gujarati-tisv / utils /.ipynb_checkpoints /VAD_segments-checkpoint.py
Irsh Vijayvargia
Add application file
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#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Tue Dec 18 16:22:41 2018
@author: Harry
Modified from https://github.com/wiseman/py-webrtcvad/blob/master/example.py
"""
import collections
import contextlib
import numpy as np
import sys
import librosa
import wave
import webrtcvad
from utils.hparam import hparam as hp
def read_wave(path, sr):
"""Reads a .wav file.
Takes the path, and returns (PCM audio data, sample rate).
Assumes sample width == 2
"""
with contextlib.closing(wave.open(path, 'rb')) as wf:
num_channels = wf.getnchannels()
assert num_channels == 1
sample_width = wf.getsampwidth()
assert sample_width == 2
sample_rate = wf.getframerate()
assert sample_rate in (8000, 16000, 32000, 48000)
pcm_data = wf.readframes(wf.getnframes())
data, _ = librosa.load(path, sr=sr)
assert len(data.shape) == 1
assert sr in (8000, 16000, 32000, 48000)
return data, pcm_data
class Frame(object):
"""Represents a "frame" of audio data."""
def __init__(self, bytes, timestamp, duration):
self.bytes = bytes
self.timestamp = timestamp
self.duration = duration
def frame_generator(frame_duration_ms, audio, sample_rate):
"""Generates audio frames from PCM audio data.
Takes the desired frame duration in milliseconds, the PCM data, and
the sample rate.
Yields Frames of the requested duration.
"""
n = int(sample_rate * (frame_duration_ms / 1000.0) * 2)
offset = 0
timestamp = 0.0
duration = (float(n) / sample_rate) / 2.0
while offset + n < len(audio):
yield Frame(audio[offset:offset + n], timestamp, duration)
timestamp += duration
offset += n
def vad_collector(sample_rate, frame_duration_ms,
padding_duration_ms, vad, frames):
"""Filters out non-voiced audio frames.
Given a webrtcvad.Vad and a source of audio frames, yields only
the voiced audio.
Uses a padded, sliding window algorithm over the audio frames.
When more than 90% of the frames in the window are voiced (as
reported by the VAD), the collector triggers and begins yielding
audio frames. Then the collector waits until 90% of the frames in
the window are unvoiced to detrigger.
The window is padded at the front and back to provide a small
amount of silence or the beginnings/endings of speech around the
voiced frames.
Arguments:
sample_rate - The audio sample rate, in Hz.
frame_duration_ms - The frame duration in milliseconds.
padding_duration_ms - The amount to pad the window, in milliseconds.
vad - An instance of webrtcvad.Vad.
frames - a source of audio frames (sequence or generator).
Returns: A generator that yields PCM audio data.
"""
num_padding_frames = int(padding_duration_ms / frame_duration_ms)
# We use a deque for our sliding window/ring buffer.
ring_buffer = collections.deque(maxlen=num_padding_frames)
# We have two states: TRIGGERED and NOTTRIGGERED. We start in the
# NOTTRIGGERED state.
triggered = False
voiced_frames = []
for frame in frames:
is_speech = vad.is_speech(frame.bytes, sample_rate)
if not triggered:
ring_buffer.append((frame, is_speech))
num_voiced = len([f for f, speech in ring_buffer if speech])
# If we're NOTTRIGGERED and more than 90% of the frames in
# the ring buffer are voiced frames, then enter the
# TRIGGERED state.
if num_voiced > 0.9 * ring_buffer.maxlen:
triggered = True
start = ring_buffer[0][0].timestamp
# We want to yield all the audio we see from now until
# we are NOTTRIGGERED, but we have to start with the
# audio that's already in the ring buffer.
for f, s in ring_buffer:
voiced_frames.append(f)
ring_buffer.clear()
else:
# We're in the TRIGGERED state, so collect the audio data
# and add it to the ring buffer.
voiced_frames.append(frame)
ring_buffer.append((frame, is_speech))
num_unvoiced = len([f for f, speech in ring_buffer if not speech])
# If more than 90% of the frames in the ring buffer are
# unvoiced, then enter NOTTRIGGERED and yield whatever
# audio we've collected.
if num_unvoiced > 0.9 * ring_buffer.maxlen:
triggered = False
yield (start, frame.timestamp + frame.duration)
ring_buffer.clear()
voiced_frames = []
# If we have any leftover voiced audio when we run out of input,
# yield it.
if voiced_frames:
yield (start, frame.timestamp + frame.duration)
def VAD_chunk(aggressiveness, path):
audio, byte_audio = read_wave(path, sr=hp.data.sr)
vad = webrtcvad.Vad(int(aggressiveness))
frames = frame_generator(20, byte_audio, hp.data.sr)
frames = list(frames)
times = vad_collector(hp.data.sr, 20, 200, vad, frames)
speech_times = []
speech_segs = []
for i, time in enumerate(times):
start = np.round(time[0],decimals=2)
end = np.round(time[1],decimals=2)
j = start
while j + .4 < end:
end_j = np.round(j+.4,decimals=2)
speech_times.append((j, end_j))
speech_segs.append(audio[int(j*hp.data.sr):int(end_j*hp.data.sr)])
j = end_j
else:
speech_times.append((j, end))
speech_segs.append(audio[int(j*hp.data.sr):int(end*hp.data.sr)])
return speech_times, speech_segs
if __name__ == '__main__':
speech_times, speech_segs = VAD_chunk(sys.argv[1], sys.argv[2])