---
title: AVVideoCompressionPropertiesKey
framework: avfoundation
role: symbol
role_heading: Global Variable
path: avfoundation/avvideocompressionpropertieskey
---

# AVVideoCompressionPropertiesKey

A key to access the dictionary of compression properties for a video asset.

## Declaration

```swift
let AVVideoCompressionPropertiesKey: String
```

## Discussion

Discussion The value for this key is an instance of NSDictionary. Add entries to this dictionary to manually change bit rate, B-frame delivery, I-frame interval, and codec quality. Querying the supportedOutputSettingsKeys(for:) method reveals the keys supported for the current release and configuration.

## See Also

### Compression

- [AVVideoDecompressionPropertiesKey](avfoundation/avvideodecompressionpropertieskey.md)
- [AVVideoAverageBitRateKey](avfoundation/avvideoaveragebitratekey.md)
- [AVVideoQualityKey](avfoundation/avvideoqualitykey.md)
- [AVVideoMaxKeyFrameIntervalKey](avfoundation/avvideomaxkeyframeintervalkey.md)
- [AVVideoMaxKeyFrameIntervalDurationKey](avfoundation/avvideomaxkeyframeintervaldurationkey.md)
- [AVVideoAllowFrameReorderingKey](avfoundation/avvideoallowframereorderingkey.md)
- [AVVideoAppleProRAWBitDepthKey](avfoundation/avvideoappleprorawbitdepthkey.md)