Editing Jitter (section)

===Jitter buffers===
Jitter buffers or de-jitter buffers are [[Buffer (telecommunication)|buffers]] used to counter jitter introduced by queuing in [[packet switching|packet-switched networks]] to ensure continuous playout of an audio or video [[media stream]] transmitted over the network.<ref>{{Cite web |url=http://searchenterprisevoice.techtarget.com/sDefinition/0,,sid66_gci906844,00.html |title=Jitter Buffer |access-date=2006-04-03 |archive-date=2006-05-07 |archive-url=https://web.archive.org/web/20060507172221/http://searchenterprisevoice.techtarget.com/sDefinition/0,,sid66_gci906844,00.html |url-status=dead }}</ref>  The maximum jitter that can be countered by a de-jitter buffer is equal to the buffering delay introduced before starting the play-out of the media stream. In the context of packet-switched networks, the term ''[[packet delay variation]]'' is often preferred over ''jitter''.

Some systems use sophisticated delay-optimal de-jitter buffers that are capable of adapting the buffering delay to changing network characteristics. The adaptation logic is based on the jitter estimates computed from the arrival characteristics of the media packets. Adjustments associated with adaptive de-jittering involves introducing discontinuities in the media play-out which may be noticeable to the listener or viewer. Adaptive de-jittering is usually carried out for audio play-outs that include [[voice activity detection]] that allows the lengths of the silence periods to be adjusted, thus minimizing the perceptual impact of the adaptation.