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# SFVoiceAnalytics

A collection of vocal analysis metrics.

```
class SFVoiceAnalytics
```

## Overview

Use an [`SFAcousticFeature`](/documentation/Speech/SFAcousticFeature) object to access the `SFVoiceAnalytics` insights. Voice analytics include the following features:

- Use [`jitter`](/documentation/Speech/SFVoiceAnalytics/jitter) to measure how pitch varies in audio.
- Use [`shimmer`](/documentation/Speech/SFVoiceAnalytics/shimmer) to measure how amplitude varies in audio.
- Use [`pitch`](/documentation/Speech/SFVoiceAnalytics/pitch) to measure the highness and lowness of the tone.
- Use [`voicing`](/documentation/Speech/SFVoiceAnalytics/voicing) to identify voiced regions in speech.

These results are part of the [`SFTranscriptionSegment`](/documentation/Speech/SFTranscriptionSegment) object and are available when the system sends the [`isFinal`](/documentation/Speech/SFSpeechRecognitionResult/isFinal) flag.

## Topics

### Analyzing voice

[`SFAcousticFeature`](/documentation/Speech/SFAcousticFeature)

The value of a voice analysis metric.

[`voicing`](/documentation/Speech/SFVoiceAnalytics/voicing)

The likelihood of a voice in each frame of a transcription segment.

[`pitch`](/documentation/Speech/SFVoiceAnalytics/pitch)

The highness or lowness of the tone (fundamental frequency) in each frame of a transcription segment, expressed as a logarithm.

[`jitter`](/documentation/Speech/SFVoiceAnalytics/jitter)

The variation in pitch in each frame of a transcription segment, expressed as a percentage of the frame’s fundamental frequency.

[`shimmer`](/documentation/Speech/SFVoiceAnalytics/shimmer)

The variation in vocal volume stability (amplitude) in each frame of a transcription segment, expressed in decibels.


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