// Create a CIImage from a file.
CIImage flower = CIImage.FromCGImage (UIImage.FromFile ("flower.png").CGImage);
        
// Create the points used to create the tone curve.
var point0 = new CIVector(0,0); // Default [0 0]
var point1 = new CIVector(.1F, .5F); // Default [.25 .25]
var point2 = new CIVector(.3F, .15F); // Default [.3 .15]
var point3 = new CIVector(.6F, .6F); // Default [.75 .75]
var point4 = new CIVector(1.1F, 1F); // Default [1 1]

// Construct the ToneCurve filter
var toneCurve = new CIToneCurve()
{
	Image = flower,
	Point0 = point0,
	Point1 = point1,
	Point2 = point2,
	Point3 = point3,
	Point4 = point4,
};

// Get the adjusted image from the filter.
var output = toneCurve.OutputImage;
	
// To render the results, we need to create a context, and then
// use one of the context rendering APIs, in this case, we render the
// result into a CoreGraphics image, which is merely a useful representation
//
var context = CIContext.FromOptions (null);

var cgimage = context.CreateCGImage (output, output.Extent);

// The above cgimage can be added to a screen view, for example, this
// would add it to a UIImageView on the screen:
myImageView.Image = UIImage.FromImage (cgimage);