spectral_flatness

function of dascore.transform.spectral_descriptors source

spectral_flatness(
    patch: Patch ,
    dim: str | None[str, None] = None,
    fmin: float | None[float, None] = None,
    fmax: float | None[float, None] = None,
    spectral_format: Literal[‘auto’, ‘fft’, ‘amplitude’, ‘power’, ‘density’] = auto,
    negative_frequencies: Literal[‘auto’, ‘drop’, ‘raise’, ‘keep’] = auto,
)-> ‘PatchType’

Compute spectral flatness from a Fourier-domain patch.

Spectral flatness is the ratio between the geometric mean and arithmetic mean of the power spectrum.

Values near 1 indicate white-noise-like spectra. Values near 0 indicate tonal or peaked spectra. The input patch must already be transformed with Patch.dft or Patch.stft.

Parameters

Parameter Description
patch Fourier-domain DASCore patch from dft or stft.
dim Frequency dimension over which to compute the descriptor. This can be
either the original dimension name, such as "time", or the Fourier
dimension name, such as "ft_time". If omitted, a single Fourier
dimension is inferred.
fmin Optional lower frequency bound.
fmax Optional upper frequency bound.
spectral_format Representation of the spectral data. "auto" uses DASCore DFT/STFT
metadata when available. Other options are "fft" for complex Fourier
coefficients, "amplitude" for amplitude spectra, "power" for
power spectra, and "density" for power spectral densities.
negative_frequencies How to handle negative frequency bins. "auto" drops negative bins
only when power is symmetric, "drop" always uses non-negative
frequencies, "raise" rejects spectra with negative bins, and
"keep" includes them in the calculation.

Returns

PatchType Patch containing spectral flatness.