---
title: kVTEncodeFrameOptionKey_ForceKeyFrame
framework: videotoolbox
role: symbol
role_heading: Global Variable
path: videotoolbox/kvtencodeframeoptionkey_forcekeyframe
---

# kVTEncodeFrameOptionKey_ForceKeyFrame

Boolean value indicating whether the current frame is forced to be a key frame.

## Declaration

```swift
let kVTEncodeFrameOptionKey_ForceKeyFrame: CFString
```

## Discussion

Discussion This value is set in the frameProperties dictionary passed to VTCompressionSessionEncodeFrame(_:imageBuffer:presentationTimeStamp:duration:frameProperties:sourceFrameRefcon:infoFlagsOut:); it determines whether the current frame is forced to be a keyframe or not. Note that it may not be possible for the encoder to accommodate all requests.

## See Also

### Per-Frame Configuration

- [kVTEncodeFrameOptionKey_BaseFrameQP](videotoolbox/kvtencodeframeoptionkey_baseframeqp.md)