Alibaba Cloud Model Studio:Paraformer real-time speech recognition Java SDK

Recognize speech from a microphone

import com.alibaba.dashscope.audio.asr.recognition.Recognition;
import com.alibaba.dashscope.audio.asr.recognition.RecognitionParam;
import com.alibaba.dashscope.audio.asr.recognition.RecognitionResult;
import com.alibaba.dashscope.common.ResultCallback;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.TargetDataLine;

import java.nio.ByteBuffer;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

public class Main {
    public static void main(String[] args) throws InterruptedException {
        ExecutorService executorService = Executors.newSingleThreadExecutor();
        executorService.submit(new RealtimeRecognitionTask());
        executorService.shutdown();
        executorService.awaitTermination(1, TimeUnit.MINUTES);
        System.exit(0);
    }
}

class RealtimeRecognitionTask implements Runnable {
    @Override
    public void run() {
        RecognitionParam param = RecognitionParam.builder()
                // If you do not configure the API Key to an environment variable, replace apiKey with your API Key.
                // .apiKey("yourApikey")
                .model("paraformer-realtime-v2")
                .format("wav")
                .sampleRate(16000)
                // The "language_hints" parameter is supported only by the paraformer-realtime-v2 model.
                .parameter("language_hints", new String[]{"zh", "en"})
                .build();
        Recognition recognizer = new Recognition();

        ResultCallback<RecognitionResult> callback = new ResultCallback<RecognitionResult>() {
            @Override
            public void onEvent(RecognitionResult result) {
                if (result.isSentenceEnd()) {
                    System.out.println("Final Result: " + result.getSentence().getText());
                } else {
                    System.out.println("Intermediate Result: " + result.getSentence().getText());
                }
            }

            @Override
            public void onComplete() {
                System.out.println("Recognition complete");
            }

            @Override
            public void onError(Exception e) {
                System.out.println("RecognitionCallback error: " + e.getMessage());
            }
        };
        try {
            recognizer.call(param, callback);
            // Create an audio format.
            AudioFormat audioFormat = new AudioFormat(16000, 16, 1, true, false);
            // Match the default recording device based on the format.
            TargetDataLine targetDataLine =
                    AudioSystem.getTargetDataLine(audioFormat);
            targetDataLine.open(audioFormat);
            // Start recording.
            targetDataLine.start();
            ByteBuffer buffer = ByteBuffer.allocate(1024);
            long start = System.currentTimeMillis();
            // Record for 50s and perform real-time transcription.
            while (System.currentTimeMillis() - start < 50000) {
                int read = targetDataLine.read(buffer.array(), 0, buffer.capacity());
                if (read > 0) {
                    buffer.limit(read);
                    // Send the recorded audio data to the streaming recognition service.
                    recognizer.sendAudioFrame(buffer);
                    buffer = ByteBuffer.allocate(1024);
                    // The recording rate is limited. Sleep for a short period to prevent high CPU usage.
                    Thread.sleep(20);
                }
            }
            recognizer.stop();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // Close the WebSocket connection after the task is complete.
            recognizer.getDuplexApi().close(1000, "bye");
        }

        System.out.println(
                "[Metric] requestId: "
                        + recognizer.getLastRequestId()
                        + ", first package delay ms: "
                        + recognizer.getFirstPackageDelay()
                        + ", last package delay ms: "
                        + recognizer.getLastPackageDelay());
    }
}

Recognize a local audio file

The audio file used in the example is: asr_example.wav.

import com.alibaba.dashscope.audio.asr.recognition.Recognition;
import com.alibaba.dashscope.audio.asr.recognition.RecognitionParam;
import com.alibaba.dashscope.audio.asr.recognition.RecognitionResult;
import com.alibaba.dashscope.common.ResultCallback;

import java.io.FileInputStream;
import java.nio.ByteBuffer;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

class TimeUtils {
    private static final DateTimeFormatter formatter =
            DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSS");

    public static String getTimestamp() {
        return LocalDateTime.now().format(formatter);
    }
}

public class Main {
    public static void main(String[] args) throws InterruptedException {
        ExecutorService executorService = Executors.newSingleThreadExecutor();
        executorService.submit(new RealtimeRecognitionTask(Paths.get(System.getProperty("user.dir"), "asr_example.wav")));
        executorService.shutdown();

        // wait for all tasks to complete
        executorService.awaitTermination(1, TimeUnit.MINUTES);
        System.exit(0);
    }
}

class RealtimeRecognitionTask implements Runnable {
    private Path filepath;

    public RealtimeRecognitionTask(Path filepath) {
        this.filepath = filepath;
    }

    @Override
    public void run() {
        RecognitionParam param = RecognitionParam.builder()
                // If you do not configure the API Key to an environment variable, replace apiKey with your API Key.
                // .apiKey("yourApikey")
                .model("paraformer-realtime-v2")
                .format("wav")
                .sampleRate(16000)
                // The "language_hints" parameter is supported only by the paraformer-realtime-v2 model.
                .parameter("language_hints", new String[]{"zh", "en"})
                .build();
        Recognition recognizer = new Recognition();

        String threadName = Thread.currentThread().getName();

        ResultCallback<RecognitionResult> callback = new ResultCallback<RecognitionResult>() {
            @Override
            public void onEvent(RecognitionResult message) {
                if (message.isSentenceEnd()) {

                    System.out.println(TimeUtils.getTimestamp()+" "+
                            "[process " + threadName + "] Final Result:" + message.getSentence().getText());
                } else {
                    System.out.println(TimeUtils.getTimestamp()+" "+
                            "[process " + threadName + "] Intermediate Result: " + message.getSentence().getText());
                }
            }

            @Override
            public void onComplete() {
                System.out.println(TimeUtils.getTimestamp()+" "+"[" + threadName + "] Recognition complete");
            }

            @Override
            public void onError(Exception e) {
                System.out.println(TimeUtils.getTimestamp()+" "+
                        "[" + threadName + "] RecognitionCallback error: " + e.getMessage());
            }
        };

        try {
            recognizer.call(param, callback);
            // Please replace the path with your audio file path.
            System.out.println(TimeUtils.getTimestamp()+" "+"[" + threadName + "] Input file_path is: " + this.filepath);
            // Read file and send audio by chunks.
            FileInputStream fis = new FileInputStream(this.filepath.toFile());
            // Set the chunk size to 1 second for a 16 kHz sample rate.
            byte[] buffer = new byte[3200];
            int bytesRead;
            // Loop to read chunks of the file.
            while ((bytesRead = fis.read(buffer)) != -1) {
                ByteBuffer byteBuffer;
                // Handle the last chunk which might be smaller than the buffer size.
                System.out.println(TimeUtils.getTimestamp()+" "+"[" + threadName + "] bytesRead: " + bytesRead);
                if (bytesRead < buffer.length) {
                    byteBuffer = ByteBuffer.wrap(buffer, 0, bytesRead);
                } else {
                    byteBuffer = ByteBuffer.wrap(buffer);
                }

                recognizer.sendAudioFrame(byteBuffer);
                buffer = new byte[3200];
                Thread.sleep(100);
            }
            System.out.println(TimeUtils.getTimestamp()+" "+LocalDateTime.now());
            recognizer.stop();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // Close the WebSocket connection after the task is complete.
            recognizer.getDuplexApi().close(1000, "bye");
        }

        System.out.println(
                "["
                        + threadName
                        + "][Metric] requestId: "
                        + recognizer.getLastRequestId()
                        + ", first package delay ms: "
                        + recognizer.getFirstPackageDelay()
                        + ", last package delay ms: "
                        + recognizer.getLastPackageDelay());
    }
}