torchaudio.functional.sliding_window_cmn(specgram: Tensor, cmn_window: int = 600, min_cmn_window: int = 100, center: bool = False, norm_vars: bool = False) Tensor[source]

Apply sliding-window cepstral mean (and optionally variance) normalization per utterance.

This feature supports the following devices: CPU, CUDA This API supports the following properties: TorchScript
  • specgram (Tensor) – Tensor of spectrogram of dimension (…, time, freq)

  • cmn_window (int, optional) – Window in frames for running average CMN computation (int, default = 600)

  • min_cmn_window (int, optional) – Minimum CMN window used at start of decoding (adds latency only at start). Only applicable if center == false, ignored if center==true (int, default = 100)

  • center (bool, optional) – If true, use a window centered on the current frame (to the extent possible, modulo end effects). If false, window is to the left. (bool, default = false)

  • norm_vars (bool, optional) – If true, normalize variance to one. (bool, default = false)


Tensor matching input shape (…, freq, time)

Return type:



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