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# CIConvolution

The properties you use to configure a convolution filter.

```
protocol CIConvolution : CIFilterProtocol
```

## Topics

### Instance Properties

[`bias`](/documentation/CoreImage/CIConvolution/bias)

A value that’s added to each output pixel.

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

The image to use as an input image.

[`weights`](/documentation/CoreImage/CIConvolution/weights)

The convolution kernel.

## See Also

[`convolution3X3()`](/documentation/CoreImage/CIFilter-swift.class/convolution3X3())

Applies a convolution 3 x 3 filter to the `RGBA` components of an image.

[`convolution5X5()`](/documentation/CoreImage/CIFilter-swift.class/convolution5X5())

Applies a convolution 5 x 5 filter to the `RGBA` components image.

[`convolution7X7()`](/documentation/CoreImage/CIFilter-swift.class/convolution7X7())

Applies a convolution 7 x 7 filter to the `RGBA` color components of an image.

[`convolution9Horizontal()`](/documentation/CoreImage/CIFilter-swift.class/convolution9Horizontal())

Applies a convolution-9 horizontal filter to the `RGBA` components of an image.

[`convolution9Vertical()`](/documentation/CoreImage/CIFilter-swift.class/convolution9Vertical())

Applies a convolution-9 vertical filter to the `RGBA` components of an image.


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