# Filter Parameter Keys Keys for input parameters to filters. ## Discussion These keys represent some of the most commonly used input parameters. A filter can use other kinds of input parameters. ## Topics ### Constants [`kCIDynamicRangeConstrainedHigh`](/documentation/CoreImage/CIDynamicRangeOption/constrainedHigh) Use extended dynamic range, but brightness is modulated to optimize for co-existence with other composited content. [`kCIDynamicRangeHigh`](/documentation/CoreImage/CIDynamicRangeOption/high) Use High dynamic range. [`kCIDynamicRangeStandard`](/documentation/CoreImage/CIDynamicRangeOption/standard) Use Standard dynamic range. [`kCIInputAmountKey`](/documentation/CoreImage/kCIInputAmountKey) [`kCIInputAngleKey`](/documentation/CoreImage/kCIInputAngleKey) The angle. [`kCIInputAspectRatioKey`](/documentation/CoreImage/kCIInputAspectRatioKey) Aspect Ratio. [`kCIInputBackgroundImageKey`](/documentation/CoreImage/kCIInputBackgroundImageKey) A key for the [`CIImage`](/documentation/CoreImage/CIImage) object to use as a background image. [`kCIInputBacksideImageKey`](/documentation/CoreImage/kCIInputBacksideImageKey) A key to get or set the backside image for a transition Core Image filter. [`kCIInputBiasVectorKey`](/documentation/CoreImage/kCIInputBiasVectorKey) A key to get or set the vector bias value of a Core Image filter. [`kCIInputBrightnessKey`](/documentation/CoreImage/kCIInputBrightnessKey) Brightness level. [`kCIInputCenterKey`](/documentation/CoreImage/kCIInputCenterKey) A key for a [`CIVector`](/documentation/CoreImage/CIVector) object that specifies the center of the area, as *x* and *y*- coordinates, to be filtered. [`kCIInputColorKey`](/documentation/CoreImage/kCIInputColorKey) A key for a [`CIColor`](/documentation/CoreImage/CIColor) object that specifies a color value. [`kCIInputColor0Key`](/documentation/CoreImage/kCIInputColor0Key) A key to get or set a color value of a Core Image filter. [`kCIInputColor1Key`](/documentation/CoreImage/kCIInputColor1Key) A key to get or set a color value of a Core Image filter. [`kCIInputColorSpaceKey`](/documentation/CoreImage/kCIInputColorSpaceKey) A key to get or set a color space value of a Core Image filter. [`kCIInputContrastKey`](/documentation/CoreImage/kCIInputContrastKey) A contrast level. [`kCIInputCountKey`](/documentation/CoreImage/kCIInputCountKey) A key to get or set the scalar count value of a Core Image filter. [`kCIInputDepthImageKey`](/documentation/CoreImage/kCIInputDepthImageKey) A key for an image with depth values. [`kCIInputDisparityImageKey`](/documentation/CoreImage/kCIInputDisparityImageKey) A key for an image with disparity values. [`kCIInputEVKey`](/documentation/CoreImage/kCIInputEVKey) How many F-stops brighter or darker the image should be. [`kCIInputExtentKey`](/documentation/CoreImage/kCIInputExtentKey) A key for a [`CIVector`](/documentation/CoreImage/CIVector) object that specifies a rectangle that defines the extent of the effect. [`kCIInputExtrapolateKey`](/documentation/CoreImage/kCIInputExtrapolateKey) A key to get or set the boolean behavior of a Core Image filter that specifies if the filter should extrapolate a table beyond the defined range. [`kCIInputGradientImageKey`](/documentation/CoreImage/kCIInputGradientImageKey) A key for a [`CIImage`](/documentation/CoreImage/CIImage) object that specifies an environment map with alpha. Typically, this image contains highlight and shadow. [`kCIInputImageKey`](/documentation/CoreImage/kCIInputImageKey) A key for the [`CIImage`](/documentation/CoreImage/CIImage) object to use as an input image. For filters that also use a background image, this key refers to the foreground image. [`kCIInputIntensityKey`](/documentation/CoreImage/kCIInputIntensityKey) An intensity value. [`kCIInputMaskImageKey`](/documentation/CoreImage/kCIInputMaskImageKey) A key for a [`CIImage`](/documentation/CoreImage/CIImage) object to use as a mask. [`kCIInputMatteImageKey`](/documentation/CoreImage/kCIInputMatteImageKey) [`kCIInputPaletteImageKey`](/documentation/CoreImage/kCIInputPaletteImageKey) A key to get or set the palette image for a Core Image filter. [`kCIInputPerceptualKey`](/documentation/CoreImage/kCIInputPerceptualKey) A key to get or set the boolean behavior of a Core Image filter that specifies if the filter should operate in linear or perceptual colors. [`kCIInputPoint0Key`](/documentation/CoreImage/kCIInputPoint0Key) A key to get or set the coordinate value of a Core Image filter. The value for this key needs to be a [`CIVector`](/documentation/CoreImage/CIVector) instance containing the `x,y` coordinate. [`kCIInputPoint1Key`](/documentation/CoreImage/kCIInputPoint1Key) A key to get or set a coordinate value of a Core Image filter. The value for this key needs to be a [`CIVector`](/documentation/CoreImage/CIVector) instance containing the `x,y` coordinate. [`kCIInputRadiusKey`](/documentation/CoreImage/kCIInputRadiusKey) The distance from the center of an effect. [`kCIInputRadius0Key`](/documentation/CoreImage/kCIInputRadius0Key) A key to get or set the geometric radius value of a Core Image filter. [`kCIInputRadius1Key`](/documentation/CoreImage/kCIInputRadius1Key) A key to get or set the geometric radius value of a Core Image filter. [`kCIInputRefractionKey`](/documentation/CoreImage/kCIInputRefractionKey) The index of refraction to use. [`kCIInputSaturationKey`](/documentation/CoreImage/kCIInputSaturationKey) The amount to adjust the saturation. [`kCIInputScaleKey`](/documentation/CoreImage/kCIInputScaleKey) The amount of scale to apply. [`kCIInputShadingImageKey`](/documentation/CoreImage/kCIInputShadingImageKey) A key for a [`CIImage`](/documentation/CoreImage/CIImage) object that specifies an environment map with alpha values. Typically this image contains highlight and shadow. [`kCIInputSharpnessKey`](/documentation/CoreImage/kCIInputSharpnessKey) Amount of sharpening to apply. [`kCIInputTargetImageKey`](/documentation/CoreImage/kCIInputTargetImageKey) A key for a [`CIImage`](/documentation/CoreImage/CIImage) object that is the target image for a transition. [`kCIInputThresholdKey`](/documentation/CoreImage/kCIInputThresholdKey) A key to get or set the scalar threshold value of a Core Image filter. [`kCIInputTimeKey`](/documentation/CoreImage/kCIInputTimeKey) Specify a time. [`kCIInputTransformKey`](/documentation/CoreImage/kCIInputTransformKey) Transformation to apply. [`kCIInputVersionKey`](/documentation/CoreImage/kCIInputVersionKey) Version Key [`kCIInputWeightsKey`](/documentation/CoreImage/kCIInputWeightsKey) A key for a [`CIVector`](/documentation/CoreImage/CIVector) object that describes a weight matrix for use with a convolution filter. [`kCIInputWidthKey`](/documentation/CoreImage/kCIInputWidthKey) A key for a scalar value that specifies the width of the effect. [`kCIOutputImageKey`](/documentation/CoreImage/kCIOutputImageKey) A key for the [`CIImage`](/documentation/CoreImage/CIImage) object produced by a filter. ### Deprecated [`kCIInputBaselineExposureKey`](/documentation/CoreImage/CIRAWFilterOption/baselineExposure) The amount of baseline exposure applied. [`kCIInputDisableGamutMapKey`](/documentation/CoreImage/CIRAWFilterOption/disableGamutMap) Whether or not to disable gamut mapping. [`kCIInputMoireAmountKey`](/documentation/CoreImage/CIRAWFilterOption/moireAmount) The amount of moiré reduction to apply. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)