A RepeatTime represents a r= field contained within a TimeDescription.
A RepeatTime specifies the repeat times for a SessionDescription.
This consists of a "repeat interval", an "active duration", and a list of offsets relative to the t=
start-time (see Time.getStart()).
Quoting from RFC 2327:
For example, if a session is active at 10am on Monday and 11am on Tuesday for
one hour each week for three months, then the <start time> in the corresponding
"t=" field would be the NTP representation of 10am on the first Monday, the
<repeat interval> would be 1 week, the <active duration> would be 1 hour, and
the offsets would be zero and 25 hours. The corresponding "t=" field stop time
would be the NTP representation of the end of the last session three months later.
By default all fields are in seconds, so the "r=" and "t=" fields might be:
r=604800 3600 0 90000
Please refer to IETF RFC 2327 for a description of SDP.