2.11.7 definitions of "timebase", "continuous scale, "relative time units" (Action-699, Action-644)

2.11.7 definitions of "timebase", "continuous scale, "relative time units" (Action-699, Action-644)

Timebase:

Defines a common time scale for a time-based media presentation.

Continuous scale:

When interacting with a time-based media presentation, a continuous scale allows user (or programmatic) action to set the active
playback position to any time point on the presentation timeline. The granularity of the positioning is determined by the smallest
resolvable time unit in the media timebase.

Relative time units

When interacting with a time-based media presentation, a user may find it easier to move forward or backward via
time intervals, such as skipping ahead by 10 seconds in a video lecture.  Relative time units define time intervals for media navigation
which may be preset, user configurable, and/or automatically calculated based upon media duration.