谷歌语音 API GRPC 超时

Question

我正在编写一个使用 Google Cloud Platform 的流式语音识别 API 的应用程序。这个想法是主循环持续监控麦克风输入（总是在待机状态下监听），一旦音频峰值超过某个阈值水平，它就会产生一个 MicrophoneStream 类实例以发出语音识别请求。这是一种绕过 Google API 对流持续时间的一分钟限制的方法。 1 分钟后，系统要么返回待机状态监测声级，要么创建一个新的 MicrophoneStream 实例以防有人仍在讲话。

问题是一分钟后 MicrophoneStream 实例并没有安静地运行并引发异常：

grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with 
(StatusCode.INVALID_ARGUMENT, Client GRPC deadline too short. Should be at 
least: 3 * audio-duration + 5 seconds. Current deadline is: 
188.99906457681209 second(s). Required at least: 194 second(s).)> 

看起来像known bug in Google API，但是我在任何地方都没有找到解决方案。我一直在寻找几天试图弄清楚如何更改 GRPC 截止日期设置以防止此错误。或者，我很乐意直接忽略它，但是 try: 和 Except Exception: 似乎也不起作用。有任何想法吗？以下是 Google 的 Python 实现示例：

from __future__ import division

import re
import sys

from google.cloud import speech
from google.cloud.speech import enums
from google.cloud.speech import types
import pyaudio
from six.moves import queue

# Audio recording parameters
RATE = 16000
CHUNK = int(RATE / 10)  # 100ms


class MicrophoneStream(object):
    """Opens a recording stream as a generator yielding the audio chunks."""
    def __init__(self, rate, chunk):
        self._rate = rate
        self._chunk = chunk

        # Create a thread-safe buffer of audio data
        self._buff = queue.Queue()
        self.closed = True

    def __enter__(self):
        self._audio_interface = pyaudio.PyAudio()
        self._audio_stream = self._audio_interface.open(
            format=pyaudio.paInt16,
            channels=1, rate=self._rate,
            input=True, frames_per_buffer=self._chunk,
            stream_callback=self._fill_buffer,
        )

        self.closed = False

        return self

    def __exit__(self, type, value, traceback):
        self._audio_stream.stop_stream()
        self._audio_stream.close()
        self.closed = True
        self._buff.put(None)
        self._audio_interface.terminate()

    def _fill_buffer(self, in_data, frame_count, time_info, status_flags):
        """Continuously collect data from the audio stream, into the buffer."""
        self._buff.put(in_data)
        return None, pyaudio.paContinue

    def generator(self):
        while not self.closed:
            chunk = self._buff.get()
            if chunk is None:
                return
            data = [chunk]

            # Now consume whatever other data's still buffered.
            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)
# [END audio_stream]


def listen_print_loop(responses):
    num_chars_printed = 0
    for response in responses:
        if not response.results:
            continue

        result = response.results[0]
        if not result.alternatives:
            continue

        # Display the transcription of the top alternative.
        transcript = result.alternatives[0].transcript

        overwrite_chars = ' ' * (num_chars_printed - len(transcript))

        if not result.is_final:
            sys.stdout.write(transcript + overwrite_chars + '\r')
            sys.stdout.flush()

            num_chars_printed = len(transcript)

        else:
            print(transcript + overwrite_chars)

            if re.search(r'\b(exit|quit)\b', transcript, re.I):
                print('Exiting..')
                break

            num_chars_printed = 0


def main():
    language_code = 'en-US'  # a BCP-47 language tag

    client = speech.SpeechClient()
    config = types.RecognitionConfig(
        encoding=enums.RecognitionConfig.AudioEncoding.LINEAR16,
        sample_rate_hertz=RATE,
        language_code=language_code)
    streaming_config = types.StreamingRecognitionConfig(
        config=config,
        interim_results=True)

    with MicrophoneStream(RATE, CHUNK) as stream:
        audio_generator = stream.generator()
        requests = (types.StreamingRecognizeRequest(audio_content=content)
                    for content in audio_generator)

        responses = client.streaming_recognize(streaming_config, requests)

        # Now, put the transcription responses to use.
        listen_print_loop(responses)


if __name__ == '__main__':
    main()

Answer 1

迟到的答案，但我还是写了： Google 语音的硬超时设置为 60 秒。您不能通过 grpc 向其流式传输超过 60 秒。 例如，一种解决方法是每 55 秒重新启动一次 grpc 调用。