An experimental delay analysis for local audio video streams for desktop collaborations
The delay which is one of the QoS (quality of service) parameters is considered to be a crucial factor for the effective usage of realtime audio and video streams in the interactive collaborations. Among the various causes of the delay, we, in this paper, focus on the local delay concerned with the schemes which handle continuous inflow of encoded data from constant or variable bit-rate audio and video encoders. We introduce two implementation approaches, Pull Model and Push Model. While the pull model periodically pumps out the incoming data from the system buffer, the push model receives events from the device drivers for hardware encoders. From our experiments, it was shown that the push model outperforms the other for both variable and constant bit rate in terms of the local delay, when the system suffers reasonable loads.
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