an image and pulse analysis system and method including a datasieve comprising a succession of ordinal filtering means receiving at least a selected part of a signal conglomerate and filtering the at least a selected part of the signal conglomerate to produce a bandpass filter output , the ordinal filtering means having window lengths increasing from n up to m , whereby an input signal to each successive filtering means is formed from the output of the previous filtering means ; selection means for selecting a predetermined subset of bandpass filter outputs from outputs of the succession of filtering means ; and arithmetic means for adding together the signals of the subset to produce an output signal containing only wanted signals determined by the selection means ; data storage means for storing data relating to a sought - for - feature or object which may exist in a field from which data is derived for presenting to the datasieve ; comparison means for matching or comparing the stored data with the output signal of the datasieve ; and selection means to select from the input signal only data having a high degree of match to the data in the data storage means .