A method and system for extracting segments from a broadcast television
signal uses a mean display attribute value of pixels of each successive
frame of a video component of the signal to identify segment transitions.
Elapsed times between the identified segment transitions are compared
with expected durations of segments, in order to detect intervals that
are likely to constitute segments. Groups of the detected intervals are
subjected to tests to see if they are temporally arranged in an expected
distribution typical of segments in broadcast signals. The mean display
attribute values concurrent with each detected segment are then used to
form a statistical profile for the segment. These statistical profiles
may be used to identify re-broadcast segments. Further a stream of mean
audio amplitudes is preferably used to supply further segment
transitions, to improve segment detection, and to provide more
statistical values.