torchaudio.prototype.functional.chroma_filterbank(sample_rate: int, n_freqs: int, n_chroma: int, *, tuning: float = 0.0, ctroct: float = 5.0, octwidth: Optional[float] = 2.0, norm: int = 2, base_c: bool = True)[source]

Create a frequency-to-chroma conversion matrix. Implementation adapted from librosa.

  • sample_rate (int) – Sample rate.

  • n_freqs (int) – Number of input frequencies.

  • n_chroma (int) – Number of output chroma.

  • tuning (float, optional) – Tuning deviation from A440 in fractions of a chroma bin. (Default: 0.0)

  • ctroct (float, optional) – Center of Gaussian dominance window to weight filters by, in octaves. (Default: 5.0)

  • octwidth (float or None, optional) – Width of Gaussian dominance window to weight filters by, in octaves. If None, then disable weighting altogether. (Default: 2.0)

  • norm (int, optional) – order of norm to normalize filter bank by. (Default: 2)

  • base_c (bool, optional) – If True, then start filter bank at C. Otherwise, start at A. (Default: True)


Chroma filter bank, with shape (n_freqs, n_chroma).

Return type:



Access comprehensive developer documentation for PyTorch

View Docs


Get in-depth tutorials for beginners and advanced developers

View Tutorials


Find development resources and get your questions answered

View Resources