duration
set duration <min>-<max>
This setting configures the minimum and maximum length (in minutes) that an episode is expected to be. This is used when the automap command is mapping titles to episodes, to determine which titles on the disc are likely to be episodes.
Typically, if episodes are expected to be half an hour long (for example), you may find that they are actually somewhere in the region of 28 to 30 minutes where the slack time was filled in broadcasts by advertising or filler segments. Occasionally (for special episodes, such as finalés) episodes may be a few minutes longer than the expected runtime. Thus, when setting the duration, you usually want to err a couple of minutes either side of the expected runtime.
Example:
(tvrip) set duration 28-32
See also automap