You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
48 lines
1.8 KiB
48 lines
1.8 KiB
"""Contain the speech perturbation augmentation model."""
|
|
from __future__ import absolute_import
|
|
from __future__ import division
|
|
from __future__ import print_function
|
|
|
|
from data_utils.augmentor.base import AugmentorBase
|
|
|
|
|
|
class SpeedPerturbAugmentor(AugmentorBase):
|
|
"""Augmentation model for adding speed perturbation.
|
|
|
|
See reference paper here:
|
|
http://www.danielpovey.com/files/2015_interspeech_augmentation.pdf
|
|
|
|
:param rng: Random generator object.
|
|
:type rng: random.Random
|
|
:param min_speed_rate: Lower bound of new speed rate to sample and should
|
|
not be smaller than 0.9.
|
|
:type min_speed_rate: float
|
|
:param max_speed_rate: Upper bound of new speed rate to sample and should
|
|
not be larger than 1.1.
|
|
:type max_speed_rate: float
|
|
"""
|
|
|
|
def __init__(self, rng, min_speed_rate, max_speed_rate):
|
|
if min_speed_rate < 0.9:
|
|
raise ValueError(
|
|
"Sampling speed below 0.9 can cause unnatural effects")
|
|
if max_speed_rate > 1.1:
|
|
raise ValueError(
|
|
"Sampling speed above 1.1 can cause unnatural effects")
|
|
self._min_speed_rate = min_speed_rate
|
|
self._max_speed_rate = max_speed_rate
|
|
self._rng = rng
|
|
|
|
def transform_audio(self, audio_segment):
|
|
"""Sample a new speed rate from the given range and
|
|
changes the speed of the given audio clip.
|
|
|
|
Note that this is an in-place transformation.
|
|
|
|
:param audio_segment: Audio segment to add effects to.
|
|
:type audio_segment: AudioSegment|SpeechSegment
|
|
"""
|
|
sampled_speed = self._rng.uniform(self._min_speed_rate,
|
|
self._max_speed_rate)
|
|
audio_segment.change_speed(sampled_speed)
|