Introduction

CNF.CONFERENCE

Dependent Function

cnfCreateConference

CNF.CONFERENCE_ATTR

Dependent Function

cnfSetConferenceAttribute

CNF.MEMBER

Dependent Function

cnfJoinConference

CNF.MEMBER_ATTR

Dependent Functions

CNF.TONE

Dependent Function

cnfStartTone

Introduction

The behavior of some NaturalConference functions is defined by multiple parameters. These parameters are grouped together into structures for convenience and efficiency. Each parameter structure has a default value that is compatible with many configurations. The parameters can be modified to

• Enable or disable function features.

• Adapt a function for exceptional configurations.

The following sections list and describe the parameters. The dependent functions are also specified.

CNF.CONFERENCE

Dependent Function

cnfCreateConference

Field Name	Type	Default	Units	Description
flags	DWORD	0	Mask	Flag to disable conferencing resource capabilities. See values of CNF_NO_XXX keywords defined in the cnfdef.h header file.
allocated_members	DWORD	0	Member	Number of members to allocate on the conferencing resource when creating a conference. Valid range is 0 to 62.
user_value	DWORD	0		User defined value.

CNF.CONFERENCE_ATTR

Dependent Function

cnfSetConferenceAttribute

Field Name	Type	Default	Units	Description
num_loudest	DWORD	3	Member	Number of members selected for building the conference's output signal. Valid range is 1 to 62. Recommended values are 3 to 5.
event_mask	DWORD	0	Mask	Mask used to determine which events are generated by NaturalConference for that conference.
active_talkers	DWORD	3	Member	Number of members retained for building the list of active talkers and generating CNFEVN_ACTIVE_TALKERS_ CHANGE if a change occurs. Valid range is 1 to 62. Recommended values are 3 to 5.
active_talkers_ timer	DWORD	1000	ms	Time NaturalConference waits between sending two CNFEVN_ACTIVE_TALKERS_ CHANGE events. Valid range is 100 to 60000.

CNF.MEMBER

Dependent Function

cnfJoinConference

Field Name	Type	Default	Units	Description
user_value	DWORD	0	Integer	A user defined value.

CNF.MEMBER_ATTR

Dependent Functions

• cnfSetMemberAttribute

• cnfGetMemberAttributeList

  Field Name	Type	Default	Units	Description
  ec_enabled	DWORD	1	Boolean	Flag to enable echo cancellation capability on the input signal. Set to 1 to enable EC and 0 to disable it.
  ec_gain	INT32	0	dB	Amount of amplification input applied to echo-cancelled output. Valid automatic gain range is -54 to +24.
  ec_predelay	DWORD	0	ms	Output sample delay. Valid automatic gain range is 0 to 9.
  input_agc_enable	DWORD	1	Boolean	Flag to enable automatic gain control on the input signal. Set to 1 to enable AGC and 0 to disable it.
  input_agc_targetampl	INT32	-19	dBm	Target amplitude for AGC. Valid range is -45 to 0.
  input_agc_silenceampl	INT32	-40	dBm	Noise threshold for AGC. Gain adjustment is suspended for signals below this level. Valid range is -45 to 0.
  input_gain	INT32	0	dB	Gain applied to the signal before it is encoded. If AGC is enabled, this is the initial gain. Valid automatic gain range is -12 to +12.
  input_law	DWORD	0	Integer	G. 711 law to be applied in the member's input. Valid range is 0 to 2.
  output_agc_enable	DWORD	1	Boolean	Flag to enable automatic gain control on the output signal. Set to 1 to enable AGC and 0 to disable.
  output_agc_targetampl	INT32	-19	dBm	Target amplitude for output AGC. Valid range is -45 to 0.
  output_agc_silenceampl	INT32	-40	dBm	Noise threshold for output AGC. Gain adjustment is suspended for signals below this level. Valid range is -45 to 0.
  output_gain	INT32	0	dB	Gain applied to the encoded audio. If output AGC is enabled, this is the initial gain. Valid automatic gain range is -12 to +12.
  output_law	DWORD	0	Integer	G. 711 law to be applied in the member's output. Valid range is 0 to 2.
  self_echo_enable	DWORD	0	Boolean	Indicates if the voice received from this member on its input is mixed and returned to that member on its output. This attribute can be enabled when the output is not connected to the member, but is actually used for recording. Set to 1 to enable and 0 to disable.
  talker_enable	DWORD	0	Boolean	Flag to enable the member as talker. Set to 1 to enable and 0 to disable.
  listener_enable	DWORD	1	Boolean	Flag to enable the member as listener. Set to 1 to enable and 0 to disable.
  talker_privilege	DWORD	0	Boolean	Flag to enable the member as privileged talker. Set to 1 to enable and 0 to disable.
  dtmf_clamping_enable	DWORD	1	Boolean	Flag to enable the DTMF clamping capability. Set to 1 to enable and 0 to disable.
  dtmf_clamping_delay_ line	DWORD	28	ms	Delay line to bufferize the signal received by each member before removing the DTMF with the DTMF clamping module. Valid range is 0 to 28 ms.
  tone_clamping_enable	DWORD	1	Boolean	Flag to enable the tone clamping capability. Set to 1 to enable and 0 to disable.

CNF.TONE

Dependent Function

cnfStartTone

Field Name	Type	Default	Units	Description
freq1	DWORD	1000	Hz	First (or only) frequency of the generated tone. Valid range is 200 to 3600.
ampl1	INT32	-20	dBm	Amplitude of the first (or only) frequency component. Valid range is -54 to 3.
freq2	DWORD	0	Hz	Second frequency of the generated tone, or 0 if the tone is a single frequency. If not 0, valid range is 200 to 3600.
ampl2	INT32	0	dBm	Amplitude of the second frequency component, if any. Valid range is -54 to 3.
ontime	DWORD	200	ms	Duration of the tone. Valid range is 1 to 65535.
offtime	DWORD	0	ms	Duration of silence between tones. Specify 0 for no off time. Valid range is 0 to 65535.
iterations	INT32	1	integer	Number of times to repeat the alternating tone and silence period. A count of -1 means repeat forever. Otherwise the valid range is 1 to 32767.