Konno Ohmachi smoothing

Konno-Ohmachi smoothing is a smoothing algorithm proposed by Konno & Ohmachi (1998), which achieves a "uniform-span" smoothing to noisy curves presented in logarithmic scale. The figure below shows the comparison of Konno-Ohmachi smoothing versus linear-span smoothing (e.g., sine window averaging). Compared to uniform-span smoother, Konno-Ohmachi does not over-smooth low frequency contents.

Two MATLAB functions (".p" files) are written, which implement this smoothing algorithm.
  • fastKonnoOhmachi(): It smooths a frequency spectrum rather fast. See below for usage. [link]
  • fasterKonnoOhmachi(): Exact same input and output. Faster speed enabled by using multiple cores of your CPU. [link]

% USAGE: y = fastKonnoOhmachi(input_signal,freq_array)
%        y = fastKonnoOhmachi(input_signal,freq_array,smooth_parameter)
% [Inputs]
%     input_signal: Signal to be smoothed in frequency domain. (1 column)
%     freq_array: Frequency array corresponding to the signal. It must also
%                 be a column vector and have the same length as the input
%                 signal.
%     smooth_parameter: A parameter determining the degree of smoothing,
%                       the lower this parameter is, the more the signal
%                       is smoothed. Only integral values between 10 and 50
%                       are allowed. (Default: 40)
% [Output]
%     y: Smoothed signal (1 column only)

Jian S,
Apr 24, 2015, 12:00 AM
Jian S,
Apr 24, 2015, 12:00 AM