Documentation Index
Fetch the complete documentation index at: https://docs.fluidinference.com/llms.txt
Use this file to discover all available pages before exploring further.
When to Use
- Pre-process audio before ASR — Segment files into speech regions, skip silence. Reduces ASR processing by 30-50%.
- Real-time speech detection — Trigger recording or UI when user starts/stops speaking.
- Improve diarization quality — Filter noise before speaker embedding extraction. Reduces false speakers by 20-40%.
Specs
| Metric | Value |
|---|
| Model | Silero VAD v6 |
| Window size | 256ms |
| Memory | Minimal (runs on CPU) |
Offline Segmentation
import FluidAudio
let manager = try await VadManager(
config: VadConfig(defaultThreshold: 0.75)
)
let samples = try AudioConverter().resampleAudioFile(
URL(fileURLWithPath: "audio.wav")
)
var segmentation = VadSegmentationConfig.default
segmentation.minSpeechDuration = 0.25
segmentation.minSilenceDuration = 0.4
segmentation.speechPadding = 0.12
let segments = try await manager.segmentSpeech(samples, config: segmentation)
for (index, segment) in segments.enumerated() {
print(String(format: "Segment %02d: %.2f-%.2fs", index + 1, segment.startTime, segment.endTime))
}
Get Audio Clips
let clips = try await manager.segmentSpeechAudio(samples, config: segmentation)
print("Extracted \(clips.count) buffered segments ready for ASR")
Chunk-Level Probabilities
let results = try await manager.process(samples)
for (index, chunk) in results.enumerated() {
print(String(format: "Chunk %02d: prob=%.3f", index, chunk.probability))
}
Manual Model Loading
Stage the Core ML bundle for offline environments:
let modelURL = URL(
fileURLWithPath: "/opt/models/silero-vad-coreml/silero-vad-unified-256ms-v6.0.0.mlmodelc",
isDirectory: true
)
var configuration = MLModelConfiguration()
configuration.computeUnits = .cpuOnly
let vadModel = try MLModel(contentsOf: modelURL, configuration: configuration)
let manager = VadManager(config: .default, vadModel: vadModel)
Benchmarks
VOiCES (25 files, clean speech):
| Metric | Value |
|---|
| Accuracy | 96.0% |
| Precision | 100.0% |
| Recall | 95.8% |
| F1-Score | 97.9% |
| RTFx | 1,230x |
| Metric | Value |
|---|
| Accuracy | 94.2% |
| Precision | 92.6% |
| Recall | 78.9% |
| F1-Score | 85.2% |
| RTFx | 1,221x |
CLI
# Offline segmentation
swift run fluidaudio vad-analyze audio.wav
# Streaming mode
swift run fluidaudio vad-analyze audio.wav --streaming --min-silence-ms 300
# Both modes
swift run fluidaudio vad-analyze audio.wav --mode both
# Benchmark
swift run fluidaudio vad-benchmark --num-files 50 --threshold 0.3
