实时语音识别
这段Python代码使用Google Cloud Speech-to-Text API和PyAudio库实现实时语音识别。它从麦克风捕获音频,将其流式传输到Speech-to-Text API,并打印转录文本。MicrophoneStream
类处理音频输入,main
函数设置语音识别客户端并处理音频流。
import os
import argparse
import io
import sys
import time
from google.cloud import speech
import pyaudio
from six.moves import queue
# 音频录制参数
RATE = 16000
CHUNK = int(RATE / 10) # 100ms
class MicrophoneStream(object):
"""打开一个录音流,作为生成器产生音频块。"""
def __init__(self, rate, chunk):
self._rate = rate
self._chunk = chunk
# 使用PyAudio创建一个音频接口
self._audio_interface = pyaudio.PyAudio()
self._audio_stream = self._audio_interface.open(
format=pyaudio.paInt16,
# API目前仅支持单声道音频
# https://goo.gl/z726ff
channels=1, rate=self._rate,
input=True, frames_per_buffer=self._chunk,
# 异步运行音频流以填充缓冲区对象。
# 这是必要的,以便在调用线程进行网络请求等操作时,输入设备的缓冲区不会溢出。
stream_callback=self._fill_buffer,
)
self.closed = False
self._buff = queue.Queue()
def _fill_buffer(self, in_data, frame_count, time_info, status_flags):
"""持续从音频流收集数据到缓冲区。"""
self._buff.put(in_data)
return None, pyaudio.paContinue
def generator(self, record_seconds):
start_time = time.time()
while not self.closed and time.time() - start_time < record_seconds:
# 使用阻塞的get()确保至少有一块数据,如果块为None则停止迭代,表示音频流结束。
chunk = self._buff.get()
if chunk is None:
return
data = [chunk]
# 现在使用任何其他缓冲数据。
while True:
try:
chunk = self._buff.get(block=False)
if chunk is None:
return
data.append(chunk)
except queue.Empty:
break
yield b''.join(data)
def close(self):
self.closed = True
# 向生成器发出终止信号,以便客户端的流式识别方法不会阻塞进程终止。
self._buff.put(None)
self._audio_stream.close()
self._audio_interface.terminate()
def __enter__(self):
return self
def __exit__(self, type, value, traceback):
self.close()
def main(record_seconds=10, language_code='en-US'):
# 请参阅 http://g.co/cloud/speech/docs/languages
# 获取支持的语言列表。
# language_code = 'en-US' # BCP-47语言标签
client = speech.SpeechClient()
config = speech.RecognitionConfig(
encoding=speech.RecognitionConfig.AudioEncoding.LINEAR16,
sample_rate_hertz=RATE,
language_code=language_code,
model="latest_long",
)
streaming_config = speech.StreamingRecognitionConfig(
config=config,
interim_results=True)
with MicrophoneStream(RATE, CHUNK) as stream:
audio_generator = stream.generator(record_seconds)
requests = (speech.StreamingRecognizeRequest(audio_content=content)
for content in audio_generator)
responses = client.streaming_recognize(streaming_config, requests)
# 现在,使用转录响应。
transcript = ""
for response in responses:
print(response)
# 转录完成后,打印结果。
for result in response.results:
if result.is_final:
alternative = result.alternatives[0]
transcript += alternative.transcript + " "
print(u'Transcript: {}'.format(transcript))
if __name__ == '__main__':
parser = argparse.ArgumentParser(description="可调节持续时间的实时语音识别。")
parser.add_argument('--duration', type=int, default=10, help="录音时长(秒)。")
parser.add_argument('--language_code', type=str, default='en-US', help="转录的语言代码。")
args = parser.parse_args()
print("请开始说话...")
main(record_seconds=args.duration, language_code=args.language_code)