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# kVTCompressionPropertyKey_SpatialAdaptiveQPLevel

A value that controls spatial adaptation of the quantization parameter (QP) based on per-frame statistics.

```
let kVTCompressionPropertyKey_SpatialAdaptiveQPLevel: CFString
```

## Discussion

If set to [`kVTQPModulationLevel_Disable`](/documentation/VideoToolbox/kVTQPModulationLevel_Disable), spatial QP adaptation is not applied based on per-frame statistics.
If set to [`kVTQPModulationLevel_Default`](/documentation/VideoToolbox/kVTQPModulationLevel_Default), video encoder is allowed to apply spatial QP adaptation for each macro block (or coding unit) within a video frame.
QP adaptation is based on spatial characteristics of a frame and the level of spatial QP adaptation is decided internally by the rate controller.

## Topics

### Levels

[`kVTQPModulationLevel_Default`](/documentation/VideoToolbox/kVTQPModulationLevel_Default)

[`kVTQPModulationLevel_Disable`](/documentation/VideoToolbox/kVTQPModulationLevel_Disable)


---

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