1. A method of retrieving media data, the method comprising: determining that a manifest file for media content indicates that the media content includes a first period and a second period, that the manifest file indicates that the first and second periods are continuous, and that advertisement media data is available for insertion between the first and second periods; selecting a first adaptation set in the first period based at least in part on characteristics signaled for the first adaptation set; retrieving media data of the first adaptation set based on the selection of the first adaptation set; and retrieving media data of a second adaptation set in the second period that is associated with the first adaptation set based on the selection of the first adaptation set.