> ## 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.

# Segmentation Config

> Tune VAD segmentation for your use case.

## VadSegmentationConfig

```swift theme={null}
public struct VadSegmentationConfig {
    var minSpeechDuration: TimeInterval    // Default: 0.15s
    var minSilenceDuration: TimeInterval   // Default: 0.75s
    var maxSpeechDuration: TimeInterval    // Default: 14s
    var speechPadding: TimeInterval        // Default: 0.1s
    var silenceThresholdForSplit: Float    // Default: 0.3
    var negativeThreshold: Float?          // Default: nil (auto)
    var negativeThresholdOffset: Float     // Default: 0.15
    var minSilenceAtMaxSpeech: TimeInterval // Default: 0.098s
    var useMaxPossibleSilenceAtMaxSpeech: Bool // Default: true
}
```

## Parameters

| Parameter                          | Default | Description                                                                                            |
| ---------------------------------- | ------- | ------------------------------------------------------------------------------------------------------ |
| `minSpeechDuration`                | 0.15s   | Minimum speech to keep. Prevents clicks/coughs from being treated as speech.                           |
| `minSilenceDuration`               | 0.75s   | Silence required to end a segment. Prevents early cut-offs during brief pauses.                        |
| `maxSpeechDuration`                | 14s     | Force-split long segments to match ASR model limits.                                                   |
| `speechPadding`                    | 0.1s    | Context padding on both sides of each segment.                                                         |
| `silenceThresholdForSplit`         | 0.3     | Probability below which audio is treated as silence for splitting.                                     |
| `negativeThreshold`                | nil     | Override for exit hysteresis threshold. If nil, computed as `baseThreshold - negativeThresholdOffset`. |
| `negativeThresholdOffset`          | 0.15    | Gap between entry and exit thresholds. Creates a "sticky zone" to prevent rapid flipping.              |
| `minSilenceAtMaxSpeech`            | 0.098s  | Minimum silence at forced split points. Ensures splits don't land mid-phoneme.                         |
| `useMaxPossibleSilenceAtMaxSpeech` | true    | Split at the longest silence near max duration for cleaner boundaries.                                 |

## Hysteresis

The entry/exit threshold system prevents rapid state toggling:

* **Enter speech** when probability > `baseThreshold`
* **Exit speech** when probability \< `negativeThreshold`
* **Stay in current state** when probability is between the two

The entry threshold defaults to `VadConfig.defaultThreshold` set when constructing `VadManager`.