Media

Manages YouTube-based audio playback via the IFrame Player API. The service contains a SvYouTubeAudioPlayer subnode that wraps a hidden YouTube player element.

SvYouTubeAudioPlayer

The core playback class. Handles player lifecycle, volume, looping, and state tracking. The YouTube IFrame API script is loaded lazily on first use, and playback waits for a user gesture (browser autoplay policy).

// Create a player and loop background music
const player = SvYouTubeAudioPlayer.clone();
player.setTrackName("Ambient Forest");
player.setVideoId("abc123xyz");
player.setShouldRepeat(true);
player.setVolume(0.1);
player.play();

// Control
player.stop();
player.togglePlay();
player.isPlaying();       // => boolean
player.stateName();       // => "playing" | "paused" | "buffering" | "ended"

// One-shot playback (resolves when video ends)
player.setShouldRepeat(false);
await player.play();

// Cleanup
await player.shutdown();  // destroys the YT.Player and removes the DOM element

SvMusicLibrary

A higher-level layer that manages playlists of SvMusicTrack nodes loaded from a JSON resource file. Owns two SvYouTubeAudioPlayer instances — one for background music (low volume), one for sound effects (higher volume).

// Play looping background music by track name
library.playTrackWithName("Mystical Forest");

// Play a one-shot sound effect
await library.playSoundEffectWithName("Sword Clash");

// Stop background music
library.musicPlayer().stop();

// Lookup
library.trackWithName("Battle Theme");       // => SvMusicTrack
library.playlists();                          // => SvMusicFolder[]
library.trackNames();                         // => String[]

Playlist data is a JSON object mapping folder names to track dictionaries:

{
  "Fantasy": {
    "Mystical Forest": "YouTubeVideoId1",
    "Battle Theme": "YouTubeVideoId2"
  },
  "Sound FX": {
    "Sword Clash": "YouTubeVideoId3"
  }
}

SvMusicTrack

Represents a single track with a YouTube video ID. Supports a delegate set for playback notifications:

track.addDelegate(myObserver);
await track.play();
track.stop();

Delegates receive onSoundStarted(track) and onSoundEnded(track).

Wraps the browser's native SpeechRecognition API for voice input. Each SvSpeechToTextSession tracks recognition state, language settings, and transcription results. Not a cloud service — all processing happens in the browser.

SvSpeechToTextSession

const session = SvSpeechToTextSession.clone();
session.setDelegate(myObject);
session.setLanguage("en-US");
session.setIsContinuous(true);
session.setGetInterimResults(true);
session.setInputTimeoutMs(1500);

// Start — returns a promise that resolves with the transcript
// when the input timeout fires (silence detected after speech)
const text = await session.start();

// Manual stop
session.stop();

// State
session.isRecording();
session.fullTranscript();       // accumulated text
session.interimTranscript();    // current partial text

Delegate Protocol

All methods are optional. The session is passed as the first argument.

Usage in SvTextView

Any text field supports voice input via Alt+L. Holding the key starts a session; releasing it stops recognition and inserts the transcript at the cursor:

startSpeechToText () {
    this._speechSession = SvSpeechToTextSession.clone().setDelegate(this);
    this._speechSession.start();
}

onSpeechEnd (speechSession) {
    const s = speechSession.fullTranscript();
    this.insertTextAtCursorSimple(s);
    this._speechSession = null;
}