mindspore.dataset.audio.Fade

class mindspore.dataset.audio.Fade(fade_in_len=0, fade_out_len=0, fade_shape=FadeShape.LINEAR)

Add a fade in and/or fade out to an waveform.

Parameters

• fade_in_len (int, optional) – Length of fade-in (time frames), which must be non-negative. Default: 0.

• fade_out_len (int, optional) – Length of fade-out (time frames), which must be non-negative. Default: 0.

• fade_shape (FadeShape, optional) –

  Shape of fade, five different types can be chosen as defined in FadeShape. Default: FadeShape.LINEAR.

  • FadeShape.QUARTER_SINE, means it tend to 0 in an quarter sin function.

  • FadeShape.HALF_SINE, means it tend to 0 in an half sin function.

  • FadeShape.LINEAR, means it linear to 0.

  • FadeShape.LOGARITHMIC, means it tend to 0 in an logrithmic function.

  • FadeShape.EXPONENTIAL, means it tend to 0 in an exponential function.

Raises

• RuntimeError – If fade_in_len exceeds waveform length.

• RuntimeError – If fade_out_len exceeds waveform length.

Supported Platforms:

CPU

Examples

>>> import numpy as np
>>> import mindspore.dataset as ds
>>> import mindspore.dataset.audio as audio
>>>
>>> # Use the transform in dataset pipeline mode
>>> waveform = np.random.random([5, 16])  # 5 samples
>>> numpy_slices_dataset = ds.NumpySlicesDataset(data=waveform, column_names=["audio"])
>>> transforms = [audio.Fade(fade_in_len=3, fade_out_len=2, fade_shape=audio.FadeShape.LINEAR)]
>>> numpy_slices_dataset = numpy_slices_dataset.map(operations=transforms, input_columns=["audio"])
>>> for item in numpy_slices_dataset.create_dict_iterator(num_epochs=1, output_numpy=True):
...     print(item["audio"].shape, item["audio"].dtype)
...     break
(16,) float64
>>>
>>> # Use the transform in eager mode
>>> waveform = np.random.random([16])  # 1 sample
>>> output = audio.Fade(fade_in_len=3, fade_out_len=2, fade_shape=audio.FadeShape.LINEAR)(waveform)
>>> print(output.shape, output.dtype)
(16,) float64

Tutorial Examples:

• Illustration of audio transforms