mycroft-precise/precise/common.py

270 lines
8.5 KiB
Python

# Python 3
# Copyright (c) 2017 Mycroft AI Inc.
import json
from argparse import ArgumentParser
from os.path import isfile
from typing import *
import numpy as np
from precise.params import ListenerParams
pr = ListenerParams(window_t=0.1, hop_t=0.05, buffer_t=1.5,
sample_rate=16000, sample_depth=2,
n_mfcc=13, n_filt=20, n_fft=512)
lstm_units = 20
inhibit_t = 0.4
inhibit_dist_t = 1.0
inhibit_hop_t = 0.1
def create_parser(usage: str) -> ArgumentParser:
"""
Creates an argument parser from a condensed usage string in the format of:
:pos_arg_name int
This is the help message
which can span multiple lines
:-o --optional_arg str default_value
The type can be any valid python type
:-eo --extra-option
This adds args.extra_option as a bool
which is False by default
"""
first_line = [i for i in usage.split('\n') if i][0]
indent = ' ' * (len(first_line) - len(first_line.lstrip(' ')))
usage = usage.replace('\n' + indent, '\n')
defaults = {}
description, *descriptors = usage.split('\n:')
parser = ArgumentParser(description=description.strip())
for descriptor in descriptors:
try:
options, *help = descriptor.split('\n')
help = ' '.join(help).replace(' ', '')
if options.count(' ') == 1:
if options[0] == '-':
short, long = options.split(' ')
var_name = long.strip('-').replace('-', '_')
parser.add_argument(short, long, dest=var_name, action='store_true', help=help)
defaults[var_name] = False
else:
short, typ = options.split(' ')
parser.add_argument(short, type=eval(typ), help=help)
else:
short, long, typ, default = options.split(' ')
help += '. Default: ' + default
default = '' if default == '-' else default
parser.add_argument(short, long, type=eval(typ), default=default, help=help)
except Exception as e:
print(e.__class__.__name__ + ': ' + str(e))
print('While parsing:')
print(descriptor)
exit(1)
return parser
def buffer_to_audio(buffer: bytes) -> np.ndarray:
"""Convert a raw mono audio byte string to numpy array of floats"""
return np.fromstring(buffer, dtype='<i2').astype(np.float32, order='C') / 32768.0
def inject_params(model_name: str) -> ListenerParams:
params_file = model_name + '.params'
try:
global pr
with open(params_file) as f:
pr = ListenerParams(**json.load(f))
except (OSError, ValueError, TypeError):
print('Warning: Failed to load parameters from ' + params_file)
return pr
def save_params(model_name: str):
with open(model_name + '.params', 'w') as f:
json.dump(pr._asdict(), f)
def vectorize_raw(audio: np.ndarray) -> np.ndarray:
"""Turns audio into feature vectors, without clipping for length"""
from speechpy.feature import mfcc
return mfcc(audio, pr.sample_rate, pr.window_t, pr.hop_t, pr.n_mfcc, pr.n_filt, pr.n_fft)
def vectorize(audio: np.ndarray) -> np.ndarray:
"""
Args:
audio: Audio verified to be of `sample_rate`
Returns:
array<float>: Vector representation of audio
"""
if len(audio) > pr.max_samples:
audio = audio[-pr.max_samples:]
features = vectorize_raw(audio)
if len(features) < pr.n_features:
features = np.concatenate(
[np.zeros((pr.n_features - len(features), len(features[0]))), features])
if len(features) > pr.n_features:
features = features[-pr.n_features:]
return features
def vectorize_inhibit(audio: np.ndarray) -> np.ndarray:
"""
Returns an array of inputs generated from the
keyword audio that shouldn't cause an activation
"""
def samp(x):
return int(pr.sample_rate * x)
inputs = []
for offset in range(samp(inhibit_t), samp(inhibit_dist_t), samp(inhibit_hop_t)):
if len(audio) - offset < samp(pr.buffer_t / 2.):
break
inputs.append(vectorize(audio[:-offset]))
return np.array(inputs) if inputs else np.empty((0, pr.n_features, pr.feature_size))
def load_vector(name: str, vectorizer: Callable = vectorize) -> np.ndarray:
"""Loads and caches a vector input from a wav or npy file"""
import os
save_name = name if name.endswith('.npy') else os.path.join('cache', str(abs(hash(pr))),
vectorizer.__name__ + '.' + name + '.npy')
if os.path.isfile(save_name):
return np.load(save_name)
print('Loading ' + name + '...')
os.makedirs(os.path.dirname(save_name), exist_ok=True)
vec = vectorizer(load_audio(name))
np.save(save_name, vec)
return vec
def load_audio(file: Any) -> np.ndarray:
"""
Args:
file: Audio filename or file object
Returns:
samples: Sample rate and audio samples from 0..1
"""
import wavio
wav = wavio.read(file)
if wav.data.dtype != np.int16:
raise ValueError('Unsupported data type: ' + str(wav.data.dtype))
if wav.rate != pr.sample_rate:
raise ValueError('Unsupported sample rate: ' + str(wav.rate))
data = np.squeeze(wav.data)
return data.astype(np.float32) / float(np.iinfo(data.dtype).max)
def save_audio(filename: str, audio: np.ndarray):
import wavio
save_audio = (audio * np.iinfo(np.int16).max).astype(np.int16)
wavio.write(filename, save_audio, pr.sample_rate, sampwidth=pr.sample_depth, scale='none')
def glob_all(folder: str, filt: str) -> List[str]:
"""Recursive glob"""
import os
import fnmatch
matches = []
for root, dirnames, filenames in os.walk(folder):
for filename in fnmatch.filter(filenames, filt):
matches.append(os.path.join(root, filename))
return matches
def find_wavs(folder: str) -> Tuple[List[str], List[str]]:
"""Finds keyword and not-keyword wavs in folder"""
return glob_all(folder + '/keyword', '*.wav'), glob_all(folder + '/not-keyword', '*.wav')
def weighted_log_loss(yt, yp) -> Any:
"""
Binary crossentropy with a bias towards false negatives
yt: Target
yp: Prediction
"""
from keras import backend as K
weight = 0.9 # [0..1] where 1 is inf bias
pos_loss = -(0 + yt) * K.log(0 + yp + K.epsilon())
neg_loss = -(1 - yt) * K.log(1 - yp + K.epsilon())
return weight * K.sum(neg_loss) + (1. - weight) * K.sum(pos_loss)
def weighted_mse_loss(yt, yp) -> Any:
from keras import backend as K
weight = 0.9 # [0..1] where 1 is inf bias
total = K.sum(K.ones_like(yt))
neg_loss = total * K.sum(K.square(yp * (1 - yt))) / K.sum(1 - yt)
pos_loss = total * K.sum(K.square(1. - (yp * yt))) / K.sum(yt)
return weight * neg_loss + (1. - weight) * pos_loss
def false_pos(yt, yp) -> Any:
from keras import backend as K
return K.sum(K.cast(yp * (1 - yt) > 0.5, 'float')) / K.sum(1 - yt)
def false_neg(yt, yp) -> Any:
from keras import backend as K
return K.sum(K.cast((1 - yp) * (0 + yt) > 0.5, 'float')) / K.sum(0 + yt)
def load_keras() -> Any:
import keras
keras.losses.weighted_log_loss = weighted_log_loss
keras.metrics.false_pos = false_pos
keras.metrics.false_neg = false_neg
return keras
def load_precise_model(model_name: str) -> Any:
"""Loads a Keras model from file, handling custom loss function"""
if not model_name.endswith('.net'):
print('Warning: Unknown model type, ', model_name)
inject_params(model_name)
return load_keras().models.load_model(model_name)
def create_model(model_name: str, skip_acc: bool = False) -> Any:
"""
Load or create a precise model
Args:
model_name: Name of model
skip_acc: Whether to skip accuracy calculation while training
Returns:
model: Loaded Keras model
"""
if isfile(model_name):
print('Loading from ' + model_name + '...')
model = load_precise_model(model_name)
else:
from keras.layers.core import Dense
from keras.layers.recurrent import GRU
from keras.models import Sequential
model = Sequential()
model.add(GRU(lstm_units, activation='linear', input_shape=(pr.n_features, pr.feature_size),
dropout=0.3, name='net'))
model.add(Dense(1, activation='sigmoid'))
load_keras()
metrics = ['accuracy', false_pos, false_neg]
model.compile('rmsprop', weighted_log_loss, metrics=(not skip_acc) * metrics)
return model