

Doc AWS SDK 예제 GitHub 리포지토리에서 더 많은 SDK 예제를 사용할 수 있습니다. [AWS](https://github.com/awsdocs/aws-doc-sdk-examples) 

기계 번역으로 제공되는 번역입니다. 제공된 번역과 원본 영어의 내용이 상충하는 경우에는 영어 버전이 우선합니다.

# AWS SDK와 `StartStreamTranscription` 함께 사용
<a name="transcribe-streaming_example_transcribe-streaming_StartStreamTranscription_section"></a>

다음 코드 예시는 `StartStreamTranscription`의 사용 방법을 보여 줍니다.

작업 예시는 대규모 프로그램에서 발췌한 코드이며 컨텍스트에 맞춰 실행해야 합니다. 다음 코드 예제에서는 컨텍스트 내에서 이 작업을 확인할 수 있습니다.
+  [오디오 파일 트랜스크립션](transcribe-streaming_example_transcribe-streaming_Scenario_StreamEvents_File_section.md) 
+  [마이크로 오디오 트랜스크립션](transcribe-streaming_example_transcribe-streaming_Scenario_StreamEvents_Microphone_section.md) 

------
#### [ C\$1\$1 ]

**SDK for C\$1\$1**  
 GitHub에 더 많은 내용이 있습니다. [AWS 코드 예 리포지토리](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/cpp/example_code/transcribe-streaming#code-examples)에서 전체 예를 찾고 설정 및 실행하는 방법을 배워보세요.

```
int main() {
    Aws::SDKOptions options;

    Aws::InitAPI(options);
    {
        //TODO(User): Set to the region of your AWS account.
        const Aws::String region = Aws::Region::US_WEST_2;

        //Load a profile that has been granted AmazonTranscribeFullAccess AWS managed permission policy.
        Aws::Client::ClientConfiguration config;
#ifdef _WIN32
        // ATTENTION: On Windows with the AWS C++ SDK, this example only runs if the SDK is built
        // with the curl library. 
        // For more information, see the accompanying ReadMe.
        // For more information, see "Building the SDK for Windows with curl".
        // https://docs.aws.amazon.com/sdk-for-cpp/v1/developer-guide/setup-windows.html
        //TODO(User): Update to the location of your .crt file.
        config.caFile = "C:/curl/bin/curl-ca-bundle.crt";
#endif
        config.region = region;

        TranscribeStreamingServiceClient client(config);
        StartStreamTranscriptionHandler handler;
        handler.SetOnErrorCallback(
                [](const Aws::Client::AWSError<TranscribeStreamingServiceErrors> &error) {
                        std::cerr << "ERROR: " + error.GetMessage() << std::endl;
                });
        //SetTranscriptEventCallback called for every 'chunk' of file transcripted.
        // Partial results are returned in real time.
        handler.SetTranscriptEventCallback([](const TranscriptEvent &ev) {
                for (auto &&r: ev.GetTranscript().GetResults()) {
                    if (r.GetIsPartial()) {
                        std::cout << "[partial] ";
                    }
                    else {
                        std::cout << "[Final] ";
                    }
                    for (auto &&alt: r.GetAlternatives()) {
                        std::cout << alt.GetTranscript() << std::endl;
                    }
                }
        });

        StartStreamTranscriptionRequest request;
        request.SetMediaSampleRateHertz(SAMPLE_RATE);
        request.SetLanguageCode(LanguageCode::en_US);
        request.SetMediaEncoding(
                MediaEncoding::pcm); // wav and aiff files are PCM formats.
        request.SetEventStreamHandler(handler);

        auto OnStreamReady = [](AudioStream &stream) {
                Aws::FStream file(FILE_NAME, std::ios_base::in | std::ios_base::binary);
                if (!file.is_open()) {
                    std::cerr << "Failed to open " << FILE_NAME << '\n';
                }
                std::array<char, BUFFER_SIZE> buf;
                int i = 0;
                while (file) {
                    file.read(&buf[0], buf.size());

                    if (!file)
                        std::cout << "File: only " << file.gcount() << " could be read"
                                  << std::endl;

                    Aws::Vector<unsigned char> bits{buf.begin(), buf.end()};
                    AudioEvent event(std::move(bits));
                    if (!stream) {
                        std::cerr << "Failed to create a stream" << std::endl;
                        break;
                    }
                    //The std::basic_istream::gcount() is used to count the characters in the given string. It returns
                    //the number of characters extracted by the last read() operation.
                    if (file.gcount() > 0) {
                        if (!stream.WriteAudioEvent(event)) {
                            std::cerr << "Failed to write an audio event" << std::endl;
                            break;
                        }
                    }
                    else {
                        break;
                    }
                    std::this_thread::sleep_for(std::chrono::milliseconds(
                            25)); // Slow down because we are streaming from a file.
                }
                if (!stream.WriteAudioEvent(
                        AudioEvent())) {
                    // Per the spec, we have to send an empty event (an event without a payload) at the end.
                    std::cerr << "Failed to send an empty frame" << std::endl;
                }
                else {
                    std::cout << "Successfully sent the empty frame" << std::endl;
                }
                stream.flush();
                stream.Close();
        };

        Aws::Utils::Threading::Semaphore signaling(0 /*initialCount*/, 1 /*maxCount*/);
        auto OnResponseCallback = [&signaling](
                const TranscribeStreamingServiceClient * /*unused*/,
                const Model::StartStreamTranscriptionRequest & /*unused*/,
                const Model::StartStreamTranscriptionOutcome &outcome,
                const std::shared_ptr<const Aws::Client::AsyncCallerContext> & /*unused*/) {

                if (!outcome.IsSuccess()) {
                    std::cerr << "Transcribe streaming error "
                              << outcome.GetError().GetMessage() << std::endl;
                }

                signaling.Release();
        };

        std::cout << "Starting..." << std::endl;
        client.StartStreamTranscriptionAsync(request, OnStreamReady, OnResponseCallback,
                                             nullptr /*context*/);
        signaling.WaitOne(); // Prevent the application from exiting until we're done.
        std::cout << "Done" << std::endl;
    }

    Aws::ShutdownAPI(options);

    return 0;
}
```
+  API 세부 정보는 *AWS SDK for C\$1\$1 API 참조*의 [StartStreamTranscription](https://docs.aws.amazon.com/goto/SdkForCpp/transcribe-streaming-2017-10-26/StartStreamTranscription)을 참조하세요.

------
#### [ Java ]

**SDK for Java 2.x**  
 GitHub에 더 많은 내용이 있습니다. [AWS 코드 예 리포지토리](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/transcribe-streaming#code-examples)에서 전체 예를 찾고 설정 및 실행하는 방법을 배워보세요.

```
public class TranscribeStreamingDemoApp {
    private static final Region REGION = Region.US_EAST_1;
    private static TranscribeStreamingAsyncClient client;

    public static void main(String[] args)
            throws URISyntaxException, ExecutionException, InterruptedException, LineUnavailableException {

        client = TranscribeStreamingAsyncClient.builder()
                .credentialsProvider(getCredentials())
                .region(REGION)
                .build();

        CompletableFuture<Void> result = client.startStreamTranscription(getRequest(16_000),
                new AudioStreamPublisher(getStreamFromMic()),
                getResponseHandler());

        result.get();
        client.close();
    }

    private static InputStream getStreamFromMic() throws LineUnavailableException {

        // Signed PCM AudioFormat with 16kHz, 16 bit sample size, mono
        int sampleRate = 16000;
        AudioFormat format = new AudioFormat(sampleRate, 16, 1, true, false);
        DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);

        if (!AudioSystem.isLineSupported(info)) {
            System.out.println("Line not supported");
            System.exit(0);
        }

        TargetDataLine line = (TargetDataLine) AudioSystem.getLine(info);
        line.open(format);
        line.start();

        InputStream audioStream = new AudioInputStream(line);
        return audioStream;
    }

    private static AwsCredentialsProvider getCredentials() {
        return DefaultCredentialsProvider.create();
    }

    private static StartStreamTranscriptionRequest getRequest(Integer mediaSampleRateHertz) {
        return StartStreamTranscriptionRequest.builder()
                .languageCode(LanguageCode.EN_US.toString())
                .mediaEncoding(MediaEncoding.PCM)
                .mediaSampleRateHertz(mediaSampleRateHertz)
                .build();
    }

    private static StartStreamTranscriptionResponseHandler getResponseHandler() {
        return StartStreamTranscriptionResponseHandler.builder()
                .onResponse(r -> {
                    System.out.println("Received Initial response");
                })
                .onError(e -> {
                    System.out.println(e.getMessage());
                    StringWriter sw = new StringWriter();
                    e.printStackTrace(new PrintWriter(sw));
                    System.out.println("Error Occurred: " + sw);
                })
                .onComplete(() -> {
                    System.out.println("=== All records stream successfully ===");
                })
                .subscriber(event -> {
                    List<Result> results = ((TranscriptEvent) event).transcript().results();
                    if (results.size() > 0) {
                        if (!results.get(0).alternatives().get(0).transcript().isEmpty()) {
                            System.out.println(results.get(0).alternatives().get(0).transcript());
                        }
                    }
                })
                .build();
    }

    
    private static class AudioStreamPublisher implements Publisher<AudioStream> {
        private static Subscription currentSubscription;
        private final InputStream inputStream;

        private AudioStreamPublisher(InputStream inputStream) {
            this.inputStream = inputStream;
        }

        @Override
        public void subscribe(Subscriber<? super AudioStream> s) {

            if (currentSubscription == null) {
                currentSubscription = new SubscriptionImpl(s, inputStream);
            } else {
                currentSubscription.cancel();
                currentSubscription = new SubscriptionImpl(s, inputStream);
            }
            s.onSubscribe(currentSubscription);
        }
    }

    public static class SubscriptionImpl implements Subscription {
        private static final int CHUNK_SIZE_IN_BYTES = 1024;
        private final Subscriber<? super AudioStream> subscriber;
        private final InputStream inputStream;
        private final ExecutorService executor = Executors.newFixedThreadPool(1);
        private final AtomicLong demand = new AtomicLong(0);

        SubscriptionImpl(Subscriber<? super AudioStream> s, InputStream inputStream) {
            this.subscriber = s;
            this.inputStream = inputStream;
        }

        @Override
        public void request(long n) {
            if (n <= 0) {
                subscriber.onError(new IllegalArgumentException("Demand must be positive"));
            }

            demand.getAndAdd(n);

            executor.submit(() -> {
                try {
                    do {
                        ByteBuffer audioBuffer = getNextEvent();
                        if (audioBuffer.remaining() > 0) {
                            AudioEvent audioEvent = audioEventFromBuffer(audioBuffer);
                            subscriber.onNext(audioEvent);
                        } else {
                            subscriber.onComplete();
                            break;
                        }
                    } while (demand.decrementAndGet() > 0);
                } catch (Exception e) {
                    subscriber.onError(e);
                }
            });
        }

        @Override
        public void cancel() {
            executor.shutdown();
        }

        private ByteBuffer getNextEvent() {
            ByteBuffer audioBuffer = null;
            byte[] audioBytes = new byte[CHUNK_SIZE_IN_BYTES];

            int len = 0;
            try {
                len = inputStream.read(audioBytes);

                if (len <= 0) {
                    audioBuffer = ByteBuffer.allocate(0);
                } else {
                    audioBuffer = ByteBuffer.wrap(audioBytes, 0, len);
                }
            } catch (IOException e) {
                throw new UncheckedIOException(e);
            }

            return audioBuffer;
        }

        private AudioEvent audioEventFromBuffer(ByteBuffer bb) {
            return AudioEvent.builder()
                    .audioChunk(SdkBytes.fromByteBuffer(bb))
                    .build();
        }
    }
}
```
+  API 세부 정보는 *AWS SDK for Java 2.x API 참조*의 [StartStreamTranscription](https://docs.aws.amazon.com/goto/SdkForJavaV2/transcribe-streaming-2017-10-26/StartStreamTranscription)을 참조하세요.

------
#### [ Swift ]

**SDK for Swift**  
 GitHub에 더 많은 내용이 있습니다. [AWS 코드 예 리포지토리](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/swift/example_code/transcribe-streaming#code-examples)에서 전체 예를 찾고 설정 및 실행하는 방법을 배워보세요.

```
        let client = TranscribeStreamingClient(
            config: try await TranscribeStreamingClient.TranscribeStreamingClientConfiguration(
                region: region
            )
        )

        // Start the transcription running on the audio stream.

        let output = try await client.startStreamTranscription(
            input: StartStreamTranscriptionInput(
                audioStream: try await createAudioStream(),
                languageCode: TranscribeStreamingClientTypes.LanguageCode(rawValue: lang),
                mediaEncoding: encoding,
                mediaSampleRateHertz: sampleRate
            )
        )
```
+  API 세부 정보는 *AWS SDK for Swift API 참조*의 [StartStreamTranscription](https://sdk.amazonaws.com/swift/api/awstranscribestreaming/latest/documentation/awstranscribestreaming/transcribestreamingclient/startstreamtranscription(input:))을 참조하세요.

------