Coarse-graining is performed. Time-series values above its mean are given 1, and those below the mean are 0.
the input time series
Entropy of words in the binary alphabet of length 3.
B.D. Fulcher and N.S. Jones. hctsa: A computational framework for automated time-series phenotyping using massive feature extraction. Cell Systems 5, 527 (2017).
B.D. Fulcher, M.A. Little, N.S. Jones Highly comparative time-series analysis: the empirical structure of time series and their methods. J. Roy. Soc. Interface 10, 83 (2013).
motiftwo_entro3(WWWusage)#>  1.200579