---
title: mask
framework: coreimage
role: symbol
role_heading: Instance Property
path: coreimage/cimaskedvariableblur/mask
---

# mask

A grayscale mask that defines the blur amount.

## Declaration

```swift
var mask: CIImage? { get set }
```

## See Also

### Instance Properties

- [inputImage](coreimage/cimaskedvariableblur/inputimage.md)
- [radius](coreimage/cimaskedvariableblur/radius.md)