---
title: initialSegmentStartTime
framework: avfoundation
role: symbol
role_heading: Instance Property
path: avfoundation/avassetwriter/initialsegmentstarttime
---

# initialSegmentStartTime

The start time of the initial segment.

## Declaration

```swift
var initialSegmentStartTime: CMTime { get set }
```

## Discussion

Discussion This value is relevant only when the preferredOutputSegmentInterval property value is positive numeric, in which case you must set a numeric time. You can’t change this value after writing starts.

## See Also

### Configuring segment writing

- [delegate](avfoundation/avassetwriter/delegate.md)
- [AVAssetWriterDelegate](avfoundation/avassetwriterdelegate.md)
- [preferredOutputSegmentInterval](avfoundation/avassetwriter/preferredoutputsegmentinterval.md)
- [outputFileTypeProfile](avfoundation/avassetwriter/outputfiletypeprofile.md)
- [flushSegment()](avfoundation/avassetwriter/flushsegment().md)