the
information. If the duration parameter is set to GC_ALLCALLS, the function fails.
gc_SetUserInfo( ) function with a duration parameter of GC_SINGLECALL to preset the
information. If the duration parameter is set to GC_ALLCALLS, the function fails.
To specify Nonstandard Data, the GC_PARM_BLK pointed by the infoparmblkp parameter in the
function call must be contain two parameter elements that use the IPSET_NONSTANDARDDATA
function call must be contain two parameter elements that use the IPSET_NONSTANDARDDATA
Table 3. Capabilities Set by Application
GCCAPTYPE_AUDIO
capability set by application
GCCAPTYPE_RDATA
capability set by application
Resulting Capability
for Initial Connection
Not set
Not set
Any supported audio capability or T.38 fax.
One or more
GCCAP_AUDIO_XXX
GCCAP_AUDIO_XXX
Not Set
Any specified audio capability.
No T.38 fax.
No T.38 fax.
Not Set
GCCAP_DATA_t38UDPFax
T.38 fax only.
No audio cpability.
No audio cpability.
One or more
GCCAP_AUDIO_XXX
GCCAP_AUDIO_XXX
GCCAP_DATA_t38UDPFax
Any specified audio capability or T.38 fax.
GCCAP_dontCare
Not Set
Any supported audio capability.
No T.38 fax.
No T.38 fax.
GCCAP_dontCare GCCAP_DATA_t38UDPFax
Any
supported audio capability or T.38 fax.