(1) The number of beats/amount of time a sample ends after the playback-endstop ping marker.
(2) In SMPTE timecode synchronization for videotape post-production, thea number of seconds and/or frames specified which are automatically added to any timecodetime code address subsequently specified as a record-out point. Thus, when inserting dialog or music, on each take master and slave machines will continue to roll for the post-roll duration after recording is stopped. This prevents the type of wow that occurs when a transport is stopped while the electronics are still recording. Some brands of synchronizer add the post-roll to the mark-out rather than the record-out location.