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Shift

Added in v0.5.0

Shift the samples forwards or backwards, with or without rollover

Shift API

ℹ This only applies to version 0.33.0 and newer. If you are using an older version, you should consider upgrading. Or if you really want to keep using the old version, you can check the "Old Shift API (<=v0.32.0)" section below

min_shift: float | int
Default: -0.5. Minimum amount of shifting in time. See also shift_unit.
max_shift: float | int
Default: 0.5. Maximum amount of shifting in time. See also shift_unit.
shift_unit: str • choices: "fraction", "samples", "seconds"

Default: "fraction" Defines the unit of the value of min_shift and max_shift.

  • "fraction": Fraction of the total sound length
  • "samples": Number of audio samples
  • "seconds": Number of seconds
rollover: bool
Default: True. When set to True, samples that roll beyond the first or last position are re-introduced at the last or first. When set to False, samples that roll beyond the first or last position are discarded. In other words, rollover=False results in an empty space (with zeroes).
fade_duration: float • unit: seconds • range: 0.0 or [0.00025, ∞)
Default: 0.005. If you set this to a positive number, there will be a fade in and/or out at the "stitch" (that was the start or the end of the audio before the shift). This can smooth out an unwanted abrupt change between two consecutive samples (which sounds like a transient/click/pop). This parameter denotes the duration of the fade in seconds. To disable the fading feature, set this parameter to 0.0.
p: float • range: [0.0, 1.0]
Default: 0.5. The probability of applying this transform.

Old Shift API (<=v0.32.0)

⚠ This only applies to version 0.32.0 and older

min_fraction: float • range: [-1, 1]
Default: -0.5. Minimum fraction of total sound length to shift.
max_fraction: float • range: [-1, 1]
Default: 0.5. Maximum fraction of total sound length to shift.
rollover: bool
Default: True. When set to True, samples that roll beyond the last position are re-introduced at the first position, and samples that roll beyond the first position are re-introduced at the last position. When set to False, samples that roll beyond the first or last position are discarded. In other words, rollover=False results in an empty space (with zeroes).
fade: bool
Default: False. When set to True, there will be a short fade in and/or out at the "stitch" (that was the start or the end of the audio before the shift). This can smooth out an unwanted abrupt change between two consecutive samples, which would otherwise sound like a transient/click/pop.
fade_duration: float • unit: seconds
Default: 0.01. If fade=True, then this is the duration of the fade in seconds.
p: float • range: [0.0, 1.0]
Default: 0.5. The probability of applying this transform.

Source code

audiomentations/augmentations/shift.py