---
title: kIOVideoFeatureControlClassIDGamma
framework: Kernel
role: symbol
role_heading: Enumeration Case
platforms: [macOS 10.12+]
path: kernel/1646200-anonymous/kiovideofeaturecontrolclassidgamma
---

# kIOVideoFeatureControlClassIDGamma

## Declaration

```occ
kIOVideoFeatureControlClassIDGamma = 'gmma'
```

## Discussion

Discussion A IOVideoFeatureControl that defines the function between incoming light level and output picture level. The units for the control's absolute value are undefined.