Files
WhisperLiveKit/whisperlivekit/remove_silences.py

110 lines
4.6 KiB
Python

from whisperlivekit.timed_objects import ASRToken
import re
MIN_SILENCE_DURATION = 4 #in seconds
END_SILENCE_DURATION = 8 #in seconds. you should keep it important to not have false positive when the model lag is important
END_SILENCE_DURATION_VAC = 3 #VAC is good at detecting silences, but we want to skip the smallest silences
def blank_to_silence(tokens):
full_string = ''.join([t.text for t in tokens])
patterns = [re.compile(r'(?:\s*\[BLANK_AUDIO\]\s*)+'), re.compile(r'(?:\s*\[typing\]\s*)+')]
matches = []
for pattern in patterns:
for m in pattern.finditer(full_string):
matches.append({
'start': m.start(),
'end': m.end()
})
if matches:
# cleaned = pattern.sub(' ', full_string).strip()
# print("Cleaned:", cleaned)
cumulated_len = 0
silence_token = None
cleaned_tokens = []
for token in tokens:
if matches:
start = cumulated_len
end = cumulated_len + len(token.text)
cumulated_len = end
if start >= matches[0]['start'] and end <= matches[0]['end']:
if silence_token: #previous token was already silence
silence_token.start = min(silence_token.start, token.start)
silence_token.end = max(silence_token.end, token.end)
else: #new silence
silence_token = ASRToken(
start=token.start,
end=token.end,
speaker=-2,
probability=0.95
)
else:
if silence_token: #there was silence but no more
if silence_token.end - silence_token.start >= MIN_SILENCE_DURATION:
cleaned_tokens.append(
silence_token
)
silence_token = None
matches.pop(0)
cleaned_tokens.append(token)
# print(cleaned_tokens)
return cleaned_tokens
return tokens
def no_token_to_silence(tokens):
new_tokens = []
silence_token = None
for token in tokens:
if token.speaker == -2:
if new_tokens and new_tokens[-1].speaker == -2: #if token is silence and previous one too
new_tokens[-1].end = token.end
else:
new_tokens.append(token)
last_end = new_tokens[-1].end if new_tokens else 0.0
if token.start - last_end >= MIN_SILENCE_DURATION: #if token is not silence but important gap
if new_tokens and new_tokens[-1].speaker == -2:
new_tokens[-1].end = token.start
else:
silence_token = ASRToken(
start=last_end,
end=token.start,
speaker=-2,
probability=0.95
)
new_tokens.append(silence_token)
if token.speaker != -2:
new_tokens.append(token)
return new_tokens
def ends_with_silence(tokens, buffer_transcription, buffer_diarization, current_time, vac_detected_silence):
if not tokens:
return [], buffer_transcription, buffer_diarization
last_token = tokens[-1]
if tokens and (
current_time - last_token.end >= END_SILENCE_DURATION
or
(current_time - last_token.end >= 3 and vac_detected_silence)
):
if last_token.speaker == -2:
last_token.end = current_time
else:
tokens.append(
ASRToken(
start=tokens[-1].end,
end=current_time,
speaker=-2,
probability=0.95
)
)
buffer_transcription = "" # for whisperstreaming backend, we should probably validate the buffer has because of the silence
buffer_diarization = ""
return tokens, buffer_transcription, buffer_diarization
def handle_silences(tokens, buffer_transcription, buffer_diarization, current_time, vac_detected_silence):
tokens = blank_to_silence(tokens) #useful for simulstreaming backend which tends to generate [BLANK_AUDIO] text
tokens = no_token_to_silence(tokens)
tokens, buffer_transcription, buffer_diarization = ends_with_silence(tokens, buffer_transcription, buffer_diarization, current_time, vac_detected_silence)
return tokens, buffer_transcription, buffer_diarization