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PaddleSpeech/audio/paddleaudio/utils/numeric.py

108 lines
3.6 KiB

# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from typing import Union
import numpy as np
__all__ = ["pcm16to32", "depth_convert"]
def pcm16to32(audio: np.ndarray) -> np.ndarray:
"""pcm int16 to float32
Args:
audio (np.ndarray): Waveform with dtype of int16.
Returns:
np.ndarray: Waveform with dtype of float32.
"""
if audio.dtype == np.int16:
audio = audio.astype("float32")
bits = np.iinfo(np.int16).bits
audio = audio / (2**(bits - 1))
return audio
def _safe_cast(y: np.ndarray, dtype: Union[type, str]) -> np.ndarray:
"""Data type casting in a safe way, i.e., prevent overflow or underflow.
Args:
y (np.ndarray): Input waveform array in 1D or 2D.
dtype (Union[type, str]): Data type of waveform.
Returns:
np.ndarray: `y` after safe casting.
"""
if 'float' in str(y.dtype):
return np.clip(y, np.finfo(dtype).min,
np.finfo(dtype).max).astype(dtype)
else:
return np.clip(y, np.iinfo(dtype).min,
np.iinfo(dtype).max).astype(dtype)
def depth_convert(y: np.ndarray, dtype: Union[type, str]) -> np.ndarray:
"""Convert audio array to target dtype safely.
This function convert audio waveform to a target dtype, with addition steps of
preventing overflow/underflow and preserving audio range.
Args:
y (np.ndarray): Input waveform array in 1D or 2D.
dtype (Union[type, str]): Data type of waveform.
Returns:
np.ndarray: `y` after safe casting.
"""
SUPPORT_DTYPE = ['int16', 'int8', 'float32', 'float64']
if y.dtype not in SUPPORT_DTYPE:
raise ParameterError(
'Unsupported audio dtype, '
f'y.dtype is {y.dtype}, supported dtypes are {SUPPORT_DTYPE}')
if dtype not in SUPPORT_DTYPE:
raise ParameterError(
'Unsupported audio dtype, '
f'target dtype is {dtype}, supported dtypes are {SUPPORT_DTYPE}')
if dtype == y.dtype:
return y
if dtype == 'float64' and y.dtype == 'float32':
return _safe_cast(y, dtype)
if dtype == 'float32' and y.dtype == 'float64':
return _safe_cast(y, dtype)
if dtype == 'int16' or dtype == 'int8':
if y.dtype in ['float64', 'float32']:
factor = np.iinfo(dtype).max
y = np.clip(y * factor, np.iinfo(dtype).min,
np.iinfo(dtype).max).astype(dtype)
y = y.astype(dtype)
else:
if dtype == 'int16' and y.dtype == 'int8':
factor = np.iinfo('int16').max / np.iinfo('int8').max - EPS
y = y.astype('float32') * factor
y = y.astype('int16')
else: # dtype == 'int8' and y.dtype=='int16':
y = y.astype('int32') * np.iinfo('int8').max / \
np.iinfo('int16').max
y = y.astype('int8')
if dtype in ['float32', 'float64']:
org_dtype = y.dtype
y = y.astype(dtype) / np.iinfo(org_dtype).max
return y