istft#
- ShortTimeFFT.istft(S, k0=0, k1=None, *, f_axis=-2, t_axis=-1)[source]#
- Inverse short-time Fourier transform. - It returns an array of dimension - S.ndim - 1which is real if- onesided_fftis set, else complex. If the STFT is not- invertible, or the parameters are out of bounds a- ValueErroris raised.- Parameters:
- S
- A complex valued array where f_axis denotes the frequency values and the t-axis dimension the temporal values of the STFT values. 
- k0, k1
- The start and the end index of the reconstructed signal. The default ( - k0 = 0,- k1 = None) assumes that the maximum length signal should be reconstructed.
- f_axis, t_axis
- The axes in S denoting the frequency and the time dimension. 
 
 - See also - invertible
- Check if STFT is invertible. 
- stft
- Perform Short-time Fourier transform. 
- scipy.signal.ShortTimeFFT
- Class this method belongs to. 
 - Notes - It is required that S has - f_ptsentries along the f_axis. For the t_axis it is assumed that the first entry corresponds to- p_min*- delta_t(being <= 0). The length of t_axis needs to be compatible with k1. I.e.,- S.shape[t_axis] >= self.p_max(k1)must hold, if k1 is not- None. Else k1 is set to- k_maxwith:- q_max = S.shape[t_range] + self.p_min k_max = (q_max - 1) * self.hop + self.m_num - self.m_num_mid - The Short-Time Fourier Transform section of the SciPy User Guide discussed the slicing behavior by means of an example.