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# CILineOverlay

The properties you use to configure a line overlay filter.

```
protocol CILineOverlay : CIFilterProtocol
```

## Topics

### Instance Properties

[`nrNoiseLevel`](/documentation/CoreImage/CILineOverlay/nrNoiseLevel)

The noise level of the image, used with camera data, that’s removed before tracing the edges of the image.

[`nrSharpness`](/documentation/CoreImage/CILineOverlay/nrSharpness)

The amount of sharpening done when removing noise in the image before tracing the edges of the image.

[`contrast`](/documentation/CoreImage/CILineOverlay/contrast)

The amount of antialiasing to use on the edges produced by this filter.

[`edgeIntensity`](/documentation/CoreImage/CILineOverlay/edgeIntensity)

The accentuation factor of the Sobel gradient information when tracing the edges of the image.

[`inputImage`](/documentation/CoreImage/CILineOverlay/inputImage)

The image to use as an input image.

[`threshold`](/documentation/CoreImage/CILineOverlay/threshold)

A value that determines edge visibility.

## See Also

[`lineOverlay()`](/documentation/CoreImage/CIFilter-swift.class/lineOverlay())

Creates an image that resembles a sketch of the outlines of objects.


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