iOS 7 Core Image QR Code generation too blur

Question

here\'s my code for generating QRCode image

+ (UIImage *)generateQRCodeWithString:(NSString *)string {
    NSData *stringData = [string dataUsingEncoding:NSU         


        

Answer 1

Rewrite @Benoît Caron's answer in Swift 3.1:

func convertTextToQRCode(text: String, withSize size: CGSize) -> UIImage {

    let data = text.data(using: String.Encoding.isoLatin1, allowLossyConversion: false)

    let filter = CIFilter(name: "CIQRCodeGenerator")!

    filter.setValue(data, forKey: "inputMessage")
    filter.setValue("L", forKey: "inputCorrectionLevel")

    let qrcodeCIImage = filter.outputImage!

    let cgImage = CIContext(options:nil).createCGImage(qrcodeCIImage, from: qrcodeCIImage.extent)
    UIGraphicsBeginImageContext(CGSize(width: size.width * UIScreen.main.scale, height:size.height * UIScreen.main.scale))
    let context = UIGraphicsGetCurrentContext()
    context!.interpolationQuality = .none

    context?.draw(cgImage!, in: CGRect(x: 0.0,y: 0.0,width: context!.boundingBoxOfClipPath.width,height: context!.boundingBoxOfClipPath.height))

    let preImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    let qrCodeImage = UIImage(cgImage: (preImage?.cgImage!)!, scale: 1.0/UIScreen.main.scale, orientation: .downMirrored)

    return qrCodeImage
}