Recognizers

Speech-to-Text V2 supports a Google Cloud resource called recognizers. Recognizers represent stored and reusable recognition configuration. You can use them to logically group together transcriptions or traffic for your application.

Before you begin

1. 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.

2. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

3. Make sure that billing is enabled for your Google Cloud project.

4. Enable the Speech-to-Text APIs.

   Enable the APIs

5. Make sure that you have the following role or roles on the project: Cloud Speech Administrator

   Check for the roles

   1. In the Google Cloud console, go to the IAM page.

      Go to IAM
   2. Select the project.

   3. 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.

   4. In the Role column for the row with your email address, check whether the list of roles includes the required roles.

   Grant the roles

   1. In the Google Cloud console, go to the IAM page.

      Go to IAM
   2. Select the project.
   3. Click Grant access.
   4. In the New principals field, enter your email address.
   5. In the Select a role list, select a role.
   6. To grant additional roles, click Add another role and add each additional role.
   7. Click Save.
6. Install the Google Cloud CLI.

7. To initialize the gcloud CLI, run the following command:

   gcloud init

   Note: If you installed the gcloud CLI previously, make sure you have the latest version by running gcloud components update.

8. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

9. Make sure that billing is enabled for your Google Cloud project.

10. Enable the Speech-to-Text APIs.

    Enable the APIs

11. Make sure that you have the following role or roles on the project: Cloud Speech Administrator

    Check for the roles

    1. In the Google Cloud console, go to the IAM page.

       Go to IAM
    2. Select the project.

    3. 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.

    4. In the Role column for the row with your email address, check whether the list of roles includes the required roles.

    Grant the roles

    1. In the Google Cloud console, go to the IAM page.

       Go to IAM
    2. Select the project.
    3. Click Grant access.
    4. In the New principals field, enter your email address.
    5. In the Select a role list, select a role.
    6. To grant additional roles, click Add another role and add each additional role.
    7. Click Save.
12. Install the Google Cloud CLI.

13. To initialize the gcloud CLI, run the following command:

    gcloud init

    Note: If you installed the gcloud CLI previously, make sure you have the latest version by running gcloud components update.

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.

14. Create local authentication credentials for your Google Account:

    gcloud auth application-default login

Also ensure you have installed the client library.

Understand recognizers

Recognizers are configurable, reusable recognition configurations. Creating recognizers with frequently used recognition configuration helps to simplify and reduce the size of recognition requests.

The core element of a recognizer is its default configuration. This is the configuration for every recognition request that this recognizer performs. You can override this default per request. Keep the default configuration for features you need across requests for a given recognizer, while overriding specific features for specific requests.

Reuse recognizers as often as possible. Creating one for each request dramatically increases the latency of your application and consumes your resource quotas. Create them infrequently during integration and setup, then reuse them for recognition requests.

Create recognizers

Here is an example of creating a recognizer that can be used to send recognition requests:

Python

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech


def create_recognizer(project_id: str, recognizer_id: str) -> cloud_speech.Recognizer:
    # Instantiates a client
    client = SpeechClient()

    request = cloud_speech.CreateRecognizerRequest(
        parent=f"projects/{project_id}/locations/global",
        recognizer_id=recognizer_id,
        recognizer=cloud_speech.Recognizer(
            default_recognition_config=cloud_speech.RecognitionConfig(
                language_codes=["en-US"], model="long"
            ),
        ),
    )

    operation = client.create_recognizer(request=request)
    recognizer = operation.result()

    print("Created Recognizer:", recognizer.name)
    return recognizer

Use an existing recognizer to send requests

Here is an example of sending multiple recognition requests using the same recognizer:

Python

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech


def transcribe_reuse_recognizer(
    project_id: str,
    recognizer_id: str,
    audio_file: str,
) -> cloud_speech.RecognizeResponse:
    """Transcribe an audio file using an existing recognizer."""
    # Instantiates a client
    client = SpeechClient()

    # Reads a file as bytes
    with open(audio_file, "rb") as f:
        content = f.read()

    request = cloud_speech.RecognizeRequest(
        recognizer=f"projects/{project_id}/locations/global/recognizers/{recognizer_id}",
        content=content,
    )

    # Transcribes the audio into text
    response = client.recognize(request=request)

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

    return response

Enable features in a recognizer

Recognizers can be used to enable various features in recognition, such as automatic punctuation or profanity filtering.

Here is an example of enabling automatic punctuation in a recognizer, which enables automatic punctuation in the recognition request using this recognizer:

Note: Samples throughout the documentation repeatedly illustrate creating recognizers. However, you should create them infrequently and reuse them often.

Python

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech


def transcribe_feature_in_recognizer(
    project_id: str,
    recognizer_id: str,
    audio_file: str,
) -> cloud_speech.RecognizeResponse:
    """Transcribe an audio file using an existing recognizer."""
    # Instantiates a client
    client = SpeechClient()

    request = cloud_speech.CreateRecognizerRequest(
        parent=f"projects/{project_id}/locations/global",
        recognizer_id=recognizer_id,
        recognizer=cloud_speech.Recognizer(
            default_recognition_config=cloud_speech.RecognitionConfig(
                auto_decoding_config=cloud_speech.AutoDetectDecodingConfig(),
                language_codes=["en-US"],
                model="latest_long",
                features=cloud_speech.RecognitionFeatures(
                    enable_automatic_punctuation=True,
                ),
            ),
        ),
    )

    operation = client.create_recognizer(request=request)
    recognizer = operation.result()

    print("Created Recognizer:", recognizer.name)

    # Reads a file as bytes
    with open(audio_file, "rb") as f:
        content = f.read()

    request = cloud_speech.RecognizeRequest(
        recognizer=f"projects/{project_id}/locations/global/recognizers/{recognizer_id}",
        content=content,
    )

    # Transcribes the audio into text
    response = client.recognize(request=request)

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

    return response

Override recognizer features in recognition requests

Here is an example of enabling multiple features in a recognizer, but disabling automatic punctuation for this recognition request:

Python

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech
from google.protobuf.field_mask_pb2 import FieldMask


def transcribe_override_recognizer(
    project_id: str,
    recognizer_id: str,
    audio_file: str,
) -> cloud_speech.RecognizeResponse:
    """Transcribe an audio file using an existing recognizer."""
    # Instantiates a client
    client = SpeechClient()

    request = cloud_speech.CreateRecognizerRequest(
        parent=f"projects/{project_id}/locations/global",
        recognizer_id=recognizer_id,
        recognizer=cloud_speech.Recognizer(
            default_recognition_config=cloud_speech.RecognitionConfig(
                auto_decoding_config=cloud_speech.AutoDetectDecodingConfig(),
                language_codes=["en-US"],
                model="latest_long",
                features=cloud_speech.RecognitionFeatures(
                    enable_automatic_punctuation=True,
                    enable_word_time_offsets=True,
                ),
            ),
        ),
    )

    operation = client.create_recognizer(request=request)
    recognizer = operation.result()

    print("Created Recognizer:", recognizer.name)

    # Reads a file as bytes
    with open(audio_file, "rb") as f:
        content = f.read()

    request = cloud_speech.RecognizeRequest(
        recognizer=f"projects/{project_id}/locations/global/recognizers/{recognizer_id}",
        config=cloud_speech.RecognitionConfig(
            features=cloud_speech.RecognitionFeatures(
                enable_word_time_offsets=False,
            ),
        ),
        config_mask=FieldMask(paths=["features.enable_word_time_offsets"]),
        content=content,
    )

    # Transcribes the audio into text
    response = client.recognize(request=request)

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

    return response

Send requests without recognizers

Recognizers are optional in recognition requests. To make a request without a recognizer, simply use the recognizer resource ID _ in the location you are making a request. Here is an example:

Python

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech


def quickstart_v2(
    project_id: str,
    audio_file: str,
) -> cloud_speech.RecognizeResponse:
    """Transcribe an audio file."""
    # Instantiates a client
    client = SpeechClient()

    # Reads a file as bytes
    with open(audio_file, "rb") as f:
        content = f.read()

    config = cloud_speech.RecognitionConfig(
        auto_decoding_config=cloud_speech.AutoDetectDecodingConfig(),
        language_codes=["en-US"],
        model="long",
    )

    request = cloud_speech.RecognizeRequest(
        recognizer=f"projects/{project_id}/locations/global/recognizers/_",
        config=config,
        content=content,
    )

    # Transcribes the audio into text
    response = client.recognize(request=request)

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

    return response

Clean up

To avoid incurring charges to your Google Cloud account for the resources used on this page, follow these steps.

1. Optional: Revoke the authentication credentials that you created, and delete the local credential file.

   gcloud auth application-default revoke

2. Optional: Revoke credentials from the gcloud CLI.

   gcloud auth revoke

Console

Caution: Deleting a project has the following effects:

• Everything in the project is deleted. If you used an existing project for the tasks in this document, when you delete it, you also delete any other work you've done in the project.
• Custom project IDs are lost. When you created this project, you might have created a custom project ID that you want to use in the future. To preserve the URLs that use the project ID, such as an appspot.com URL, delete selected resources inside the project instead of deleting the whole project.

If you plan to explore multiple architectures, tutorials, or quickstarts, reusing projects can help you avoid exceeding project quota limits.

In the Google Cloud console, go to the Manage resources page.

Go to Manage resources

In the project list, select the project that you want to delete, and then click Delete.

In the dialog, type the project ID, and then click Shut down to delete the project.

gcloud

Caution: Deleting a project has the following effects:

• Everything in the project is deleted. If you used an existing project for the tasks in this document, when you delete it, you also delete any other work you've done in the project.
• Custom project IDs are lost. When you created this project, you might have created a custom project ID that you want to use in the future. To preserve the URLs that use the project ID, such as an appspot.com URL, delete selected resources inside the project instead of deleting the whole project.

If you plan to explore multiple architectures, tutorials, or quickstarts, reusing projects can help you avoid exceeding project quota limits.

Delete a Google Cloud project:

gcloud projects delete PROJECT_ID

What's next

• Practice transcribing short audio files.
• Learn how to transcribe streaming audio.
• Learn how to transcribe long audio files.
• For best performance, accuracy, and other tips, see the best practices documentation.