mirror of
https://github.com/morpheus65535/bazarr
synced 2024-12-22 07:42:32 +00:00
882 lines
31 KiB
Python
882 lines
31 KiB
Python
"""
|
|
Class summary
|
|
=============
|
|
|
|
.. autosummary::
|
|
|
|
DataSource
|
|
StringDataSource
|
|
ADSFactory
|
|
ADSFactory.AudioDataSource
|
|
ADSFactory.ADSDecorator
|
|
ADSFactory.OverlapADS
|
|
ADSFactory.LimiterADS
|
|
ADSFactory.RecorderADS
|
|
DataValidator
|
|
AudioEnergyValidator
|
|
|
|
"""
|
|
|
|
|
|
from abc import ABCMeta, abstractmethod
|
|
import math
|
|
from array import array
|
|
from .io import Rewindable, from_file, BufferAudioSource, PyAudioSource
|
|
from .exceptions import DuplicateArgument
|
|
import sys
|
|
|
|
|
|
try:
|
|
import numpy
|
|
_WITH_NUMPY = True
|
|
except ImportError as e:
|
|
_WITH_NUMPY = False
|
|
|
|
try:
|
|
from builtins import str
|
|
basestring = str
|
|
except ImportError as e:
|
|
if sys.version_info >= (3, 0):
|
|
basestring = str
|
|
|
|
|
|
|
|
__all__ = ["DataSource", "DataValidator", "StringDataSource", "ADSFactory", "AudioEnergyValidator"]
|
|
|
|
|
|
class DataSource():
|
|
"""
|
|
Base class for objects passed to :func:`auditok.core.StreamTokenizer.tokenize`.
|
|
Subclasses should implement a :func:`DataSource.read` method.
|
|
"""
|
|
__metaclass__ = ABCMeta
|
|
|
|
@abstractmethod
|
|
def read(self):
|
|
"""
|
|
Read a piece of data read from this source.
|
|
If no more data is available, return None.
|
|
"""
|
|
|
|
|
|
class DataValidator():
|
|
"""
|
|
Base class for a validator object used by :class:`.core.StreamTokenizer` to check
|
|
if read data is valid.
|
|
Subclasses should implement :func:`is_valid` method.
|
|
"""
|
|
__metaclass__ = ABCMeta
|
|
|
|
@abstractmethod
|
|
def is_valid(self, data):
|
|
"""
|
|
Check whether `data` is valid
|
|
"""
|
|
|
|
class StringDataSource(DataSource):
|
|
"""
|
|
A class that represent a :class:`DataSource` as a string buffer.
|
|
Each call to :func:`DataSource.read` returns on character and moves one step forward.
|
|
If the end of the buffer is reached, :func:`read` returns None.
|
|
|
|
:Parameters:
|
|
|
|
`data` :
|
|
a basestring object.
|
|
|
|
"""
|
|
|
|
def __init__(self, data):
|
|
|
|
self._data = None
|
|
self._current = 0
|
|
self.set_data(data)
|
|
|
|
|
|
def read(self):
|
|
"""
|
|
Read one character from buffer.
|
|
|
|
:Returns:
|
|
|
|
Current character or None if end of buffer is reached
|
|
"""
|
|
|
|
if self._current >= len(self._data):
|
|
return None
|
|
self._current += 1
|
|
return self._data[self._current - 1]
|
|
|
|
def set_data(self, data):
|
|
"""
|
|
Set a new data buffer.
|
|
|
|
:Parameters:
|
|
|
|
`data` : a basestring object
|
|
New data buffer.
|
|
"""
|
|
|
|
if not isinstance(data, basestring):
|
|
raise ValueError("data must an instance of basestring")
|
|
self._data = data
|
|
self._current = 0
|
|
|
|
|
|
|
|
class ADSFactory:
|
|
"""
|
|
Factory class that makes it easy to create an :class:`ADSFactory.AudioDataSource` object that implements
|
|
:class:`DataSource` and can therefore be passed to :func:`auditok.core.StreamTokenizer.tokenize`.
|
|
|
|
Whether you read audio data from a file, the microphone or a memory buffer, this factory
|
|
instantiates and returns the right :class:`ADSFactory.AudioDataSource` object.
|
|
|
|
There are many other features you want your :class:`ADSFactory.AudioDataSource` object to have, such as:
|
|
memorize all read audio data so that you can rewind and reuse it (especially useful when
|
|
reading data from the microphone), read a fixed amount of data (also useful when reading
|
|
from the microphone), read overlapping audio frames (often needed when dosing a spectral
|
|
analysis of data).
|
|
|
|
:func:`ADSFactory.ads` automatically creates and return object with the desired behavior according
|
|
to the supplied keyword arguments.
|
|
|
|
"""
|
|
|
|
@staticmethod
|
|
def _check_normalize_args(kwargs):
|
|
|
|
for k in kwargs:
|
|
if not k in ["block_dur", "hop_dur", "block_size", "hop_size", "max_time", "record",
|
|
"audio_source", "filename", "data_buffer", "frames_per_buffer", "sampling_rate",
|
|
"sample_width", "channels", "sr", "sw", "ch", "asrc", "fn", "fpb", "db", "mt",
|
|
"rec", "bd", "hd", "bs", "hs"]:
|
|
raise ValueError("Invalid argument: {0}".format(k))
|
|
|
|
if "block_dur" in kwargs and "bd" in kwargs:
|
|
raise DuplicateArgument("Either 'block_dur' or 'bd' must be specified, not both")
|
|
|
|
if "hop_dur" in kwargs and "hd" in kwargs:
|
|
raise DuplicateArgument("Either 'hop_dur' or 'hd' must be specified, not both")
|
|
|
|
if "block_size" in kwargs and "bs" in kwargs:
|
|
raise DuplicateArgument("Either 'block_size' or 'bs' must be specified, not both")
|
|
|
|
if "hop_size" in kwargs and "hs" in kwargs:
|
|
raise DuplicateArgument("Either 'hop_size' or 'hs' must be specified, not both")
|
|
|
|
if "max_time" in kwargs and "mt" in kwargs:
|
|
raise DuplicateArgument("Either 'max_time' or 'mt' must be specified, not both")
|
|
|
|
if "audio_source" in kwargs and "asrc" in kwargs:
|
|
raise DuplicateArgument("Either 'audio_source' or 'asrc' must be specified, not both")
|
|
|
|
if "filename" in kwargs and "fn" in kwargs:
|
|
raise DuplicateArgument("Either 'filename' or 'fn' must be specified, not both")
|
|
|
|
if "data_buffer" in kwargs and "db" in kwargs:
|
|
raise DuplicateArgument("Either 'filename' or 'db' must be specified, not both")
|
|
|
|
if "frames_per_buffer" in kwargs and "fbb" in kwargs:
|
|
raise DuplicateArgument("Either 'frames_per_buffer' or 'fpb' must be specified, not both")
|
|
|
|
if "sampling_rate" in kwargs and "sr" in kwargs:
|
|
raise DuplicateArgument("Either 'sampling_rate' or 'sr' must be specified, not both")
|
|
|
|
if "sample_width" in kwargs and "sw" in kwargs:
|
|
raise DuplicateArgument("Either 'sample_width' or 'sw' must be specified, not both")
|
|
|
|
if "channels" in kwargs and "ch" in kwargs:
|
|
raise DuplicateArgument("Either 'channels' or 'ch' must be specified, not both")
|
|
|
|
if "record" in kwargs and "rec" in kwargs:
|
|
raise DuplicateArgument("Either 'record' or 'rec' must be specified, not both")
|
|
|
|
|
|
kwargs["bd"] = kwargs.pop("block_dur", None) or kwargs.pop("bd", None)
|
|
kwargs["hd"] = kwargs.pop("hop_dur", None) or kwargs.pop("hd", None)
|
|
kwargs["bs"] = kwargs.pop("block_size", None) or kwargs.pop("bs", None)
|
|
kwargs["hs"] = kwargs.pop("hop_size", None) or kwargs.pop("hs", None)
|
|
kwargs["mt"] = kwargs.pop("max_time", None) or kwargs.pop("mt", None)
|
|
kwargs["asrc"] = kwargs.pop("audio_source", None) or kwargs.pop("asrc", None)
|
|
kwargs["fn"] = kwargs.pop("filename", None) or kwargs.pop("fn", None)
|
|
kwargs["db"] = kwargs.pop("data_buffer", None) or kwargs.pop("db", None)
|
|
|
|
record = kwargs.pop("record", False)
|
|
if not record:
|
|
record = kwargs.pop("rec", False)
|
|
if not isinstance(record, bool):
|
|
raise TypeError("'record' must be a boolean")
|
|
|
|
kwargs["rec"] = record
|
|
|
|
# keep long names for arguments meant for BufferAudioSource and PyAudioSource
|
|
if "frames_per_buffer" in kwargs or "fpb" in kwargs:
|
|
kwargs["frames_per_buffer"] = kwargs.pop("frames_per_buffer", None) or kwargs.pop("fpb", None)
|
|
|
|
if "sampling_rate" in kwargs or "sr" in kwargs:
|
|
kwargs["sampling_rate"] = kwargs.pop("sampling_rate", None) or kwargs.pop("sr", None)
|
|
|
|
if "sample_width" in kwargs or "sw" in kwargs:
|
|
kwargs["sample_width"] = kwargs.pop("sample_width", None) or kwargs.pop("sw", None)
|
|
|
|
if "channels" in kwargs or "ch" in kwargs:
|
|
kwargs["channels"] = kwargs.pop("channels", None) or kwargs.pop("ch", None)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
@staticmethod
|
|
def ads(**kwargs):
|
|
|
|
"""
|
|
Create an return an :class:`ADSFactory.AudioDataSource`. The type and behavior of the object is the result
|
|
of the supplied parameters.
|
|
|
|
:Parameters:
|
|
|
|
*No parameters* :
|
|
read audio data from the available built-in microphone with the default parameters.
|
|
The returned :class:`ADSFactory.AudioDataSource` encapsulate an :class:`io.PyAudioSource` object and hence
|
|
it accepts the next four parameters are passed to use instead of their default values.
|
|
|
|
`sampling_rate`, `sr` : *(int)*
|
|
number of samples per second. Default = 16000.
|
|
|
|
`sample_width`, `sw` : *(int)*
|
|
number of bytes per sample (must be in (1, 2, 4)). Default = 2
|
|
|
|
`channels`, `ch` : *(int)*
|
|
number of audio channels. Default = 1 (only this value is currently accepted)
|
|
|
|
`frames_per_buffer`, `fpb` : *(int)*
|
|
number of samples of PyAudio buffer. Default = 1024.
|
|
|
|
`audio_source`, `asrc` : an `AudioSource` object
|
|
read data from this audio source
|
|
|
|
`filename`, `fn` : *(string)*
|
|
build an `io.AudioSource` object using this file (currently only wave format is supported)
|
|
|
|
`data_buffer`, `db` : *(string)*
|
|
build an `io.BufferAudioSource` using data in `data_buffer`. If this keyword is used,
|
|
`sampling_rate`, `sample_width` and `channels` are passed to `io.BufferAudioSource`
|
|
constructor and used instead of default values.
|
|
|
|
`max_time`, `mt` : *(float)*
|
|
maximum time (in seconds) to read. Default behavior: read until there is no more data
|
|
available.
|
|
|
|
`record`, `rec` : *(bool)*
|
|
save all read data in cache. Provide a navigable object which boasts a `rewind` method.
|
|
Default = False.
|
|
|
|
`block_dur`, `bd` : *(float)*
|
|
processing block duration in seconds. This represents the quantity of audio data to return
|
|
each time the :func:`read` method is invoked. If `block_dur` is 0.025 (i.e. 25 ms) and the sampling
|
|
rate is 8000 and the sample width is 2 bytes, :func:`read` returns a buffer of 0.025 * 8000 * 2 = 400
|
|
bytes at most. This parameter will be looked for (and used if available) before `block_size`.
|
|
If neither parameter is given, `block_dur` will be set to 0.01 second (i.e. 10 ms)
|
|
|
|
|
|
`hop_dur`, `hd` : *(float)*
|
|
quantity of data to skip from current processing window. if `hop_dur` is supplied then there
|
|
will be an overlap of `block_dur` - `hop_dur` between two adjacent blocks. This
|
|
parameter will be looked for (and used if available) before `hop_size`. If neither parameter
|
|
is given, `hop_dur` will be set to `block_dur` which means that there will be no overlap
|
|
between two consecutively read blocks.
|
|
|
|
`block_size`, `bs` : *(int)*
|
|
number of samples to read each time the `read` method is called. Default: a block size
|
|
that represents a window of 10ms, so for a sampling rate of 16000, the default `block_size`
|
|
is 160 samples, for a rate of 44100, `block_size` = 441 samples, etc.
|
|
|
|
`hop_size`, `hs` : *(int)*
|
|
determines the number of overlapping samples between two adjacent read windows. For a
|
|
`hop_size` of value *N*, the overlap is `block_size` - *N*. Default : `hop_size` = `block_size`,
|
|
means that there is no overlap.
|
|
|
|
:Returns:
|
|
|
|
An AudioDataSource object that has the desired features.
|
|
|
|
:Exampels:
|
|
|
|
1. **Create an AudioDataSource that reads data from the microphone (requires Pyaudio) with default audio parameters:**
|
|
|
|
.. code:: python
|
|
|
|
from auditok import ADSFactory
|
|
ads = ADSFactory.ads()
|
|
ads.get_sampling_rate()
|
|
16000
|
|
ads.get_sample_width()
|
|
2
|
|
ads.get_channels()
|
|
1
|
|
|
|
|
|
2. **Create an AudioDataSource that reads data from the microphone with a sampling rate of 48KHz:**
|
|
|
|
.. code:: python
|
|
|
|
from auditok import ADSFactory
|
|
ads = ADSFactory.ads(sr=48000)
|
|
ads.get_sampling_rate()
|
|
48000
|
|
|
|
3. **Create an AudioDataSource that reads data from a wave file:**
|
|
|
|
.. code:: python
|
|
|
|
import auditok
|
|
from auditok import ADSFactory
|
|
ads = ADSFactory.ads(fn=auditok.dataset.was_der_mensch_saet_mono_44100_lead_trail_silence)
|
|
ads.get_sampling_rate()
|
|
44100
|
|
ads.get_sample_width()
|
|
2
|
|
ads.get_channels()
|
|
1
|
|
|
|
4. **Define size of read blocks as 20 ms**
|
|
|
|
.. code:: python
|
|
|
|
import auditok
|
|
from auditok import ADSFactory
|
|
'''
|
|
we know samling rate for previous file is 44100 samples/second
|
|
so 10 ms are equivalent to 441 samples and 20 ms to 882
|
|
'''
|
|
block_size = 882
|
|
ads = ADSFactory.ads(bs = 882, fn=auditok.dataset.was_der_mensch_saet_mono_44100_lead_trail_silence)
|
|
ads.open()
|
|
# read one block
|
|
data = ads.read()
|
|
ads.close()
|
|
len(data)
|
|
1764
|
|
assert len(data) == ads.get_sample_width() * block_size
|
|
|
|
5. **Define block size as a duration (use block_dur or bd):**
|
|
|
|
.. code:: python
|
|
|
|
import auditok
|
|
from auditok import ADSFactory
|
|
dur = 0.25 # second
|
|
ads = ADSFactory.ads(bd = dur, fn=auditok.dataset.was_der_mensch_saet_mono_44100_lead_trail_silence)
|
|
'''
|
|
we know samling rate for previous file is 44100 samples/second
|
|
for a block duration of 250 ms, block size should be 0.25 * 44100 = 11025
|
|
'''
|
|
ads.get_block_size()
|
|
11025
|
|
assert ads.get_block_size() == int(0.25 * 44100)
|
|
ads.open()
|
|
# read one block
|
|
data = ads.read()
|
|
ads.close()
|
|
len(data)
|
|
22050
|
|
assert len(data) == ads.get_sample_width() * ads.get_block_size()
|
|
|
|
6. **Read overlapping blocks (one of hope_size, hs, hop_dur or hd > 0):**
|
|
|
|
For better readability we'd better use :class:`auditok.io.BufferAudioSource` with a string buffer:
|
|
|
|
.. code:: python
|
|
|
|
import auditok
|
|
from auditok import ADSFactory
|
|
'''
|
|
we supply a data beffer instead of a file (keyword 'bata_buffer' or 'db')
|
|
sr : sampling rate = 16 samples/sec
|
|
sw : sample width = 1 byte
|
|
ch : channels = 1
|
|
'''
|
|
buffer = "abcdefghijklmnop" # 16 bytes = 1 second of data
|
|
bd = 0.250 # block duration = 250 ms = 4 bytes
|
|
hd = 0.125 # hop duration = 125 ms = 2 bytes
|
|
ads = ADSFactory.ads(db = "abcdefghijklmnop", bd = bd, hd = hd, sr = 16, sw = 1, ch = 1)
|
|
ads.open()
|
|
ads.read()
|
|
'abcd'
|
|
ads.read()
|
|
'cdef'
|
|
ads.read()
|
|
'efgh'
|
|
ads.read()
|
|
'ghij'
|
|
data = ads.read()
|
|
assert data == 'ijkl'
|
|
|
|
7. **Limit amount of read data (use max_time or mt):**
|
|
|
|
.. code:: python
|
|
|
|
'''
|
|
We know audio file is larger than 2.25 seconds
|
|
We want to read up to 2.25 seconds of audio data
|
|
'''
|
|
ads = ADSFactory.ads(mt = 2.25, fn=auditok.dataset.was_der_mensch_saet_mono_44100_lead_trail_silence)
|
|
ads.open()
|
|
data = []
|
|
while True:
|
|
d = ads.read()
|
|
if d is None:
|
|
break
|
|
data.append(d)
|
|
|
|
ads.close()
|
|
data = b''.join(data)
|
|
assert len(data) == int(ads.get_sampling_rate() * 2.25 * ads.get_sample_width() * ads.get_channels())
|
|
"""
|
|
|
|
# copy user's dicionary (shallow copy)
|
|
kwargs = kwargs.copy()
|
|
|
|
# check and normalize keyword arguments
|
|
ADSFactory._check_normalize_args(kwargs)
|
|
|
|
block_dur = kwargs.pop("bd")
|
|
hop_dur = kwargs.pop("hd")
|
|
block_size = kwargs.pop("bs")
|
|
hop_size = kwargs.pop("hs")
|
|
max_time = kwargs.pop("mt")
|
|
audio_source = kwargs.pop("asrc")
|
|
filename = kwargs.pop("fn")
|
|
data_buffer = kwargs.pop("db")
|
|
record = kwargs.pop("rec")
|
|
|
|
# Case 1: an audio source is supplied
|
|
if audio_source is not None:
|
|
if (filename, data_buffer) != (None, None):
|
|
raise Warning("You should provide one of 'audio_source', 'filename' or 'data_buffer'\
|
|
keyword parameters. 'audio_source' will be used")
|
|
|
|
# Case 2: a file name is supplied
|
|
elif filename is not None:
|
|
if data_buffer is not None:
|
|
raise Warning("You should provide one of 'filename' or 'data_buffer'\
|
|
keyword parameters. 'filename' will be used")
|
|
audio_source = from_file(filename)
|
|
|
|
# Case 3: a data_buffer is supplied
|
|
elif data_buffer is not None:
|
|
audio_source = BufferAudioSource(data_buffer = data_buffer, **kwargs)
|
|
|
|
# Case 4: try to access native audio input
|
|
else:
|
|
audio_source = PyAudioSource(**kwargs)
|
|
|
|
|
|
if block_dur is not None:
|
|
if block_size is not None:
|
|
raise DuplicateArgument("Either 'block_dur' or 'block_size' can be specified, not both")
|
|
else:
|
|
block_size = int(audio_source.get_sampling_rate() * block_dur)
|
|
elif block_size is None:
|
|
# Set default block_size to 10 ms
|
|
block_size = int(audio_source.get_sampling_rate() / 100)
|
|
|
|
# Instantiate base AudioDataSource
|
|
ads = ADSFactory.AudioDataSource(audio_source=audio_source, block_size=block_size)
|
|
|
|
# Limit data to be read
|
|
if max_time is not None:
|
|
ads = ADSFactory.LimiterADS(ads=ads, max_time=max_time)
|
|
|
|
# Record, rewind and reuse data
|
|
if record:
|
|
ads = ADSFactory.RecorderADS(ads=ads)
|
|
|
|
# Read overlapping blocks of data
|
|
if hop_dur is not None:
|
|
if hop_size is not None:
|
|
raise DuplicateArgument("Either 'hop_dur' or 'hop_size' can be specified, not both")
|
|
else:
|
|
hop_size = int(audio_source.get_sampling_rate() * hop_dur)
|
|
|
|
if hop_size is not None:
|
|
if hop_size <= 0 or hop_size > block_size:
|
|
raise ValueError("hop_size must be > 0 and <= block_size")
|
|
if hop_size < block_size:
|
|
ads = ADSFactory.OverlapADS(ads=ads, hop_size=hop_size)
|
|
|
|
return ads
|
|
|
|
|
|
class AudioDataSource(DataSource):
|
|
"""
|
|
Base class for AudioDataSource objects.
|
|
It inherits from DataSource and encapsulates an AudioSource object.
|
|
"""
|
|
|
|
def __init__(self, audio_source, block_size):
|
|
|
|
self.audio_source = audio_source
|
|
self.block_size = block_size
|
|
|
|
def get_block_size(self):
|
|
return self.block_size
|
|
|
|
def set_block_size(self, size):
|
|
self.block_size = size
|
|
|
|
def get_audio_source(self):
|
|
return self.audio_source
|
|
|
|
def set_audio_source(self, audio_source):
|
|
self.audio_source = audio_source
|
|
|
|
def open(self):
|
|
self.audio_source.open()
|
|
|
|
def close(self):
|
|
self.audio_source.close()
|
|
|
|
def is_open(self):
|
|
return self.audio_source.is_open()
|
|
|
|
def get_sampling_rate(self):
|
|
return self.audio_source.get_sampling_rate()
|
|
|
|
def get_sample_width(self):
|
|
return self.audio_source.get_sample_width()
|
|
|
|
def get_channels(self):
|
|
return self.audio_source.get_channels()
|
|
|
|
|
|
def rewind(self):
|
|
if isinstance(self.audio_source, Rewindable):
|
|
self.audio_source.rewind()
|
|
else:
|
|
raise Exception("Audio source is not rewindable")
|
|
|
|
|
|
|
|
def is_rewindable(self):
|
|
return isinstance(self.audio_source, Rewindable)
|
|
|
|
|
|
def read(self):
|
|
return self.audio_source.read(self.block_size)
|
|
|
|
|
|
class ADSDecorator(AudioDataSource):
|
|
"""
|
|
Base decorator class for AudioDataSource objects.
|
|
"""
|
|
__metaclass__ = ABCMeta
|
|
|
|
def __init__(self, ads):
|
|
self.ads = ads
|
|
|
|
self.get_block_size = self.ads.get_block_size
|
|
self.set_block_size = self.ads.set_block_size
|
|
self.get_audio_source = self.ads.get_audio_source
|
|
self.open = self.ads.open
|
|
self.close = self.ads.close
|
|
self.is_open = self.ads.is_open
|
|
self.get_sampling_rate = self.ads.get_sampling_rate
|
|
self.get_sample_width = self.ads.get_sample_width
|
|
self.get_channels = self.ads.get_channels
|
|
|
|
def is_rewindable(self):
|
|
return self.ads.is_rewindable
|
|
|
|
def rewind(self):
|
|
self.ads.rewind()
|
|
self._reinit()
|
|
|
|
def set_audio_source(self, audio_source):
|
|
self.ads.set_audio_source(audio_source)
|
|
self._reinit()
|
|
|
|
def open(self):
|
|
if not self.ads.is_open():
|
|
self.ads.open()
|
|
self._reinit()
|
|
|
|
@abstractmethod
|
|
def _reinit(self):
|
|
pass
|
|
|
|
|
|
class OverlapADS(ADSDecorator):
|
|
"""
|
|
A class for AudioDataSource objects that can read and return overlapping audio frames
|
|
"""
|
|
|
|
def __init__(self, ads, hop_size):
|
|
ADSFactory.ADSDecorator.__init__(self, ads)
|
|
|
|
if hop_size <= 0 or hop_size > self.get_block_size():
|
|
raise ValueError("hop_size must be either 'None' or \
|
|
between 1 and block_size (both inclusive)")
|
|
self.hop_size = hop_size
|
|
self._actual_block_size = self.get_block_size()
|
|
self._reinit()
|
|
|
|
|
|
def _get_block_size():
|
|
return self._actual_block_size
|
|
|
|
|
|
def _read_first_block(self):
|
|
# For the first call, we need an entire block of size 'block_size'
|
|
block = self.ads.read()
|
|
if block is None:
|
|
return None
|
|
|
|
# Keep a slice of data in cache and append it in the next call
|
|
if len(block) > self._hop_size_bytes:
|
|
self._cache = block[self._hop_size_bytes:]
|
|
|
|
# Up from the next call, we will use '_read_next_blocks'
|
|
# and we only read 'hop_size'
|
|
self.ads.set_block_size(self.hop_size)
|
|
self.read = self._read_next_blocks
|
|
|
|
return block
|
|
|
|
def _read_next_blocks(self):
|
|
block = self.ads.read()
|
|
if block is None:
|
|
return None
|
|
|
|
# Append block to cache data to ensure overlap
|
|
block = self._cache + block
|
|
# Keep a slice of data in cache only if we have a full length block
|
|
# if we don't that means that this is the last block
|
|
if len(block) == self._block_size_bytes:
|
|
self._cache = block[self._hop_size_bytes:]
|
|
else:
|
|
self._cache = None
|
|
|
|
return block
|
|
|
|
def read(self):
|
|
pass
|
|
|
|
def _reinit(self):
|
|
self._cache = None
|
|
self.ads.set_block_size(self._actual_block_size)
|
|
self._hop_size_bytes = self.hop_size * \
|
|
self.get_sample_width() * \
|
|
self.get_channels()
|
|
self._block_size_bytes = self.get_block_size() * \
|
|
self.get_sample_width() * \
|
|
self.get_channels()
|
|
self.read = self._read_first_block
|
|
|
|
|
|
|
|
class LimiterADS(ADSDecorator):
|
|
"""
|
|
A class for AudioDataSource objects that can read a fixed amount of data.
|
|
This can be useful when reading data from the microphone or from large audio files.
|
|
"""
|
|
|
|
def __init__(self, ads, max_time):
|
|
ADSFactory.ADSDecorator.__init__(self, ads)
|
|
|
|
self.max_time = max_time
|
|
self._reinit()
|
|
|
|
def read(self):
|
|
if self._total_read_bytes >= self._max_read_bytes:
|
|
return None
|
|
block = self.ads.read()
|
|
if block is None:
|
|
return None
|
|
self._total_read_bytes += len(block)
|
|
|
|
if self._total_read_bytes >= self._max_read_bytes:
|
|
self.close()
|
|
|
|
return block
|
|
|
|
|
|
def _reinit(self):
|
|
self._max_read_bytes = int(self.max_time * self.get_sampling_rate()) * \
|
|
self.get_sample_width() * \
|
|
self.get_channels()
|
|
self._total_read_bytes = 0
|
|
|
|
|
|
|
|
class RecorderADS(ADSDecorator):
|
|
"""
|
|
A class for AudioDataSource objects that can record all audio data they read,
|
|
with a rewind facility.
|
|
"""
|
|
|
|
def __init__(self, ads):
|
|
ADSFactory.ADSDecorator.__init__(self, ads)
|
|
|
|
self._reinit()
|
|
|
|
def read(self):
|
|
pass
|
|
|
|
def _read_and_rec(self):
|
|
# Read and save read data
|
|
block = self.ads.read()
|
|
if block is not None:
|
|
self._cache.append(block)
|
|
|
|
return block
|
|
|
|
|
|
def _read_simple(self):
|
|
# Read without recording
|
|
return self.ads.read()
|
|
|
|
def rewind(self):
|
|
if self._record:
|
|
# If has been recording, create a new BufferAudioSource
|
|
# from recorded data
|
|
dbuffer = self._concatenate(self._cache)
|
|
asource = BufferAudioSource(dbuffer, self.get_sampling_rate(),
|
|
self.get_sample_width(),
|
|
self.get_channels())
|
|
|
|
|
|
self.set_audio_source(asource)
|
|
self.open()
|
|
self._cache = []
|
|
self._record = False
|
|
self.read = self._read_simple
|
|
|
|
else:
|
|
self.ads.rewind()
|
|
if not self.is_open():
|
|
self.open()
|
|
|
|
|
|
def is_rewindable(self):
|
|
return True
|
|
|
|
def _reinit(self):
|
|
# when audio_source is replaced, start recording again
|
|
self._record = True
|
|
self._cache = []
|
|
self.read = self._read_and_rec
|
|
|
|
def _concatenate(self, data):
|
|
try:
|
|
# should always work for python 2
|
|
# work for python 3 ONLY if data is a list (or an iterator)
|
|
# whose each element is a 'bytes' objects
|
|
return b''.join(data)
|
|
except TypeError:
|
|
# work for 'str' in python 2 and python 3
|
|
return ''.join(data)
|
|
|
|
|
|
class AudioEnergyValidator(DataValidator):
|
|
"""
|
|
The most basic auditok audio frame validator.
|
|
This validator computes the log energy of an input audio frame
|
|
and return True if the result is >= a given threshold, False
|
|
otherwise.
|
|
|
|
:Parameters:
|
|
|
|
`sample_width` : *(int)*
|
|
Number of bytes of one audio sample. This is used to convert data from `basestring` or `Bytes` to
|
|
an array of floats.
|
|
|
|
`energy_threshold` : *(float)*
|
|
A threshold used to check whether an input data buffer is valid.
|
|
"""
|
|
|
|
|
|
if _WITH_NUMPY:
|
|
|
|
_formats = {1: numpy.int8 , 2: numpy.int16, 4: numpy.int32}
|
|
|
|
@staticmethod
|
|
def _convert(signal, sample_width):
|
|
return numpy.array(numpy.frombuffer(signal, dtype=AudioEnergyValidator._formats[sample_width]), dtype=numpy.float64)
|
|
|
|
@staticmethod
|
|
def _signal_energy(signal):
|
|
return float(numpy.dot(signal, signal)) / len(signal)
|
|
|
|
@staticmethod
|
|
def _signal_log_energy(signal):
|
|
energy = AudioEnergyValidator._signal_energy(signal)
|
|
if energy <= 0:
|
|
return -200
|
|
return 10. * numpy.log10(energy)
|
|
|
|
else:
|
|
|
|
|
|
_formats = {1: 'b' , 2: 'h', 4: 'i'}
|
|
|
|
@staticmethod
|
|
def _convert(signal, sample_width):
|
|
return array("d", array(AudioEnergyValidator._formats[sample_width], signal))
|
|
|
|
@staticmethod
|
|
def _signal_energy(signal):
|
|
energy = 0.
|
|
for a in signal:
|
|
energy += a * a
|
|
return energy / len(signal)
|
|
|
|
@staticmethod
|
|
def _signal_log_energy(signal):
|
|
energy = AudioEnergyValidator._signal_energy(signal)
|
|
if energy <= 0:
|
|
return -200
|
|
return 10. * math.log10(energy)
|
|
|
|
|
|
def __init__(self, sample_width, energy_threshold=45):
|
|
self.sample_width = sample_width
|
|
self._energy_threshold = energy_threshold
|
|
|
|
|
|
def is_valid(self, data):
|
|
"""
|
|
Check if data is valid. Audio data will be converted into an array (of
|
|
signed values) of which the log energy is computed. Log energy is computed
|
|
as follows:
|
|
|
|
.. code:: python
|
|
|
|
arr = AudioEnergyValidator._convert(signal, sample_width)
|
|
energy = float(numpy.dot(arr, arr)) / len(arr)
|
|
log_energy = 10. * numpy.log10(energy)
|
|
|
|
|
|
:Parameters:
|
|
|
|
`data` : either a *string* or a *Bytes* buffer
|
|
`data` is converted into a numerical array using the `sample_width`
|
|
given in the constructor.
|
|
|
|
:Retruns:
|
|
|
|
True if `log_energy` >= `energy_threshold`, False otherwise.
|
|
"""
|
|
|
|
signal = AudioEnergyValidator._convert(data, self.sample_width)
|
|
return AudioEnergyValidator._signal_log_energy(signal) >= self._energy_threshold
|
|
|
|
def get_energy_threshold(self):
|
|
return self._energy_threshold
|
|
|
|
def set_energy_threshold(self, threshold):
|
|
self._energy_threshold = threshold
|
|
|