How do you change the Back and Foreground Color of a CIFilter CIQRCodeGenerator Filter

Question

I\'m trying to make a QR Code Generator for OS X but i haven\'t had succession in making a QRCode that can be more colourful that the black and white ones I\'m using the CIQRCod

Answer 1

Here's an example in swift (for the googlers)

func qrCode(from string: String) -> UIImage? {
    let data = string.data(using: .ascii)

    // Generate the code image with CIFilter
    guard let filter = CIFilter(name: "CIQRCodeGenerator") else { return nil }
    filter.setValue(data, forKey: "inputMessage")

    // Scale it up (because it is generated as a tiny image)
    let scale = UIScreen.main.scale
    let transform = CGAffineTransform(scaleX: scale, y: scale)
    guard let output = filter.outputImage?.transformed(by: transform) else { return nil }

    // Change the color using CIFilter
    let colorParameters = [
        "inputColor0": CIColor(color: UIColor.black), // Foreground
        "inputColor1": CIColor(color: UIColor.clear) // Background
    ]
    let colored = output.applyingFilter("CIFalseColor", parameters: colorParameters)

    return UIImage(ciImage: colored)
}