Gray Color Matrix

blackandwhite

// vim: syntax=Swift

Swift Color matrix

let redCoefficient: Float = 0.2126
let greenCoefficient: Float = 0.7152
let blueCoefficient: Float = 0.0722

let divisor: Int32 = 0x1000
let fDivisor = Float(divisor)

var coefficientsMatrix = [
    Int16(redCoefficient * fDivisor),
    Int16(greenCoefficient * fDivisor),
    Int16(blueCoefficient * fDivisor)
]

let preBias: [Int16] = [0, 0, 0, 0]
let postBias: Int32 = 0

guard let monoFormat = vImage_CGImageFormat(
    bitsPerComponent: 8,
    bitsPerPixel: 8,
    colorSpace: CGColorSpaceCreateDeviceGray(),
    bitmapInfo: CGBitmapInfo(rawValue: CGImageAlphaInfo.none.rawValue),
    renderingIntent: .defaultIntent) else {
        return
}

let result = try? destinationBuffer.createCGImage(format: monoFormat)

if let result = result {
    imageView.image = UIImage(cgImage: result)
}