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# kVTCompressionPropertyKey_VBVInitialDelayPercentage

```
let kVTCompressionPropertyKey_VBVInitialDelayPercentage: CFString
```

## Discussion

\abstract Initial delay of the VBV model between storing the picture in the VBV buffer model and decoding of that picture, as a percentage of VBV buffer duration.
\discussion This value should be specified as a number in the range of 0 to 100.
Larger value increases the delay but results in smoother playback.
Default value is 90, meaning 90% of the VBV buffer duration.
This property key is incompatible with:

1. kVTCompressionPropertyKey_AverageBitRate,
2. kVTCompressionPropertyKey_DataRateLimits,
3. VTVideoEncoderSpecification_EnableLowLatencyRateControl=True.

---

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