谷歌云-speech api返回空结果

POST https://speech.googleapis.com/v1/speech:recognize?key=YOUR_API_KEY
Content-Type: application/json

{
  "config": {
    "encoding": "LINEAR16",
    "sampleRateHertz": 16000,
    "languageCode": "en-US"
  },
  "audio": {
    "uri": "gs://your-bucket/your-audio-file.wav"
  }
}

{
  "error": {
    "code": 400,
    "message": "Invalid audio channel count"
  }
}

from google.cloud import speech_v1p1beta1 as speech
from google.cloud.speech_v1p1beta1 import enums

client = speech.SpeechClient()

audio = speech.RecognitionAudio(uri="gs://your-bucket/your-audio-file.wav")
config = speech.RecognitionConfig(
    encoding=enums.RecognitionConfig.AudioEncoding.LINEAR16,
    sample_rate_hertz=16000,
    language_code="en-US",
)

response = client.recognize(config=config, audio=audio)

for result in response.results:
    print("Transcript: {}".format(result.alternatives[0].transcript))