This section demonstrates how to transcribe streaming audio, like the input from a microphone, to text.
Streaming speech recognition allows you to stream audio to Speech-to-Text and receive a stream speech recognition results in real time as the audio is processed. See also the audio limits for streaming speech recognition requests. Streaming speech recognition is available through gRPC only.
Before you begin
- Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.
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In the Google Cloud console, on the project selector page, select or create a Google Cloud project.
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Make sure that billing is enabled for your Google Cloud project.
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Enable the Speech-to-Text APIs.
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Make sure that you have the following role or roles on the project: Cloud Speech Administrator
Check for the roles
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In the Google Cloud console, go to the IAM page.
Go to IAM - Select the project.
-
In the Principal column, find the row that has your email address.
If your email address isn't in that column, then you do not have any roles.
- In the Role column for the row with your email address, check whether the list of roles includes the required roles.
Grant the roles
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In the Google Cloud console, go to the IAM page.
Go to IAM - Select the project.
- Click Grant access.
- In the New principals field, enter your email address.
- In the Select a role list, select a role.
- To grant additional roles, click Add another role and add each additional role.
- Click Save.
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- Install the Google Cloud CLI.
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To initialize the gcloud CLI, run the following command:
gcloud init
-
In the Google Cloud console, on the project selector page, select or create a Google Cloud project.
-
Make sure that billing is enabled for your Google Cloud project.
-
Enable the Speech-to-Text APIs.
-
Make sure that you have the following role or roles on the project: Cloud Speech Administrator
Check for the roles
-
In the Google Cloud console, go to the IAM page.
Go to IAM - Select the project.
-
In the Principal column, find the row that has your email address.
If your email address isn't in that column, then you do not have any roles.
- In the Role column for the row with your email address, check whether the list of roles includes the required roles.
Grant the roles
-
In the Google Cloud console, go to the IAM page.
Go to IAM - Select the project.
- Click Grant access.
- In the New principals field, enter your email address.
- In the Select a role list, select a role.
- To grant additional roles, click Add another role and add each additional role.
- Click Save.
-
- Install the Google Cloud CLI.
-
To initialize the gcloud CLI, run the following command:
gcloud init
-
Create local authentication credentials for your Google Account:
gcloud auth application-default login
Client libraries can use Application Default Credentials to easily authenticate with Google APIs and send requests to those APIs. With Application Default Credentials, you can test your application locally and deploy it without changing the underlying code. For more information, see Authenticate for using client libraries.
Also ensure you have installed the client library.
Perform streaming speech recognition on a local file
Below is an example of performing streaming speech recognition on a local audio
file. There is a 25 KB limit on audio sent in the requests of a stream. This
limit applies to to both the initial StreamingRecognize
request
and the size of each individual message in the stream. Exceeding this limit will
throw an error.
Python
While you can stream a local audio file to the Speech-to-Text API, it is recommended that you perform synchronous audio recognition.
Clean up
To avoid incurring charges to your Google Cloud account for the resources used on this page, follow these steps.
-
Optional: Revoke the authentication credentials that you created, and delete the local credential file.
gcloud auth application-default revoke
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Optional: Revoke credentials from the gcloud CLI.
gcloud auth revoke
Console
gcloud
Delete a Google Cloud project:
gcloud projects delete PROJECT_ID
What's next
- See the reference documentation for streaming recognition.
- Practice transcribing short audio files.
- Learn how to transcribe long audio files.
- Transcribe audio files using Chirp.
- For best performance, accuracy, and other tips, see the best practices documentation.