<!--
{
  "availability" : [
    "iOS: 17.0.0 -",
    "iPadOS: 17.0.0 -",
    "macCatalyst: 17.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "SensorKit",
  "identifier" : "/documentation/SensorKit/SRSpeechExpression",
  "metadataVersion" : "0.1.0",
  "role" : "Class",
  "symbol" : {
    "kind" : "Class",
    "modules" : [
      "SensorKit"
    ],
    "preciseIdentifier" : "c:objc(cs)SRSpeechExpression"
  },
  "title" : "SRSpeechExpression"
}
-->

# SRSpeechExpression

An object that represents the metrics and voice analytics for a range of speech.

```
class SRSpeechExpression
```

## Overview

Use the properties of this class to get the characteristics of the speech, such as the user’s confidence level and mood.

## Topics

### Getting speech metrics

[`var timeRange: CMTimeRange`](/documentation/SensorKit/SRSpeechExpression/timeRange)

The time range in the audio stream that the metrics and analytics apply to.

[`var version: String`](/documentation/SensorKit/SRSpeechExpression/version)

The version of the algorithm that the system uses to generate the metrics and analytics.

### Getting speech analytics

[`var confidence: Double`](/documentation/SensorKit/SRSpeechExpression/confidence)

The level of confidence of the speaker.

[`var mood: Double`](/documentation/SensorKit/SRSpeechExpression/mood)

An indication of how slurry, tired, or exhausted the speaker sounds compared to normal speech.

[`var valence: Double`](/documentation/SensorKit/SRSpeechExpression/valence)

The degree of positive or negative emotion or sentiment of the speaker.

[`var activation: Double`](/documentation/SensorKit/SRSpeechExpression/activation)

The level of energy or activation of the speaker.

[`var dominance: Double`](/documentation/SensorKit/SRSpeechExpression/dominance)

The degree of how strong or meek the speaker sounds.

## Relationships

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

### Conforms To

[`NSCoding`](/documentation/Foundation/NSCoding)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CVarArg`](/documentation/Swift/CVarArg)

[`Sendable`](/documentation/Swift/Sendable)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`Equatable`](/documentation/Swift/Equatable)

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)