Class: StatsSampler

Turns successive RTCStatsReports into samples.

Stateful because the interesting numbers are rates and the report carries counters: bitrate is bytes since the last sample, loss is lost-since-last over received-since-last. Taking loss from the cumulative counters instead — which is the obvious reading of the report — averages a call's whole history and reports "fine" for minutes after the line has gone bad.

Every field of a sample is the interval since the last one, the NACK, PLI and freeze counts included. Those three were sent as the report's running totals until 2026-09-29, beside rates that were not: a row every five seconds each repeating the call's whole history, so a column summed over a call counted its first NACK once per sample.

Constructors

Constructor

new StatsSampler(): StatsSampler;

Returns

StatsSampler

Methods

reset()

reset(): void;

Returns

void

---

sample()

sample(
   report, 
   atMs, 
   opts?
): StatsSample[];

opts.skip drops a stream that is not a track — the sfu subscriber's probator — and opts.trackSidOf names the TR_ sid a stream carries, where there is one (an sfu room; never p2p).

opts.interrupted says whether the connection a stream arrives on is disconnected or failed. A stream that received nothing there lost everything it was sent: its loss is 100 %, not the 0-of-0 the counters give, which graded a frozen call excellent (measured). On a connection that is up, the same silence is a paused or muted track.

Parameters

Parameter	Type
report	RTCStatsReport
atMs	number
opts	{ interrupted?: (stat) => boolean; skip?: (stat) => boolean; trackSidOf?: (stat) => string; }
opts.interrupted?	(stat) => boolean
opts.skip?	(stat) => boolean
opts.trackSidOf?	(stat) => string

Returns

StatsSample[]