[AdirAmsalem]

Summary

realtime.subscribe() can now also receive the session's input: the tracks its publisher sends into the room (camera, microphone), e.g. to show the original next to the styled output.

await client.realtime.subscribe({
  token,
  onRemoteStream: (stream) => (outputVideo.srcObject = stream),
  onInputStream: (stream) => (inputVideo.srcObject = stream),
  inputVideoQuality: "low", // "low" | "medium" | "high" (default)
});

Changes

• SubscribeOptions.onInputStream?: (stream: MediaStream) => void: a fresh MediaStream whenever the input's track set changes, same contract as onRemoteStream.
• SubscribeOptions.inputVideoQuality?: "low" | "medium" | "high" (new exported type SubscribeVideoQuality), default "high": the highest simulcast layer of the input video to receive; the SFU still steps down under bandwidth pressure.
• subscribe() now joins with autoSubscribe: false and subscribes per track, mirroring connect()'s media channel: the inference server's tracks always, any other participant's tracks only when onInputStream is set. Publications present at join are swept after connect, and again on Reconnected.
  • Side effect for existing subscribers: they no longer download the publisher's camera/mic only to drop them in the TrackSubscribed filter.
• livekit-client's VideoQuality is only read when onInputStream is set, so existing callers don't depend on it.
• README: viewer-with-input example.

Tests

pnpm test: 391 passed (387 before + 4 new): subscribe joins without auto-subscribe and never subscribes to the input unless asked (including late publications); input tracks reach onInputStream (fresh stream per change, output unaffected) at HIGH by default; inputVideoQuality: "low" requests LOW; output and input are re-subscribed after a full reconnect. Typecheck, Biome, build and test:package pass.

---

Note

Medium Risk
Changes LiveKit subscription behavior for all subscribers (autoSubscribe off) and adds optional publisher media download; well-tested but affects core realtime viewing paths.

Overview
realtime.subscribe() can optionally receive the publisher’s camera/mic alongside the styled output via onInputStream and inputVideoQuality (low | medium | high, default high), exported as SubscribeVideoQuality.

Subscribe now joins LiveKit with autoSubscribe: false and subscribes per publication: inference-server output always; publisher input only when onInputStream is set, with simulcast quality on input video. Existing viewers that only use onRemoteStream stop downloading publisher tracks they previously ignored. Track handling uses a shared withTrack helper (fresh MediaStream per change, ended tracks dropped); subscriptions are re-applied after connect and on Reconnected. README documents a side-by-side viewer example; unit tests cover the new behavior.

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[decartdev]

Approved at the author's request. CI green.