Prosody RTP processing: API: sm_vmptx_config_codec_ilbc

Prototype Definition

int sm_vmptx_config_codec_ilbc(struct sm_vmptx_codec_ilbc_parms *codecp)

Parameters

*codecp
a structure of the following type: 
typedef struct sm_vmptx_codec_ilbc_parms {
	tSMVMPtxId vmptx;					/* in */
	tSM_INT payload_type;					/* in */
	tSM_INT frame_len;					/* in */
	enum kSMVMPTxVADMode VADMode;				/* in */
	tSM_INT frames_per_packet;				/* in */
} SM_VMPTX_CODEC_ILBC_PARMS;

Description

Configures a VMP[tx] to use iLBC for encoding data.

This requires the module ilbc to have been downloaded.

Fields

vmptx
The VMP[tx] to which to add this codec
payload_type
The payload type identifer to use with this codec (see IETF RFC 3550 section 13). Supplying a value of -1 will remove any payload type configuration from the codec preventing its use.
frame_len
The number of milliseconds of audio to encode in each frame. This must be either 20 or 30. This value multiplied by frames_per_packet gives the total length of each packet.
VADMode
The mode of operation for the voice activity detector One of these values:
kSMVMPTxVADModeDisabled
Disable VAD - all data delivered to the VMP[tx] is encoded and sent
kSMVMPTxVADModeEnabled
Enable VAD - if the signal is inactive, no data is sent (DTX)
kSMVMPTxVADModeComfortNoise
Enable VAD with comfort noise generation - if the signal is inactive, comfort noise packets are sent. If the main codec does not define its own comfort noise, it must have been configured by sm_vmptx_config_codec_comfort_noise().
frames_per_packet
The number of frames to send per packet. This value is normally one but larger values can be used, reducing the packet overhead at the expense of extra delay. This value multiplied by frame_len gives the total length of each packet.

Returns

0 if call completed successfully, otherwise a standard error such as:

This function is part of the Prosody RTP processing API.