In a static presentation, the first period SHALL start at the zero point of the MPD timeline (with a
Period@start value of 0 seconds).
When Period@start is absent, the start is derived from the sum of the
preceding periods' Period@duration values, per the PeriodStart derivation
in ISO/IEC 23009-1 ยง5.3.2.1. This is common in on-demand manifests that
declare only per-period durations (no explicit @start, no
MPD@mediaPresentationDuration).
Calculates the start time of the given period.
In a static presentation, the first period SHALL start at the zero point of the MPD timeline (with a Period@start value of 0 seconds).
When
Period@startis absent, the start is derived from the sum of the preceding periods'Period@durationvalues, per the PeriodStart derivation in ISO/IEC 23009-1 ยง5.3.2.1. This is common in on-demand manifests that declare only per-period durations (no explicit@start, noMPD@mediaPresentationDuration).