Lukin-Todd

The Lukin-Todd (LT) is a combination method that employs an energy-smearing function as a local information measure. Each entry X_{k, m} is computed as a weighted average of the samples X_{k, m}[p], where larger weights are given to samples on low-smearing neighborhoods. The LT method is computationally costly when compared to most other methods, as computing the smearing function requires sorting the samples in each neighborhood.

Note

It’s highly recommended to use NumPy version 2.0 or higher for this combination method, as the performance of the sorting procedure is improved substantially.

Further reading

  • Package release article: To be added.

  • D.Sc. thesis on combination methods: M. do V. M. da Costa, Novel time-frequency representations for music information retrieval, D.Sc., Federal University of Rio de Janeiro, Rio de Janeiro, Brasil (2020 Apr.).

  • LT reference paper: A. Lukin and J. G. Todd, “Adaptive time-frequency resolution for analysis and processing of audio,” in 120th Audio Engineering Society Convention. Paris, France: Audio Engineering Society, May 2006.

Calling signature

ctfr.methods.lt(signal, sr, *, <shared parameters>, lk, lm, eta)
ctfr.methods.lt_from_specs(specs, *, <shared parameters>, lk, lm, eta)

Note

As with all combination methods, you can also use ctfr.ctfr() or ctfr.ctfr_from_specs().

See ctfr.ctfr() and ctfr.ctfr_from_specs() for more details on the shared parameters for computing CTFRs with this package. The parameters specific to this method (passed as keyword arguments) are described below.

Parameters

lk (int > 0, odd, optional)

Width in frequency bins of the analysis window used in the local energy smearing computation. Defaults to 21.

lm (int > 0, odd, optional)

Width in time frames of the analysis window used in the local energy smearing computation. Defaults to 11.

eta (float >= 0, optional)

Factor used in the computation of combination weights. Defaults to 8.