---
title: kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration
framework: videotoolbox
role: symbol
role_heading: Global Variable
path: videotoolbox/kvtcompressionpropertykey_maxkeyframeintervalduration
---

# kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration

The maximum duration from one key frame to the next in seconds.

## Declaration

```swift
let kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration: CFString
```

## Discussion

Discussion The default value is 0, which means no limit.  This property is particularly useful when the frame rate is variable. See kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration for more discussion of key frames. This key can be set in conjunction with kVTCompressionPropertyKey_MaxKeyFrameIntervalDuration, which requires a keyframe every X frames or every Y seconds, whichever comes first.

## See Also

### Frame Dependency

- [kVTCompressionPropertyKey_AllowFrameReordering](videotoolbox/kvtcompressionpropertykey_allowframereordering.md)
- [kVTCompressionPropertyKey_AllowOpenGOP](videotoolbox/kvtcompressionpropertykey_allowopengop.md)
- [kVTCompressionPropertyKey_AllowTemporalCompression](videotoolbox/kvtcompressionpropertykey_allowtemporalcompression.md)
- [kVTCompressionPropertyKey_MaxKeyFrameInterval](videotoolbox/kvtcompressionpropertykey_maxkeyframeinterval.md)