chore(voice): remove amplitude-based silence detector (replaced by VAD)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This commit is contained in:
2026-04-16 17:47:45 -04:00
parent 0a8a755909
commit a4995606e5
@@ -1,121 +0,0 @@
import { ref, readonly } from 'vue'
export interface SilenceDetectorOptions {
/**
* Absolute fallback silence threshold in dBFS, used during the first
* moments before any real speech has been observed. Once the session peak
* clears `dynamicArmDb` we switch to the dynamic threshold instead.
*/
fallbackThresholdDb?: number // default -45
/** How many dB below the session peak counts as "silent" once armed. */
dropFromPeakDb?: number // default 15
/**
* Session peak must reach this level (dBFS) before dynamic thresholding
* kicks in. Until then the fallback threshold is used so we don't lock
* onto a noise-floor peak.
*/
dynamicArmDb?: number // default -25
/** How long to wait at the start of recording before running silence checks. */
graceMs?: number // default 1500
silenceDurationMs?: number // default 2000
minRecordingMs?: number // default 500
}
/**
* Mic silence detector + live amplitude signal.
*
* Uses `getFloatTimeDomainData()` for honest linear RMS in [-1, 1] space,
* then derives dBFS for the silence threshold. The previous implementation
* ran RMS over `getByteFrequencyData` bytes — those bytes are already a
* dB-scaled quantity, so taking their RMS and re-log'ing it produced
* numbers that didn't line up with real dBFS and made any static threshold
* unpredictable.
*
* Silence threshold is dynamic: we track the session peak dBFS and treat
* "silent" as "current level is at least [dropFromPeakDb] below peak."
* This auto-calibrates to whatever mic and room the user is on. Until the
* peak climbs above [dynamicArmDb] we fall back to a conservative static
* threshold so a quiet room doesn't spin forever. A grace period at the
* start of the recording gives the user time to begin speaking before
* silence checks arm.
*
* `amplitude` is the raw linear RMS scaled ×5 and clamped to 1 so quiet
* speech still visibly moves UI that binds to it.
*/
export function useSilenceDetector(options: SilenceDetectorOptions = {}) {
const {
fallbackThresholdDb = -45,
dropFromPeakDb = 15,
dynamicArmDb = -25,
graceMs = 1500,
silenceDurationMs = 2000,
minRecordingMs = 500,
} = options
const amplitude = ref(0)
let audioCtx: AudioContext | null = null
let intervalId: ReturnType<typeof setInterval> | null = null
let silenceMs = 0
let startedAt = 0
let peakDb = -100
function start(stream: MediaStream, onSilence: () => void): void {
stop()
audioCtx = new AudioContext()
// Some browsers start AudioContext in "suspended" state — resume so
// the analyser returns real values instead of all zeros.
audioCtx.resume().catch(() => {})
const source = audioCtx.createMediaStreamSource(stream)
const analyser = audioCtx.createAnalyser()
analyser.fftSize = 1024
source.connect(analyser)
const samples = new Float32Array(analyser.fftSize)
silenceMs = 0
startedAt = Date.now()
peakDb = -100
intervalId = setInterval(() => {
analyser.getFloatTimeDomainData(samples)
let sumSq = 0
for (let i = 0; i < samples.length; i++) sumSq += samples[i] * samples[i]
const rms = Math.sqrt(sumSq / samples.length)
amplitude.value = Math.min(rms * 5, 1)
const db = rms > 1e-7 ? 20 * Math.log10(rms) : -100
if (db > peakDb) peakDb = db
const elapsed = Date.now() - startedAt
if (elapsed < graceMs) return
const threshold =
peakDb > dynamicArmDb ? peakDb - dropFromPeakDb : fallbackThresholdDb
if (db < threshold) {
silenceMs += 100
if (silenceMs >= silenceDurationMs && elapsed >= minRecordingMs) {
stop()
onSilence()
}
} else {
silenceMs = 0
}
}, 100)
}
function stop(): void {
if (intervalId !== null) {
clearInterval(intervalId)
intervalId = null
}
if (audioCtx) {
audioCtx.close().catch(() => {})
audioCtx = null
}
amplitude.value = 0
silenceMs = 0
peakDb = -100
}
return { amplitude: readonly(amplitude), start, stop }
}