Systems and methods for providing enhanced navigation of stored digital
video content based upon a content-based index. Includes generation and
storage of an index, as well as navigation based on the segments defined
by the index. An example system is embodied in a digital video recorder
that generates an index for locating commercial groups interleaved with
program content in a video presentation recorded from a television
broadcast. The commercial groups may be viewed without the intervening
program content or otherwise navigated based upon information in the
index and one or navigation functions. Example user interfaces and
several navigation functions are also provided.