ios-深度解析二维码的生成与使用

// 1.创建Transform orginalImage的数据类型为CIImage
let scale = imageView.bounds.width / orginalImage.extent.width
let transform = CGAffineTransformMakeScale(scale, scale)
// 2.放大图片
let hdImage = orginalImage.imageByApplyingTransform(transform)

// 1.创建照片选择控制器
let ipc = UIImagePickerController()
// 2.设置来源的类型
ipc.sourceType = .PhotoLibrary
// 3.设置代理
ipc.delegate = self
// 4.弹出控制器
presentViewController(ipc, animated: true, completion: nil) 在代理方法中实现 选中图片dismiss掉控制器
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
//选中照片
imageView.image = info[UIImagePickerControllerOriginalImage] as? UIImage picker.dismissViewControllerAnimated(true, completion: nil)
}

// 1.创建识别器
let detector = CIDetector(ofType: CIDetectorTypeQRCode, context: nil, options: nil) // 2.获取图片,并且将图片转成CIIImage
let image = imageView.image!
guard let ciImage = CIImage(image: image) else {
return
}
// 3.识别图片中二维码
let features = detector.featuresInImage(ciImage) // 4.遍历数组中所有的元素
for f in features {
// feature类型是CIFeature 要转换成二维码类型 CIQRCodeFeature
guard let qrCodeF = f as? CIQRCodeFeature else {
continue
}
//打印二维码的信息
print(qrCodeF.messageString)
}

// 1.改变约束(原来约束为-240)
scanViewBottomCons.constant =
// 2.执行动画
UIView.animateWithDuration(1.0) {
UIView.setAnimationRepeatCount(MAXFLOAT)
self.qrCodeView.layoutIfNeeded()
}

// 1.创建捕捉会话
let session = AVCaptureSession() // 2.设置输入(摄像头)
let device = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)
guard let input = try? AVCaptureDeviceInput(device: device) else {
return
}
session.addInput(input) // 3.设置输出(Metadata)
let output = AVCaptureMetadataOutput()
// 设置代理
output.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())
session.addOutput(output)
// 设置output的输出的类型(该类型的设置必须在添加到session之后)
output.metadataObjectTypes = [AVMetadataObjectTypeQRCode] // 4.添加预览图层(可以没有)
let previewLayer = AVCaptureVideoPreviewLayer(session: session)
previewLayer.frame = view.bounds
view.layer.insertSublayer(previewLayer, atIndex: ) // 5.开始扫描
session.startRunning()

func captureOutput(captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [AnyObject]!, fromConnection connection: AVCaptureConnection!) {
guard let objc = metadataObjects.last as? AVMetadataMachineReadableCodeObject else {
return
}
print(objc.stringValue)
}

// 设置扫描的区域
let screenW = UIScreen.mainScreen().bounds.width
let screenH = UIScreen.mainScreen().bounds.height
let x : CGFloat = qrCodeView.frame.origin.x / screenW
let y : CGFloat = qrCodeView.frame.origin.y / screenH
let w : CGFloat = qrCodeView.frame.width / screenW
let h : CGFloat = qrCodeView.frame.height / screenH
output.rectOfInterest = CGRect(x: y, y: x, width: h, height: w)