a method and related interface system for facilitating manual detection of advertising sections within a video signal . the method includes sampling frames from every n 1 frames to be reference frames in the video signal , and showing the reference frames to a user . if the user finds that a given reference frame is an advertising frame , setting n 2 to be smaller than n 1 , sampling frames from every n 2 frames between the given reference frame and its adjacent reference frame to be second layer reference frames , showing the second layer reference frames to the user such that the user can further detail selection of advertising frames , and locating advertising frames more precisely .