Skip to main content
`Ctrl`+`K`
scipy.signal.ShortTimeFFT.

# from_window

classmethod ShortTimeFFT.from_window(win_param, fs, nperseg, noverlap, *, symmetric_win=False, fft_mode='onesided', mfft=None, scale_to=None, phase_shift=0)

  Instantiate `ShortTimeFFT` by using `get_window`.

  The method `get_window` is used to create a window of length nperseg. The parameter names noverlap, and nperseg are used here, since they more inline with other classical STFT libraries.

  Parameters:
    win_param: Union[str, tuple, float],

      Parameters passed to `get_window`. For windows with no parameters, it may be a string (e.g., `'hann'`), for parametrized windows a tuple, (e.g., `('gaussian', 2.)`) or a single float specifying the shape parameter of a kaiser window (i.e. `4.` and `('kaiser', 4.)` are equal. See `get_window` for more details.

    fs float

      Sampling frequency of input signal. Its relation to the sampling interval `T` is `T = 1 / fs`.

    nperseg: int

      Window length in samples, which corresponds to the `m_num`.

    noverlap: int

      Window overlap in samples. It relates to the `hop` increment by `hop = npsereg - noverlap`.

    symmetric_win: bool

      If `True` then a symmetric window is generated, else a periodic window is generated (default). Though symmetric windows seem for most applications to be more sensible, the default of a periodic windows was chosen to correspond to the default of `get_window`.

    fft_mode‘twosided’, ‘centered’, ‘onesided’, ‘onesided2X’

      Mode of FFT to be used (default ‘onesided’). See property `fft_mode` for details.

    mfft: int | None

      Length of the FFT used, if a zero padded FFT is desired. If `None` (default), the length of the window `win` is used.

    scale_to‘magnitude’, ‘psd’ | None

      If not `None` (default) the window function is scaled, so each STFT column represents either a ‘magnitude’ or a power spectral density (‘psd’) spectrum. This parameter sets the property `scaling` to the same value. See method `scale_to` for details.

    phase_shift int | None

      If set, add a linear phase `phase_shift` / `mfft` * `f` to each frequency `f`. The default value 0 ensures that there is no phase shift on the zeroth slice (in which t=0 is centered). See property `phase_shift` for more details.

  See also

  `scipy.signal.get_window`

    Return a window of a given length and type.

  `from_dual`

    Create instance using dual window.

  `ShortTimeFFT`

    Create instance using standard initializer.

  Examples

  The following instances `SFT0` and `SFT1` are equivalent:

      >>> from scipy.signal import ShortTimeFFT, get_window
      >>> nperseg = 9  # window length
      >>> w = get_window(('gaussian', 2.), nperseg)
      >>> fs = 128  # sampling frequency
      >>> hop = 3  # increment of STFT time slice
      >>> SFT0 = ShortTimeFFT(w, hop, fs=fs)
      >>> SFT1 = ShortTimeFFT.from_window(('gaussian', 2.), fs, nperseg,
      ...                                 noverlap=nperseg-hop)