Stockwell提出的S变换管饭用于各个领域的信号分析，起源于小波变换。在语音信号处理当中等到了较为广泛的运用。- Returns the Stockwell Transform of the timeseries. Reference is Localization of the Complex Spectrum: The S Transform IEEE Transactions on Signal Processing, vol. 44., number 4, April 1996