SUMMARYThe problem of finding the point in time at which a known audio or video source (reference signal) appears in a long audio or video source (input signal) is referred to as a time series search, in contrast to a text string search. In a time series search, a search can be performed quickly by combining the audio and video, and then identifying several search conditions using logical equations. Thus, in this paper the authors describe the application of the time series active search method, a method to search audio signals proposed in the authors' previous paper, to video searches. Next, the authors propose an efficient algorithm for AND searches and OR searches of reference signals. In addition, the authors propose a multimodal AND search which combines audio and video. The proposed algorithms are faster than combining the results of searches performed individually. For instance, in an OR search of a reference signal, when the mutual similarity in the reference signals is above 0.8, five reference signals can be searched in a search time that is 1.2 times faster than searching one reference signal.