---
title: kVTCompressionPropertyKey_ConstantBitRate
framework: videotoolbox
role: symbol
role_heading: Global Variable
path: videotoolbox/kvtcompressionpropertykey_constantbitrate
---

# kVTCompressionPropertyKey_ConstantBitRate

Requires that the encoder use a Constant Bit Rate algorithm.

## Declaration

```swift
let kVTCompressionPropertyKey_ConstantBitRate: CFString
```

## See Also

### Rate Control

- [kVTCompressionPropertyKey_AverageBitRate](videotoolbox/kvtcompressionpropertykey_averagebitrate.md)
- [kVTCompressionPropertyKey_DataRateLimits](videotoolbox/kvtcompressionpropertykey_dataratelimits.md)
- [kVTCompressionPropertyKey_EstimatedAverageBytesPerFrame](videotoolbox/kvtcompressionpropertykey_estimatedaveragebytesperframe.md)
- [kVTCompressionPropertyKey_MoreFramesAfterEnd](videotoolbox/kvtcompressionpropertykey_moreframesafterend.md)
- [kVTCompressionPropertyKey_MoreFramesBeforeStart](videotoolbox/kvtcompressionpropertykey_moreframesbeforestart.md)
- [kVTCompressionPropertyKey_Quality](videotoolbox/kvtcompressionpropertykey_quality.md)
- [kVTCompressionPropertyKey_TargetQualityForAlpha](videotoolbox/kvtcompressionpropertykey_targetqualityforalpha.md)
- [kVTCompressionPropertyKey_VariableBitRate](videotoolbox/kvtcompressionpropertykey_variablebitrate.md)
- [kVTCompressionPropertyKey_VBVBufferDuration](videotoolbox/kvtcompressionpropertykey_vbvbufferduration.md)
- [kVTCompressionPropertyKey_VBVInitialDelayPercentage](videotoolbox/kvtcompressionpropertykey_vbvinitialdelaypercentage.md)
- [kVTCompressionPropertyKey_VBVMaxBitRate](videotoolbox/kvtcompressionpropertykey_vbvmaxbitrate.md)