Using the API

The Google Speech API enables developers to convert audio to text. The API recognizes over 80 languages and variants, to support your global user base.

Warning

This is a Beta release of Google Speech API. This API is not intended for real-time usage in critical applications.

Client

Client objects provide a means to configure your application. Each instance holds an authenticated connection to the Natural Language service.

For an overview of authentication in google-cloud-python, see Authentication.

Assuming your environment is set up as described in that document, create an instance of Client.

>>> from google.cloud import speech
>>> client = speech.Client()

Asychronous Recognition

The async_recognize() sends audio data to the Speech API and initiates a Long Running Operation. Using this operation, you can periodically poll for recognition results. Use asynchronous requests for audio data of any duration up to 80 minutes.

See: Speech Asynchronous Recognize

>>> import time
>>> operation = client.async_recognize(
...     None, 'gs://my-bucket/recording.flac',
...     'FLAC', 16000, max_alternatives=2)
>>> retry_count = 100
>>> while retry_count > 0 and not operation.complete:
...     retry_count -= 1
...     time.sleep(10)
...     operation.poll()  # API call
>>> operation.complete
True
>>> operation.results[0].transcript
'how old is the Brooklyn Bridge'
>>> operation.results[0].confidence
0.98267895

Synchronous Recognition

The sync_recognize() method converts speech data to text and returns alternative text transcriptons.

>>> alternatives = client.sync_recognize(
...     None, 'gs://my-bucket/recording.flac',
...     'FLAC', 16000, max_alternatives=2)
>>> for alternative in alternatives:
...     print('=' * 20)
...     print('transcript: ' + alternative['transcript'])
...     print('confidence: ' + alternative['confidence'])
====================
transcript: Hello, this is a test
confidence: 0.81
====================
transcript: Hello, this is one test
confidence: 0