将流式音频翻译成文本

Media Translation 可将音频文件或语音流翻译为另一种语言的文本。本页面提供的代码示例展示了如何使用 Media Translation 客户端库将流式音频翻译成文本。

设置项目

在使用 Media Translation 之前,您需要先设置一个 Google Cloud 项目,并为该项目启用 Media Translation API。

  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.

    Go to project selector

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

  4. Enable the Media Translation API.

    Enable the API

  5. Create a service account:

    1. In the Google Cloud console, go to the Create service account page.

      Go to Create service account
    2. Select your project.
    3. In the Service account name field, enter a name. The Google Cloud console fills in the Service account ID field based on this name.

      In the Service account description field, enter a description. For example, Service account for quickstart.

    4. Click Create and continue.
    5. Grant the Project > Owner role to the service account.

      To grant the role, find the Select a role list, then select Project > Owner.

    6. Click Continue.
    7. Click Done to finish creating the service account.

      Do not close your browser window. You will use it in the next step.

  6. Create a service account key:

    1. In the Google Cloud console, click the email address for the service account that you created.
    2. Click Keys.
    3. Click Add key, and then click Create new key.
    4. Click Create. A JSON key file is downloaded to your computer.
    5. Click Close.
  7. Set the environment variable GOOGLE_APPLICATION_CREDENTIALS to the path of the JSON file that contains your credentials. This variable applies only to your current shell session, so if you open a new session, set the variable again.

  8. Install the Google Cloud CLI.
  9. To initialize the gcloud CLI, run the following command:

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

    Go to project selector

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

  12. Enable the Media Translation API.

    Enable the API

  13. Create a service account:

    1. In the Google Cloud console, go to the Create service account page.

      Go to Create service account
    2. Select your project.
    3. In the Service account name field, enter a name. The Google Cloud console fills in the Service account ID field based on this name.

      In the Service account description field, enter a description. For example, Service account for quickstart.

    4. Click Create and continue.
    5. Grant the Project > Owner role to the service account.

      To grant the role, find the Select a role list, then select Project > Owner.

    6. Click Continue.
    7. Click Done to finish creating the service account.

      Do not close your browser window. You will use it in the next step.

  14. Create a service account key:

    1. In the Google Cloud console, click the email address for the service account that you created.
    2. Click Keys.
    3. Click Add key, and then click Create new key.
    4. Click Create. A JSON key file is downloaded to your computer.
    5. Click Close.
  15. Set the environment variable GOOGLE_APPLICATION_CREDENTIALS to the path of the JSON file that contains your credentials. This variable applies only to your current shell session, so if you open a new session, set the variable again.

  16. Install the Google Cloud CLI.
  17. To initialize the gcloud CLI, run the following command:

    gcloud init
  18. 根据您的首选语言安装客户端库

翻译语音内容

以下代码示例展示了如何翻译通过包含最长五分钟音频的文件或直播麦克风采集到的语音。如需有关如何提供语音数据以取得最佳识别准确率的建议,请参阅最佳做法

无论音频源如何,主要操作步骤都是相同的:

  1. 初始化一个 SpeechTranslationServiceClient 客户端,以用于向 Media Translation 发送请求。

    您可以使用同一个客户端重复发出多个请求。

  2. 创建一个 StreamingTranslateSpeechConfig 请求对象,以指定如何处理音频。

    StreamingTranslateSpeechConfig 对象包含一个 TranslateSpeechConfig 对象(提供有关音频源文件的信息)和一个 single_utterance 标志(用于指定在讲话人暂停讲话时,Media Translation 是否继续执行翻译)。

    TranslateSpeechConfig 对象提供音频源的技术规范(例如其编码和采样率)、设置翻译的源语言和目标语言(使用相应的 BCP-47 语言代码指定),并定义 Media Translation 使用何种翻译模型处理转录。

  3. 发送一系列 StreamingTranslateSpeechRequest 请求对象。

    您需要为待翻译的每个音频文件发送一系列请求。 第一个请求提供请求的 StreamingTranslateSpeechConfig 对象,随后的请求则以流式传输方式提供音频内容。

  4. 接收 StreamingTranslateSpeechResult 响应对象。

    虽然会接收 text_translation_result.is_final 值为 false 的任何响应,但最新的翻译结果会覆盖上一个结果。

    当 Media Translation 生成最终结果时,text_translation_result.is_final 字段设置为 true,后续收到的任何翻译结果都会附加到上一个结果之后。(在本例中不会覆盖上一个结果)。您可以输出完成的翻译,并从新的部分开始,处理下一部分转录和相应音频。

    当讲话人停止时,如果 single_utterance 请求对象中的 StreamingTranslateSpeechConfig 字段设为 true,Media Translation 将为响应中的 speech_event_type 事件返回 END_OF_SINGLE_UTTERANCE 事件。客户端将停止发送请求,但仍会继续接收响应,直到翻译完成。

  5. 流式传输的时长上限为 5 分钟。如果超出此上限,系统将返回 OUT_OF_RANGE 错误。

代码示例

翻译音频文件中的语音内容

Java

如需了解如何安装和使用 Media Translation 客户端库,请参阅 Media Translation 客户端库。 如需了解详情,请参阅 Media Translation Java API 参考文档

如需向 Media Translation 进行身份验证,请设置应用默认凭据。如需了解详情,请参阅为本地开发环境设置身份验证


import com.google.api.gax.rpc.BidiStream;
import com.google.cloud.mediatranslation.v1beta1.SpeechTranslationServiceClient;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechConfig;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechRequest;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechResponse;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechResult;
import com.google.cloud.mediatranslation.v1beta1.TranslateSpeechConfig;
import com.google.protobuf.ByteString;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class TranslateFromFile {

  public static void translateFromFile() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String filePath = "path/to/audio.raw";
    translateFromFile(filePath);
  }

  public static void translateFromFile(String filePath) throws IOException {
    // Initialize client that will be used to send requests. This client only needs to be created
    // once, and can be reused for multiple requests. After completing all of your requests, call
    // the "close" method on the client to safely clean up any remaining background resources.
    try (SpeechTranslationServiceClient client = SpeechTranslationServiceClient.create()) {
      Path path = Paths.get(filePath);
      byte[] content = Files.readAllBytes(path);
      ByteString audioContent = ByteString.copyFrom(content);

      TranslateSpeechConfig audioConfig =
          TranslateSpeechConfig.newBuilder()
              .setAudioEncoding("linear16")
              .setSampleRateHertz(16000)
              .setSourceLanguageCode("en-US")
              .setTargetLanguageCode("fr-FR")
              .build();

      StreamingTranslateSpeechConfig config =
          StreamingTranslateSpeechConfig.newBuilder()
              .setAudioConfig(audioConfig)
              .setSingleUtterance(true)
              .build();

      BidiStream<StreamingTranslateSpeechRequest, StreamingTranslateSpeechResponse> bidiStream =
          client.streamingTranslateSpeechCallable().call();

      // The first request contains the configuration.
      StreamingTranslateSpeechRequest requestConfig =
          StreamingTranslateSpeechRequest.newBuilder().setStreamingConfig(config).build();

      // The second request contains the audio
      StreamingTranslateSpeechRequest request =
          StreamingTranslateSpeechRequest.newBuilder().setAudioContent(audioContent).build();

      bidiStream.send(requestConfig);
      bidiStream.send(request);

      for (StreamingTranslateSpeechResponse response : bidiStream) {
        // Once the transcription settles, the response contains the
        // is_final result. The other results will be for subsequent portions of
        // the audio.
        StreamingTranslateSpeechResult res = response.getResult();
        String translation = res.getTextTranslationResult().getTranslation();

        if (res.getTextTranslationResult().getIsFinal()) {
          System.out.println(String.format("\nFinal translation: %s", translation));
          break;
        }
        System.out.println(String.format("\nPartial translation: %s", translation));
      }
    }
  }
}

Node.js

如需了解如何安装和使用 Media Translation 客户端库,请参阅 Media Translation 客户端库。 如需了解详情,请参阅 Media Translation Node.js API 参考文档

如需向 Media Translation 进行身份验证,请设置应用默认凭据。如需了解详情,请参阅为本地开发环境设置身份验证

const fs = require('fs');

// Imports the CLoud Media Translation client library
const {
  SpeechTranslationServiceClient,
} = require('@google-cloud/media-translation');

// Creates a client
const client = new SpeechTranslationServiceClient();

async function translate_from_file() {
  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  // const filename = 'Local path to audio file, e.g. /path/to/audio.raw';
  // const encoding = 'Encoding of the audio file, e.g. LINEAR16';
  // const sourceLanguage = 'BCP-47 source language code, e.g. en-US';
  // const targetLanguage = 'BCP-47 target language code, e.g. es-ES';

  const config = {
    audioConfig: {
      audioEncoding: encoding,
      sourceLanguageCode: sourceLanguage,
      targetLanguageCode: targetLanguage,
    },
    single_utterance: true,
  };

  // First request needs to have only a streaming config, no data.
  const initialRequest = {
    streamingConfig: config,
    audioContent: null,
  };

  const readStream = fs.createReadStream(filename, {
    highWaterMark: 4096,
    encoding: 'base64',
  });

  const chunks = [];
  readStream
    .on('data', chunk => {
      const request = {
        streamingConfig: config,
        audioContent: chunk.toString(),
      };
      chunks.push(request);
    })
    .on('close', () => {
      // Config-only request should be first in stream of requests
      stream.write(initialRequest);
      for (let i = 0; i < chunks.length; i++) {
        stream.write(chunks[i]);
      }
      stream.end();
    });

  const stream = client.streamingTranslateSpeech().on('data', response => {
    const {result} = response;
    if (result.textTranslationResult.isFinal) {
      console.log(
        `\nFinal translation: ${result.textTranslationResult.translation}`
      );
      console.log(`Final recognition result: ${result.recognitionResult}`);
    } else {
      console.log(
        `\nPartial translation: ${result.textTranslationResult.translation}`
      );
      console.log(`Partial recognition result: ${result.recognitionResult}`);
    }
  });

Python

如需了解如何安装和使用 Media Translation 客户端库,请参阅 Media Translation 客户端库。 如需了解详情,请参阅 Media Translation Python API 参考文档

如需向 Media Translation 进行身份验证,请设置应用默认凭据。如需了解详情,请参阅为本地开发环境设置身份验证

from google.cloud import mediatranslation


def translate_from_file(file_path="path/to/your/file"):
    client = mediatranslation.SpeechTranslationServiceClient()

    # The `sample_rate_hertz` field is not required for FLAC and WAV (Linear16)
    # encoded data. Other audio encodings must provide the sampling rate.
    audio_config = mediatranslation.TranslateSpeechConfig(
        audio_encoding="linear16",
        source_language_code="en-US",
        target_language_code="fr-FR",
    )

    streaming_config = mediatranslation.StreamingTranslateSpeechConfig(
        audio_config=audio_config, single_utterance=True
    )

    def request_generator(config, audio_file_path):
        # The first request contains the configuration.
        # Note that audio_content is explicitly set to None.
        yield mediatranslation.StreamingTranslateSpeechRequest(streaming_config=config)

        with open(audio_file_path, "rb") as audio:
            while True:
                chunk = audio.read(4096)
                if not chunk:
                    break
                yield mediatranslation.StreamingTranslateSpeechRequest(
                    audio_content=chunk
                )

    requests = request_generator(streaming_config, file_path)
    responses = client.streaming_translate_speech(requests)

    for response in responses:
        # Once the transcription settles, the response contains the
        # is_final result. The other results will be for subsequent portions of
        # the audio.
        print(f"Response: {response}")
        result = response.result
        translation = result.text_translation_result.translation

        if result.text_translation_result.is_final:
            print(f"\nFinal translation: {translation}")
            break

        print(f"\nPartial translation: {translation}")

翻译麦克风中的语音内容

Java

如需了解如何安装和使用 Media Translation 客户端库,请参阅 Media Translation 客户端库。 如需了解详情,请参阅 Media Translation Java API 参考文档

如需向 Media Translation 进行身份验证,请设置应用默认凭据。如需了解详情,请参阅为本地开发环境设置身份验证


import com.google.api.gax.rpc.ClientStream;
import com.google.api.gax.rpc.ResponseObserver;
import com.google.api.gax.rpc.StreamController;
import com.google.cloud.mediatranslation.v1beta1.SpeechTranslationServiceClient;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechConfig;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechRequest;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechResponse;
import com.google.cloud.mediatranslation.v1beta1.StreamingTranslateSpeechResult;
import com.google.cloud.mediatranslation.v1beta1.TranslateSpeechConfig;
import com.google.protobuf.ByteString;
import java.io.IOException;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.TargetDataLine;

public class TranslateFromMic {

  public static void main(String[] args) throws IOException, LineUnavailableException {
    translateFromMic();
  }

  public static void translateFromMic() throws IOException, LineUnavailableException {

    ResponseObserver<StreamingTranslateSpeechResponse> responseObserver = null;

    // Initialize client that will be used to send requests. This client only needs to be created
    // once, and can be reused for multiple requests. After completing all of your requests, call
    // the "close" method on the client to safely clean up any remaining background resources.
    try (SpeechTranslationServiceClient client = SpeechTranslationServiceClient.create()) {
      responseObserver =
          new ResponseObserver<StreamingTranslateSpeechResponse>() {

            @Override
            public void onStart(StreamController controller) {}

            @Override
            public void onResponse(StreamingTranslateSpeechResponse response) {
              StreamingTranslateSpeechResult res = response.getResult();
              String translation = res.getTextTranslationResult().getTranslation();

              if (res.getTextTranslationResult().getIsFinal()) {
                System.out.println(String.format("\nFinal translation: %s", translation));
              } else {
                System.out.println(String.format("\nPartial translation: %s", translation));
              }
            }

            @Override
            public void onComplete() {}

            public void onError(Throwable t) {
              System.out.println(t);
            }
          };

      ClientStream<StreamingTranslateSpeechRequest> clientStream =
          client.streamingTranslateSpeechCallable().splitCall(responseObserver);

      TranslateSpeechConfig audioConfig =
          TranslateSpeechConfig.newBuilder()
              .setAudioEncoding("linear16")
              .setSourceLanguageCode("en-US")
              .setTargetLanguageCode("es-ES")
              .setSampleRateHertz(16000)
              .build();

      StreamingTranslateSpeechConfig streamingRecognitionConfig =
          StreamingTranslateSpeechConfig.newBuilder().setAudioConfig(audioConfig).build();

      StreamingTranslateSpeechRequest request =
          StreamingTranslateSpeechRequest.newBuilder()
              .setStreamingConfig(streamingRecognitionConfig)
              .build(); // The first request in a streaming call has to be a config

      clientStream.send(request);
      // SampleRate:16000Hz, SampleSizeInBits: 16, Number of channels: 1, Signed: true,
      // bigEndian: false
      AudioFormat audioFormat = new AudioFormat(16000, 16, 1, true, false);
      DataLine.Info targetInfo =
          new DataLine.Info(
              TargetDataLine.class,
              audioFormat); // Set the system information to read from the microphone audio stream

      if (!AudioSystem.isLineSupported(targetInfo)) {
        System.out.println("Microphone not supported");
        System.exit(0);
      }
      // Target data line captures the audio stream the microphone produces.
      TargetDataLine targetDataLine = (TargetDataLine) AudioSystem.getLine(targetInfo);
      targetDataLine.open(audioFormat);
      targetDataLine.start();
      System.out.println("Start speaking... Press Ctrl-C to stop");
      long startTime = System.currentTimeMillis();
      // Audio Input Stream
      AudioInputStream audio = new AudioInputStream(targetDataLine);

      while (true) {
        byte[] data = new byte[6400];
        audio.read(data);
        request =
            StreamingTranslateSpeechRequest.newBuilder()
                .setAudioContent(ByteString.copyFrom(data))
                .build();
        clientStream.send(request);
      }
    }
  }
}

Node.js

如需了解如何安装和使用 Media Translation 客户端库,请参阅 Media Translation 客户端库。 如需了解详情,请参阅 Media Translation Node.js API 参考文档

如需向 Media Translation 进行身份验证,请设置应用默认凭据。如需了解详情,请参阅为本地开发环境设置身份验证


// Allow user input from terminal
const readline = require('readline');

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

function doTranslationLoop() {
  rl.question("Press any key to translate or 'q' to quit: ", answer => {
    if (answer.toLowerCase() === 'q') {
      rl.close();
    } else {
      translateFromMicrophone();
    }
  });
}

// Node-Record-lpcm16
const recorder = require('node-record-lpcm16');

// Imports the Cloud Media Translation client library
const {
  SpeechTranslationServiceClient,
} = require('@google-cloud/media-translation');

// Creates a client
const client = new SpeechTranslationServiceClient();

function translateFromMicrophone() {
  /**
   * TODO(developer): Uncomment the following lines before running the sample.
   */
  //const encoding = 'linear16';
  //const sampleRateHertz = 16000;
  //const sourceLanguage = 'Language to translate from, as BCP-47 locale';
  //const targetLanguage = 'Language to translate to, as BCP-47 locale';
  console.log('Begin speaking ...');

  const config = {
    audioConfig: {
      audioEncoding: encoding,
      sourceLanguageCode: sourceLanguage,
      targetLanguageCode: targetLanguage,
    },
    singleUtterance: true,
  };

  // First request needs to have only a streaming config, no data.
  const initialRequest = {
    streamingConfig: config,
    audioContent: null,
  };

  let currentTranslation = '';
  let currentRecognition = '';
  // Create a recognize stream
  const stream = client
    .streamingTranslateSpeech()
    .on('error', e => {
      if (e.code && e.code === 4) {
        console.log('Streaming translation reached its deadline.');
      } else {
        console.log(e);
      }
    })
    .on('data', response => {
      const {result, speechEventType} = response;
      if (speechEventType === 'END_OF_SINGLE_UTTERANCE') {
        console.log(`\nFinal translation: ${currentTranslation}`);
        console.log(`Final recognition result: ${currentRecognition}`);

        stream.destroy();
        recording.stop();
      } else {
        currentTranslation = result.textTranslationResult.translation;
        currentRecognition = result.recognitionResult;
        console.log(`\nPartial translation: ${currentTranslation}`);
        console.log(`Partial recognition result: ${currentRecognition}`);
      }
    });

  let isFirst = true;
  // Start recording and send microphone input to the Media Translation API
  const recording = recorder.record({
    sampleRateHertz: sampleRateHertz,
    threshold: 0, //silence threshold
    recordProgram: 'rec',
    silence: '5.0', //seconds of silence before ending
  });
  recording
    .stream()
    .on('data', chunk => {
      if (isFirst) {
        stream.write(initialRequest);
        isFirst = false;
      }
      const request = {
        streamingConfig: config,
        audioContent: chunk.toString('base64'),
      };
      if (!stream.destroyed) {
        stream.write(request);
      }
    })
    .on('close', () => {
      doTranslationLoop();
    });
}

doTranslationLoop();

Python

如需了解如何安装和使用 Media Translation 客户端库,请参阅 Media Translation 客户端库。 如需了解详情,请参阅 Media Translation Python API 参考文档

如需向 Media Translation 进行身份验证,请设置应用默认凭据。如需了解详情,请参阅为本地开发环境设置身份验证


import itertools
import queue

from google.cloud import mediatranslation as media
import pyaudio

# Audio recording parameters
RATE = 16000
CHUNK = int(RATE / 10)  # 100ms
SpeechEventType = media.StreamingTranslateSpeechResponse.SpeechEventType


class MicrophoneStream:
    """Opens a recording stream as a generator yielding the audio chunks."""

    def __init__(self, rate, chunk):
        self._rate = rate
        self._chunk = chunk

        # Create a thread-safe buffer of audio data
        self._buff = queue.Queue()
        self.closed = True

    def __enter__(self):
        self._audio_interface = pyaudio.PyAudio()
        self._audio_stream = self._audio_interface.open(
            format=pyaudio.paInt16,
            channels=1,
            rate=self._rate,
            input=True,
            frames_per_buffer=self._chunk,
            # Run the audio stream asynchronously to fill the buffer object.
            # This is necessary so that the input device's buffer doesn't
            # overflow while the calling thread makes network requests, etc.
            stream_callback=self._fill_buffer,
        )

        self.closed = False

        return self

    def __exit__(self, type=None, value=None, traceback=None):
        self._audio_stream.stop_stream()
        self._audio_stream.close()
        self.closed = True
        # Signal the generator to terminate so that the client's
        # streaming_recognize method will not block the process termination.
        self._buff.put(None)
        self._audio_interface.terminate()

    def _fill_buffer(self, in_data, frame_count, time_info, status_flags):
        """Continuously collect data from the audio stream, into the buffer."""
        self._buff.put(in_data)
        return None, pyaudio.paContinue

    def exit(self):
        self.__exit__()

    def generator(self):
        while not self.closed:
            # Use a blocking get() to ensure there's at least one chunk of
            # data, and stop iteration if the chunk is None, indicating the
            # end of the audio stream.
            chunk = self._buff.get()
            if chunk is None:
                return
            data = [chunk]

            # Now consume whatever other data's still buffered.
            while True:
                try:
                    chunk = self._buff.get(block=False)
                    if chunk is None:
                        return
                    data.append(chunk)
                except queue.Empty:
                    break

            yield b"".join(data)


def listen_print_loop(responses):
    """Iterates through server responses and prints them.

    The responses passed is a generator that will block until a response
    is provided by the server.
    """
    translation = ""
    for response in responses:
        # Once the transcription settles, the response contains the
        # END_OF_SINGLE_UTTERANCE event.
        if response.speech_event_type == SpeechEventType.END_OF_SINGLE_UTTERANCE:
            print(f"\nFinal translation: {translation}")
            return 0

        result = response.result
        translation = result.text_translation_result.translation

        print(f"\nPartial translation: {translation}")


def do_translation_loop():
    print("Begin speaking...")

    client = media.SpeechTranslationServiceClient()

    speech_config = media.TranslateSpeechConfig(
        audio_encoding="linear16",
        source_language_code="en-US",
        target_language_code="es-ES",
    )

    config = media.StreamingTranslateSpeechConfig(
        audio_config=speech_config, single_utterance=True
    )

    # The first request contains the configuration.
    # Note that audio_content is explicitly set to None.
    first_request = media.StreamingTranslateSpeechRequest(streaming_config=config)

    with MicrophoneStream(RATE, CHUNK) as stream:
        audio_generator = stream.generator()
        mic_requests = (
            media.StreamingTranslateSpeechRequest(audio_content=content)
            for content in audio_generator
        )

        requests = itertools.chain(iter([first_request]), mic_requests)

        responses = client.streaming_translate_speech(requests)

        # Print the translation responses as they arrive
        result = listen_print_loop(responses)
        if result == 0:
            stream.exit()


def main():
    while True:
        print()
        option = input("Press any key to translate or 'q' to quit: ")

        if option.lower() == "q":
            break

        do_translation_loop()


if __name__ == "__main__":
    main()