Rendley SDK

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Audio Clip ​

The AudioClip plays an audio file on the timeline. It supports trimming, playback speed, pitch preservation, and volume fades.

Create an Audio Clip ​

The duration is inferred from the media data.

typescript
const mediaId = await Engine.getInstance()
  .getLibrary()
  .addMedia("https://example.com/voiceover.mp3");

await layer.addClip({
  mediaDataId: mediaId,
  startTime: 0,
});
List of Supported Formats
FormatSupport
MP3✅
M4A✅
OGG✅
WAV✅
AAC✅

Volume and Mute ​

typescript
audioClip.setVolume(0.5);
audioClip.setMuted(true);

Adding Background Music ​

Background music is just an audio clip on its own layer, trimmed to the composition length and faded in / out so it doesn't start or end abruptly. A typical setup:

typescript
const musicMediaId = await Engine.getInstance()
  .getLibrary()
  .addMedia("https://example.com/song.mp3");

const musicLayer = Engine.getInstance().getTimeline().createLayer();
const music = await musicLayer.addClip({
  mediaDataId: musicMediaId,
  startTime: 0,
});

// Trim the music to the composition length.
const duration = Engine.getInstance().getTimeline().getFitDuration();
music.setRightTrim(Math.max(0, music.getDuration() - duration));

// Keep the music quieter than dialogue.
music.setVolume(0.3);

// Smooth fade-in and fade-out at the boundaries.
music.setVolumeFadeInDuration(1.0);
music.setVolumeFadeOutDuration(2.0);

If the music is longer than the composition, setRightTrim cuts the tail. If it's shorter, duplicate the clip on the same layer to extend playback, or use a single long track.

Playback Speed and Fades ​

Speed, pitch, and fade in/out are covered on the Playback Speed & Fades page.

Waveform Samples ​

If you enable clipAudioStoreSamples in the Settings before adding the media, the SDK extracts normalized Float32Array samples you can use to draw a waveform or drive custom clips.

typescript
const samples = audioClip.getAudioSamples(0); // start at 0, full duration

See Filmstrip & Waveforms for the full workflow.

See Also ​