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# SFTranscriptionSegment

A discrete part of an entire transcription, as identified by the speech recognizer.

```
class SFTranscriptionSegment
```

## Overview

Use [`SFTranscriptionSegment`](/documentation/Speech/SFTranscriptionSegment) to get details about a part of an overall [`SFTranscription`](/documentation/Speech/SFTranscription). An [`SFTranscriptionSegment`](/documentation/Speech/SFTranscriptionSegment) represents an utterance, which is a vocalized word or group of words that represent a single meaning to the speech recognizer ([`SFSpeechRecognizer`](/documentation/Speech/SFSpeechRecognizer)).

You don’t create transcription object segments directly. Instead, you access them from a transcription’s [`segments`](/documentation/Speech/SFTranscription/segments) property.

A transcription segment includes the following information:

- The text of the utterance, plus any alternative interpretations of the spoken word.
- The character range of the segment within the [`formattedString`](/documentation/Speech/SFTranscription/formattedString) of its parent [`SFTranscription`](/documentation/Speech/SFTranscription).
- A [`confidence`](/documentation/Speech/SFTranscriptionSegment/confidence) value, indicating how likely it is that the specified string matches the audible speech.
- A [`timestamp`](/documentation/Speech/SFTranscriptionSegment/timestamp) and [`duration`](/documentation/Speech/SFTranscriptionSegment/duration) value, indicating the position of the segment within the provided audio stream.

## Topics

### Transcribing the segment

[`substring`](/documentation/Speech/SFTranscriptionSegment/substring)

The string representation of the utterance in the transcription segment.

[`substringRange`](/documentation/Speech/SFTranscriptionSegment/substringRange)

The range information for the transcription segment’s substring, relative to the overall transcription.

[`alternativeSubstrings`](/documentation/Speech/SFTranscriptionSegment/alternativeSubstrings)

An array of alternate interpretations of the utterance in the transcription segment.

### Assessing the recognition confidence level

[`confidence`](/documentation/Speech/SFTranscriptionSegment/confidence)

The level of confidence the speech recognizer has in its recognition of the speech transcribed for the segment.

### Getting audio timing information

[`timestamp`](/documentation/Speech/SFTranscriptionSegment/timestamp)

The start time of the segment in the processed audio stream.

[`duration`](/documentation/Speech/SFTranscriptionSegment/duration)

The number of seconds it took for the user to speak the utterance represented by the segment.

### Deprecated

[`voiceAnalytics`](/documentation/Speech/SFTranscriptionSegment/voiceAnalytics)

An analysis of the transcription segment’s vocal properties.


---

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