class SpeechToTextEngine:
""" Class to perform speech-to-text transcription and related functionality """
def __init__(self, scorer='deepspeech_model.scorer') -> None:
""" Initializing the DeepSpeech model """
self.model = Model(model_path=Path(__file__).parents[2].joinpath(
'deepspeech_model.pbmm').absolute().as_posix())
self.model.enableExternalScorer(scorer_path=Path(
__file__).parents[2].joinpath(scorer).absolute().as_posix())
def run(self, audio) -> str:
""" Receives the audio, normalizes it and is sent to the model to be transcribed. Returns the result of the
transcribe audio in string format."""
normalized_audio = normalize_audio_input(audio)
audio_streams = BytesIO(normalized_audio)
with wave.Wave_read(audio_streams) as wav:
audio_streams = np.frombuffer(wav.readframes(wav.getnframes()),
np.int16)
results = self.model.stt(audio_buffer=audio_streams)
return results
def run_with_metadata(self, audio) -> Metadata:
normalized_audio = normalize_audio_input(audio)
audio_streams = BytesIO(normalized_audio)
with wave.Wave_read(audio_streams) as wav:
audio_streams = np.frombuffer(wav.readframes(wav.getnframes()),
np.int16)
results = self.model.sttWithMetadata(audio_buffer=audio_streams)
return results
def add_hot_words(self, data) -> list:
""" Receives data in form of hot-words and boosts, adds them to the language model and return the list of the
added hot-words """
all_hot_words = []
try:
logger.info('----------------------------------------------------')
for hot_word in data:
# Change all the characters of the hot-word to lower case
word = hot_word.lower()
# Get numeric value of the boost
boost = float(data.get(hot_word))
# Adding the hot-word and its boost to the language model
self.model.addHotWord(hot_word, boost)
# Printing on the prompt the activity
logger.info(
f"`{word}` hot-word with boost `{boost}` was added.")
all_hot_words.append(word)
return all_hot_words
except RuntimeError:
return []
def erase_hot_word(self, hot_words) -> None:
try:
for hot_word in hot_words:
self.model.eraseHotWord(hot_word)
logger.info(f"`{hot_word}` hot-word is erased.")
logger.info('----------------------------------------------------')
except RuntimeError:
return
def clear_hot_words(self) -> str:
try:
self.model.clearHotWords()
return f"All hot-words were erased."
except RuntimeError:
return f"No more hot-words are left."
def sample_rate(self):
return self.model.sampleRate()
class SpeechToTextEngine:
""" Class to perform speech-to-text transcription and related functionality """
FORMAT = pyaudio.paInt16
SAMPLE_RATE = 16000
CHANNELS = 1
BLOCKS_PER_SECOND = 50
def __init__(self, scorer='deepspeech_model.scorer') -> None:
""" Initializing the DeepSpeech model """
self.model = Model(model_path=Path(__file__).parents[2].joinpath(
'deepspeech_model.pbmm').absolute().as_posix())
self.model.enableExternalScorer(scorer_path=Path(
__file__).parents[2].joinpath(scorer).absolute().as_posix())
self.vad = webrtcvad.Vad(mode=3)
self.sample_rate = self.SAMPLE_RATE
self.buffer_queue = queue.Queue()
def run(self, audio) -> str:
""" Receives the audio, normalizes it and is sent to the model to be transcribed. Returns the result of the
transcribe audio in string format."""
normalized_audio = normalize_audio_input(audio)
audio_streams = BytesIO(normalized_audio)
with wave.Wave_read(audio_streams) as wav:
audio_streams = np.frombuffer(wav.readframes(wav.getnframes()),
np.int16)
results = self.model.stt(audio_buffer=audio_streams)
return results
def run_with_metadata(self, audio) -> Metadata:
normalized_audio = normalize_audio_input(audio)
audio_streams = BytesIO(normalized_audio)
with wave.Wave_read(audio_streams) as wav:
audio_streams = np.frombuffer(wav.readframes(wav.getnframes()),
np.int16)
results = self.model.sttWithMetadata(audio_buffer=audio_streams)
return results
def add_hot_words(self, data) -> list:
""" Receives data in form of hot-words and boosts, adds them to the language model and return the list of the
added hot-words """
all_hot_words = []
try:
logger.info('----------------------------------------------------')
for hot_word in data:
# Change all the characters of the hot-word to lower case
word = hot_word.lower()
# Get numeric value of the boost
boost = float(data.get(hot_word))
# Adding the hot-word and its boost to the language model
self.model.addHotWord(hot_word, boost)
# Printing on the prompt the activity
logger.info(
f"`{word}` hot-word with boost `{boost}` was added.")
all_hot_words.append(word)
return all_hot_words
except RuntimeError:
return []
def erase_hot_word(self, hot_words) -> None:
try:
for hot_word in hot_words:
self.model.eraseHotWord(hot_word)
logger.info(f"`{hot_word}` hot-word is erased.")
logger.info('----------------------------------------------------')
except RuntimeError:
return
def clear_hot_words(self) -> str:
try:
self.model.clearHotWords()
return f"All hot-words were erased."
except RuntimeError:
return f"No more hot-words are left."
def deep_stream(self):
return self.model.createStream()
def frame_generator(self, audio, sample_rate=16000, frame_duration_ms=30):
"""
Takes the desired frame duration in milliseconds, the PCM data, and
the sample rate. Yields Frames of the requested duration.
"""
# audio = np.frombuffer(audio, np.int16)
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
