Private Core Image Filters

After reading this post about hidden Quartz Composer patches, I starting digging and found 42 private Core Image filters:

    NSLog(@"%@", [CIFilter filterNamesInCategory: @"CICategoryApplePrivate"]);

(
    CIAddBlendMode, 
    CIAlphaAddBlendMode, 
    CIBayerReconstruction, 
    CIBayerReconstructionV0, 
    CIBehindBlendMode, 
    CIBilateralFilter, 
    CICheapBlur, 
    CIColorWheelGenerator, 
    CIDeBayer, 
    CIDesaturateGamutMapping, 
    CIDistanceFieldFromMask, 
    CIEmboss, 
    CIGamutAlarm, 
    CIGamutClamp, 
    CIGamutRollOff, 
    CIGaussianPyramid, 
    CIHardMixBlendMode, 
    CIHeightFieldFromConstraints, 
    CILanczosBayerReconstruction, 
    CILinearBurnBlendMode, 
    CILinearDodgeBlendMode, 
    CILinearLightBlendMode, 
    CILuminanceGamutMapping, 
    CILuminescentPremultiplyBlendMode, 
    CIMixOver, 
    CIOpacity, 
    CIPinLightBlendMode, 
    CIPixelZoom, 
    CIRAWSharpen, 
    CIRectangleGenerator, 
    CIRefractedMaterial, 
    CIRotatingCubeTransition, 
    CIShapedWaterRipple, 
    CISilhouetteAlphaBlendMode, 
    CISilhouetteLumaBlendMode, 
    CIStencilAlphaBlendMode, 
    CIStencilLumaBlendMode, 
    CISubtractBlendMode, 
    CISumOf8Conics, 
    CIVideoNoiseFilter, 
    CIVividLightBlendMode, 
    CIWhitePoint
)

Happy hacking! As with any private API, use at your own risk.