Java實現文字轉語音

一、文字轉語音API介紹

近年來，隨著人工智慧技術的飛速發展，文字轉語音技術也日漸成熟。目前市面上已經出現了許多文字轉語音的API，其中最為知名的當屬百度AI開放平台、阿里雲智能語音等。這些API功能強大、使用方便，且還支持多種語言轉換，可以滿足各種場景的需求。

二、Java實現API調用

Java作為一種廣泛應用於企業開發的編程語言，自然也支持文字轉語音API的調用。以百度AI開放平台為例，需要先在官網進行註冊、申請API密鑰等操作，然後通過Java代碼調用介面進行文字轉語音。下面是示例代碼：

public class BaiduAiService{

    public static void main(String[] args) {
        String API_KEY = "your_api_key";
        String SECRET_KEY = "your_secret_key";
        // 初始化一個AipSpeech
        AipSpeech client = new AipSpeech(API_KEY, SECRET_KEY);

        // 調用介面轉換文字為語音
        TtsResponse res = client.synthesis("百度AI開放平台，讓AI變得簡單", "zh", 1, null);
        
        // 將語音轉換成文件保存
        FileOutputStream fos = new FileOutputStream(new File("out.mp3"));
        byte[] bytes = res.getData();
        fos.write(bytes, 0, bytes.length);
        fos.flush();
        fos.close();
    }
}

三、Java實現本地語音合成

除了調用文字轉語音API外，Java還可以使用本地語音合成技術，也就是使用Java自帶的javax.speech包進行文字合成。該包是Java Speech API的一部分，旨在提供一種用於語音合成及識別的Java標準。下面是示例代碼：

import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.Clip;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.Mixer;
import javax.sound.sampled.Port;
import javax.sound.sampled.SourceDataLine;
import javax.sound.sampled.TargetDataLine;
import javax.sound.sampled.AudioFormat.Encoding;
import javax.speech.AudioException;
import javax.speech.Central;
import javax.speech.EngineList;
import javax.speech.EngineModeDesc;
import javax.speech.synthesis.SpeechEvent;
import javax.speech.synthesis.SpeechEventAdapter;
import javax.speech.synthesis.Synthesizer;
import javax.speech.synthesis.SynthesizerModeDesc;

public class TTS {

    private Synthesizer synthesizer;

    public void setText(String text) {
        try {
            // 獲取SynthesizerModeDesc描述類
            SynthesizerModeDesc desc = new SynthesizerModeDesc(null, "general", Locale.US, null, null);

            // 根據描述類創建Synthesizer對象
            synthesizer = Central.createSynthesizer(desc);

            // 打開Synthesizer
            synthesizer.allocate();
            synthesizer.resume();

            // 添加監聽器
            synthesizer.addEngineListener(new CustomSynthesizerListener());

            // 將文本輸入Synthesizer，並設置語音合成的音量、語速、音調等參數
            synthesizer.speak(text, null);
            synthesizer.waitEngineState(Synthesizer.QUEUE_EMPTY);

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (synthesizer != null)
                synthesizer.deallocate();
        }
    }

    /**
     * 監聽器
     */
    private class CustomSynthesizerListener extends SpeechEventAdapter {
        @Override
        public void processUnknown(SpeechEvent e) {
            System.out.println("喚醒：" + e.getSource() + " " + e.getId() + " " + e.getText());
        }
    }

    public static void main(String[] args) {
        TTS tts = new TTS();
        tts.setText("Java語音合成工具，方便易用，支持多種參數設置");
    }
}

四、Java實現語音轉文字

除了文字轉語音，Java也支持語音轉文字功能。相比文字轉語音，語音轉文字需要更多的演算法處理。目前市面上也有很多成熟的語音轉文字API，如訊飛開放平台、騰訊AI開放平台等。下面是使用訊飛開放平台API進行語音轉文字的示例代碼：

public class XunfeiDemo {
    private static final String URL = "http://api.xfyun.cn/v1/service/v1/iat";
    private static final String APP_ID = "your_app_id";
    private static final String API_KEY = "your_api_key";
    private static final String API_SECRET = "your_api_secret";

    // 音頻編碼
    private static final String AUE = "raw";

    // 結果格式
    private static final String RESULT_FORMAT = "json";

    public static void main(String[] args) throws Exception {
        File file = new File("test.pcm");
        FileInputStream fis = new FileInputStream(file);
        byte[] bytes = new byte[fis.available()];
        fis.read(bytes);
        fis.close();

        String audioBase64 = new BASE64Encoder().encode(bytes);

        String curTime = System.currentTimeMillis() / 1000L + "";
        String param = "{\"auf\":\"audio/L16;rate=16000\",\"aue\":\"" + AUE + "\",\"voice_name\":\"xiaoyan\",\"engine_type\":\"sms16k\",\"result_format\":\"" + RESULT_FORMAT + "\",\"grammar_list\":\"\",\"extend_params\":\"language=cn|accent=mun\",\"sub\":\"iat\",\"index\":0,\"language\":\"zh_cn\"}";
        String paramBase64 = new BASE64Encoder().encode(param.getBytes("UTF-8"));

        // 計算請求籤名
        String checkSum = DigestUtils.md5Hex(API_KEY + curTime + paramBase64).toLowerCase();

        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpPost httpPost = new HttpPost(URL);
        httpPost.setHeader("Content-Type", "application/x-www-form-urlencoded; charset=utf-8");
        httpPost.setHeader("X-CurTime", curTime);
        httpPost.setHeader("X-Param", paramBase64);
        httpPost.setHeader("X-Appid", APP_ID);
        httpPost.setHeader("X-CheckSum", checkSum);
        httpPost.setHeader("X-UserAgent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:84.0) Gecko/20100101 Firefox/84.0");
        StringEntity reqEntity = new StringEntity("audio=" + URLEncoder.encode(audioBase64, "UTF-8"), "UTF-8");
        httpPost.setEntity(reqEntity);

        CloseableHttpResponse httpResponse = httpClient.execute(httpPost);
        String result = EntityUtils.toString(httpResponse.getEntity(), "UTF-8");
        JSONObject jsonObject = JSONObject.parseObject(result);
        JSONArray jsonArray = jsonObject.getJSONObject("data").getJSONArray("result");
        StringBuilder stringBuilder = new StringBuilder();
        for (Object obj : jsonArray) {
            stringBuilder.append(obj.toString());
        }
        System.out.println(stringBuilder.toString());
    }
}