Editing Lip sync (section)

==Television transmission synchronization==
{{Main|Audio to video synchronization}}
An example of a lip synchronization problem, also known as [[lip sync error]] is the case in which [[television]] video and audio signals are transported via different facilities (''e.g.,'' a [[geosynchronous satellite]] radio link and a landline) that have significantly different [[Propagation delay|delay]] times. In such cases, it is necessary to delay the earlier of the two signals electronically.

Lip sync issues have become a serious problem for the television industry worldwide. Lip sync problems are not only annoying but can lead to subconscious viewer stress which in turn leads to viewer dislike of the television program they are watching.<ref>[http://www.curtpalme.com/docs/EffectsOfAudioVideoAsynchrony.pdf ''"Effects of Audio-Video Asynchrony on Viewer's Memory, Evaluation of Content and Detection Ability"''] by Reeves and Voelker.</ref> Television industry standards organizations have become involved in setting standards for lip sync errors.<ref>{{citation|title=IS-191: Relative Timing of Sound and Vision for Broadcast Operations |publisher=[[ATSC]] |date=2003-06-26 |url=http://www.atsc.org/cms/index.php/standards/document-download/doc_download/47-is-191-relative-timing-of-sound-and-vision-for-broadcast-operations |archive-url=https://web.archive.org/web/20120321084955/http://www.atsc.org/cms/index.php/standards/document-download/doc_download/47-is-191-relative-timing-of-sound-and-vision-for-broadcast-operations |archive-date=2012-03-21 |url-status=dead }}</ref> In 2015 SMPTE (the Society of Motion Picture and Television Engineers) adopted Standard [https://web.archive.org/web/20180310074411/http://ieeexplore.ieee.org/search/searchresult.jsp?newsearch=true&queryText=SMPTE%20ST2064 ST2064] which provides technology for greatly reducing or eliminating lip sync errors in television programming.