torchaudio.prototype.functional.extend_pitch

torchaudio.prototype.functional.extend_pitch(base: Tensor, pattern: Union[int, List[float], Tensor])

Extend the given time series values with multipliers of them.

Given a series of fundamental frequencies (pitch), this function appends its harmonic overtones or inharmonic partials.

Parameters:

• base (torch.Tensor) – Base time series, like fundamental frequencies (Hz). Shape: (…, time, 1).

• pattern (int, list of python:floats or torch.Tensor) –

  If int, the number of pitch series after the operation. pattern - 1 tones are added, so that the resulting Tensor contains up to pattern-th overtones of the given series.

  If list of float or torch.Tensor, it must be one dimensional, representing the custom multiplier of the fundamental frequency.

Returns:

Oscillator frequencies (Hz). Shape: (…, time, num_tones).

Return type:

Tensor

Example

>>> # fundamental frequency
>>> f0 = torch.linspace(1, 5, 5).unsqueeze(-1)
>>> f0
tensor([[1.],
        [2.],
        [3.],
        [4.],
        [5.]])
>>> # Add harmonic overtones, up to 3rd.
>>> f = extend_pitch(f0, 3)
>>> f.shape
torch.Size([5, 3])
>>> f
tensor([[ 1.,  2.,  3.],
        [ 2.,  4.,  6.],
        [ 3.,  6.,  9.],
        [ 4.,  8., 12.],
        [ 5., 10., 15.]])
>>> # Add custom (inharmonic) partials.
>>> f = extend_pitch(f0, torch.tensor([1, 2.1, 3.3, 4.5]))
>>> f.shape
torch.Size([5, 4])
>>> f
tensor([[ 1.0000,  2.1000,  3.3000,  4.5000],
        [ 2.0000,  4.2000,  6.6000,  9.0000],
        [ 3.0000,  6.3000,  9.9000, 13.5000],
        [ 4.0000,  8.4000, 13.2000, 18.0000],
        [ 5.0000, 10.5000, 16.5000, 22.5000]])

Tutorials using extend_pitch:

Additive Synthesis

Additive Synthesis