Ufdjrw

I want to edit an image with a LUT filter as a CIFilter to edit the color of the image. Unfortunately, I stumble with the conversion in Swift. When I execute the code, the processedImage results in nil at the end.

Here is my code from my ViewController:

Example Image: LUT.png

let nameLUT = "LUT.png"
let inputImage = CIImage(image: image)
let context = CIContext(options: nil)

if let currentFilter = CIFilter(name: nameLUT) 

 let beginImage = inputImage
 currentFilter.setValue(beginImage, forKey: kCIInputImageKey)
 currentFilter.setValue(0.5, forKey: kCIInputIntensityKey)

 if let output = currentFilter.outputImage 
 if let cgimg = context.createCGImage(output, from: output.extent) 
 let processedImage = UIImage(cgImage: cgimg)
 
 

Here is the implementation of the functions to CIFilter from my .swift extension:

extension CIFilter {
func colorCubeFilterFromLUT(name : String) -> CIFilter? 

class func getBytesFromImage(from image:CGImage?) -> [UInt8]?
 print("Filter: func getBytesFromImage")
 var pixelValues: [UInt8]?
 if let imageRef = image CGBitmapInfo.byteOrder32Little.rawValue
 let colorSpace = CGColorSpaceCreateDeviceRGB()
 var intensities = [UInt8](repeating: 0, count: totalBytes)

 let contextRef = CGContext(data: &intensities, width: width, height: height, bitsPerComponent: bitsPerComponent, bytesPerRow: bytesPerRow, space: colorSpace, bitmapInfo: bitmapInfo)
 contextRef?.draw(imageRef, in: CGRect(x: 0.0, y: 0.0, width: CGFloat(width), height: CGFloat(height)))

 pixelValues = intensities
 
 return pixelValues!