轉錄短音訊檔案

本頁面說明如何使用同步語音辨識功能，將短音訊檔案轉錄為文字。

同步語音辨識會傳回短音訊 (少於 60 秒) 的辨識文字。

您可以直接從本機檔案將音訊內容傳送至 Cloud Speech-to-Text，也可以讓 Cloud Speech-to-Text 處理Cloud Storage bucket 中儲存的音訊內容。如要瞭解同步語音辨識要求的限制，請參閱「配額與限制」頁面。

注意： 使用本機音訊檔案透過 API 傳送的所有要求，長度上限為 60 秒，大小上限為 10 MB，或兩者皆是。如果要求超出這段時間、大小或兩者，就會發生錯誤。詳情請參閱「配額與限制」頁面說明文件。

事前準備

登入 Google Cloud 帳戶。如果您是 Google Cloud新手，歡迎 建立帳戶，親自體驗產品的實際應用成效。新客戶還能獲得價值 $300 美元的免費抵免額，用於執行、測試及部署工作負載。

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

Roles required to select or create a project

• Select a project: Selecting a project doesn't require a specific IAM role—you can select any project that you've been granted a role on.
• Create a project: To create a project, you need the Project Creator role (roles/resourcemanager.projectCreator), which contains the resourcemanager.projects.create permission. Learn how to grant roles.

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

Verify that billing is enabled for your Google Cloud project.

Enable the Speech-to-Text APIs, if any are not already enabled.

Roles required to enable APIs

To enable APIs, you need the serviceusage.services.enable permission. If you created the project, then you likely already have this permission through the Owner role (roles/owner). Otherwise, you can get this permission through the Service Usage Admin role (roles/serviceusage.serviceUsageAdmin). Learn how to grant roles.

Enable the APIs

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 all rows that identify you or a group that you're included in. To learn which groups you're included in, contact your administrator.

4. For all rows that specify or include you, check the Role column to see 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 user identifier. This is typically the email address for a Google Account.

5. Click Select a role, then search for the role.
6. To grant additional roles, click Add another role and add each additional role.
7. Click Save.

Install the Google Cloud CLI.

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

If you're using an external identity provider (IdP), you must first sign in to the gcloud CLI with your federated identity.

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.

Roles required to select or create a project

• Select a project: Selecting a project doesn't require a specific IAM role—you can select any project that you've been granted a role on.
• Create a project: To create a project, you need the Project Creator role (roles/resourcemanager.projectCreator), which contains the resourcemanager.projects.create permission. Learn how to grant roles.

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

Verify that billing is enabled for your Google Cloud project.

Enable the Speech-to-Text APIs, if any are not already enabled.

Roles required to enable APIs

To enable APIs, you need the serviceusage.services.enable permission. If you created the project, then you likely already have this permission through the Owner role (roles/owner). Otherwise, you can get this permission through the Service Usage Admin role (roles/serviceusage.serviceUsageAdmin). Learn how to grant roles.

Enable the APIs

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 all rows that identify you or a group that you're included in. To learn which groups you're included in, contact your administrator.

4. For all rows that specify or include you, check the Role column to see 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 user identifier. This is typically the email address for a Google Account.

5. Click Select a role, then search for the role.
6. To grant additional roles, click Add another role and add each additional role.
7. Click Save.

Install the Google Cloud CLI.

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

If you're using an external identity provider (IdP), you must first sign in to the gcloud CLI with your federated identity.

To initialize the gcloud CLI, run the following command:

gcloud init

用戶端程式庫可以使用應用程式預設憑證，輕鬆向 Google API 進行驗證，並向這些 API 傳送要求。有了應用程式預設憑證，您可以在本機測試應用程式，並在不變更基礎程式碼的情況下部署應用程式。詳情請參閱「 進行驗證以使用用戶端程式庫」一文。

1. 如果您使用本機殼層，請為使用者帳戶建立本機驗證憑證：

   gcloud auth application-default login

   如果您使用 Cloud Shell，則不需要執行這項操作。

   如果系統傳回驗證錯誤，且您使用的是外部識別資訊提供者 (IdP)，請確認您已 使用聯合身分登入 gcloud CLI。

此外，請確認您已安裝用戶端程式庫。

對本機檔案執行同步語音辨識

以下是對本機音訊檔案執行同步語音辨識的範例：

Python

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

# TODO(developer): Update and un-comment below line
# PROJECT_ID = "your-project-id"

# Instantiates a client
client = SpeechClient()

# Reads a file as bytes
with open("resources/audio.wav", "rb") as f:
    audio_content = f.read()

config = cloud_speech.RecognitionConfig(
    auto_decoding_config=cloud_speech.AutoDetectDecodingConfig(),
    language_codes=["en-US"],
    model="chirp_3",
)

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

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

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

對遠端檔案執行同步語音辨識

為方便起見，Speech-to-Text API 可直接對 Cloud Storage 中的音訊檔案執行同步語音辨識，不必在要求主體中傳送音訊檔案內容。

Speech-to-Text 會使用服務帳戶存取 Cloud Storage 中的檔案。根據預設，服務帳戶可以存取同一專案中的 Cloud Storage 檔案。

服務帳戶電子郵件地址如下：

[e-mail]

如要轉錄其他專案中的 Cloud Storage 檔案，您可以將 [語音轉文字服務代理程式][speech-service-agent]角色授予其他專案中的這個服務帳戶：

gcloud projects add-iam-policy-binding PROJECT_ID \
    --member=serviceAccount:[e-mail] \
    --role=roles/speech.serviceAgent

如要進一步瞭解專案 IAM 政策，請參閱 [管理專案、資料夾和機構的存取權][manage-access]。

您也可以授予服務帳戶特定 Cloud Storage bucket 的權限，提供更精細的存取權：

gcloud storage buckets add-iam-policy-binding gs://BUCKET_NAME \
    --member=serviceAccount:[e-mail] \
    --role=roles/storage.admin

如要進一步瞭解如何管理 Cloud Storage 存取權，請參閱 Cloud Storage 說明文件中的「[建立及管理存取控制清單][buckets-manage-acl]」。

以下是對位於 Cloud Storage 中的檔案執行同步語音辨識的範例：

Python

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

# Instantiates a client
client = SpeechClient()

# TODO(developer): Update and un-comment below line
# PROJECT_ID = "your-project-id"

config = cloud_speech.RecognitionConfig(
    auto_decoding_config=cloud_speech.AutoDetectDecodingConfig(),
    language_codes=["en-US"],
    model="chirp_3",
)

request = cloud_speech.RecognizeRequest(
    recognizer=f"projects/{PROJECT_ID}/locations/global/recognizers/_",
    config=config,
    uri="gs://cloud-samples-data/speech/audio.flac",  # URI of the audio file in Google Cloud Storage
)

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

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

清除所用資源

為避免系統向您的 Google Cloud 帳戶收取本頁面所用資源的費用，請按照下列步驟操作。

1. 選用：撤銷您建立的驗證憑證，並刪除本機憑證檔案。

   gcloud auth application-default revoke

2. 選用：從 gcloud CLI 撤銷憑證。

   gcloud auth revoke

控制台

注意：刪除專案會有以下後果：

• 專案中的所有內容都會遭到刪除。如果使用現有專案來進行本文中的任務，刪除專案將一併移除當中已完成的其他任務'。
• 自訂專案 ID 會消失。當您之前建立這個專案時，可能建立了想要在日後使用的自訂專案 ID。如要保留使用該專案 ID 的網址 (例如 appspot.com 網址)，請刪除在該專案中選取的資源，而不是刪除整個專案。

如果打算探索多種架構、教學課程或快速入門導覽課程，重複使用專案可避免超出專案配額限制。

前往 Google Cloud 控制台的「Manage resources」(管理資源) 頁面。

前往「Manage resources」(管理資源)

在專案清單中選取要刪除的專案，然後點選「Delete」(刪除)。

在對話方塊中輸入專案 ID，然後按一下 [Shut down] (關閉) 以刪除專案。

gcloud

注意：刪除專案會有以下後果：

• 專案中的所有內容都會遭到刪除。如果使用現有專案來進行本文中的任務，刪除專案將一併移除當中已完成的其他任務'。
• 自訂專案 ID 會消失。當您之前建立這個專案時，可能建立了想要在日後使用的自訂專案 ID。如要保留使用該專案 ID 的網址 (例如 appspot.com 網址)，請刪除在該專案中選取的資源，而不是刪除整個專案。

如果打算探索多種架構、教學課程或快速入門導覽課程，重複使用專案可避免超出專案配額限制。

刪除 Google Cloud 專案：

gcloud projects delete PROJECT_ID

後續步驟

• 如需同步辨識，請參閱參考文件。
• 瞭解如何轉錄串流音訊。
• 瞭解如何轉錄長音訊檔案。
• 如要瞭解如何獲得最佳效能和準確度，以及其他提示，請參閱最佳做法說明文件。