     }
 }
 
-extension UInt8: PixelType {
+extension UInt8 {
     typealias SummableI = Int
     typealias SummableF = Float
     typealias SummableD = Double

    }
}

extension Float: PixelType {
    typealias SummableI = Float
    typealias SummableF = Float
    typealias SummableD = Double

    }
}

extension Int {
    typealias SummableI = Int
    typealias SummableF = Float
    typealias SummableD = Double
