int sm_vmprx_config_jitter(struct sm_vmprx_jitter_parms *jitterp)
typedef struct sm_vmprx_jitter_parms {
tSMVMPrxId vmprx; /* in */
tSM_UT32 max_delay_ms; /* in */
tSM_UT32 initial_delay_ms; /* in */
} SM_VMPRX_JITTER_PARMS;
Allows an application to confgure the jitter buffer belonging to a VMP[rx]. Default values are used for the jitter buffer when a VMP[rx] is created, so explicit configuration may not be necesary. Reconfiguration of the jitter buffer may result in audible artifacts in the audio stream during reconfiguration.
It is generally considered that the total end-to-end delay must be no more than about 150 milliseconds for acceptable usability. Unavoidable delay comes from two main sources: packetisation delay and propagation delay. A codec causes packetisation delay, for example, the G.711 codec sending packets each containing 20 mS of data must add 20 mS of delay. Propagation delay obviously varies with the distance covered, with the longest Earthbound link (halfway around the world) taking at least 67 mS, as limited by the speed of light. In practice, delays of about 10 to 25 mS can be found within the U.S.A., with international delays being longer (e.g. U.S.A. to U.K. about 50 to 60 mS). This means that the jitter buffer should generally be limited to 100 mS, with a smaller value used for long-distance calls or when using codecs which impose a longer packetisation delay..
0 if call completed successfully, otherwise a standard error such as:
This function is part of the Prosody RTP processing API.