Struct ArrivalOrderSpeakerCache 

pub struct ArrivalOrderSpeakerCache { /* private fields */ }

Bounded arrival-order speaker cache for online diarization.

Overflow / merge semantics

When len() == cap and an embedding does not match any entry above match_threshold, it is force-merged into the closest entry (no new speaker is created). This mirrors AWS Transcribe’s documented overflow behaviour and keeps per-chunk work O(cap).

Eviction (dropping the lowest keep-score entry) is available via Self::evict_weakest for long streams that need to free a slot for a clearly new speaker; the default assign path uses force-merge only so arrival-order IDs never renumber mid-stream.

Implementations

impl ArrivalOrderSpeakerCache

pub fn new( cap: usize, match_threshold: f32, min_hits_to_stable: usize, prefer_current_margin: f32, ) -> Self

Create an empty cache.

cap is clamped to at least 1 — a zero-capacity cache could never hold a speaker, so it is treated as a request for the smallest usable cache (same policy as the min_hits_to_stable clamp below).

pub fn len(&self) -> usize

Number of speakers currently in the cache (<= cap).

pub fn is_empty(&self) -> bool

true when the cache holds no speakers.

pub fn cap(&self) -> usize

Configured maximum size.

pub fn speaker_ids(&self) -> Vec<SpeakerId>

Arrival-order speaker IDs currently resident (sorted by id).

pub fn assign(&mut self, embedding: &[f32]) -> AssignResult

Assign an embedding to a speaker via cache match / create / overflow merge.

pub fn evict_weakest(&mut self) -> Option<SpeakerId>

Drop the lowest keep-score entry if the cache is at capacity. Returns the evicted speaker id, if any.