Licensed under CC0 (https://creativecommons.org/publicdomain/zero/1.0/deed)

twitch-speakout-voiceroid.js

const API_KEY = 'ここにAPIキーを貼る';
const url = `https://api.apigw.smt.docomo.ne.jp/aiTalk/v1/textToSpeech?APIKEY=${API_KEY}`;

document.addEventListener('onEventReceived', async function(obj) {
    if (obj.detail.command == 'PRIVMSG') {
        play(obj.detail.body, 'maki');
    }
});

async function play(text, who) {
    const result = await fetch(new URL(url), {
        method: 'POST',
        body: `<?xml version="1.0" encoding="utf-8" ?>
        <speak version="1.1"><voice name="${who}">${text}</voice></speak>`,
        headers: new Headers({
            'Content-Type': 'application/ssml+xml;charset=UTF-8',
            'Accept': 'audio/L16',
        })
    });
    const audioRawBuffer = await result.arrayBuffer();
    const audioDataView = new DataView(audioRawBuffer);
    
    const audioContext = new AudioContext();
    const audioBuffer = audioContext.createBuffer(1, audioDataView.byteLength / 2, 16000);
    const channel = audioBuffer.getChannelData(0);

    for (let i = 0; i < audioDataView.byteLength; i += 2) {
        const value = audioDataView.getInt16(i, false);
        channel[i / 2] = value / 32768.0;
    }

    const source = audioContext.createBufferSource();
    source.buffer = audioBuffer;
    source.connect(audioContext.destination);
    source.start();
}