---
title: timeCodeFrameDuration
framework: avfoundation
role: symbol
role_heading: Type Property
path: avfoundation/avcaptionsettingskey/timecodeframeduration
---

# timeCodeFrameDuration

A key that identifies the frame duration that the system uses for the time code.

## Declaration

```swift
static let timeCodeFrameDuration: AVCaptionSettingsKey
```

## Discussion

Discussion Some formats, such as TTML, use time code notation to indicate the timing of a caption. Use this key to specify the frame rate of the time code.

## See Also

### Keys

- [mediaType](avfoundation/avcaptionsettingskey/mediatype.md)
- [mediaSubType](avfoundation/avcaptionsettingskey/mediasubtype.md)
- [useDropFrameTimeCode](avfoundation/avcaptionsettingskey/usedropframetimecode.md)