CIDetector识别图片(读取图片信息)探测器对象

@IBAction func photoBtnClick(sender: AnyObject) {
       // 打开相册
       // 1.判断是否能够打开相册
       /*
       case PhotoLibrary  相册
       case Camera 相机
       case SavedPhotosAlbum 图片库
       */
       if !UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.PhotoLibrary)
       {
           return
       }
       
       // 2.创建相册控制器
       let imagePickerVC = UIImagePickerController()
       
       imagePickerVC.delegate = self
       // 3.弹出相册控制器
       presentViewController(imagePickerVC, animated: true, completion: nil)
       
   }

• CIDetector 探测器对象

extension QRCodeViewController: UINavigationControllerDelegate, UIImagePickerControllerDelegate
{
    // 过时
//    func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage, editingInfo: [String : AnyObject]?) {
//        
//    }
    
    func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
//        NJLog(info)
        
        // 1.取出选中的图片
        guard let image = info[UIImagePickerControllerOriginalImage] as? UIImage else
        {
            return
        }
        
        guard let ciImage = CIImage(image: image) else
        {
            return
        }
        
        // 2.从选中的图片中读取二维码数据
        // 2.1创建一个探测器对象,类型二维码探测(还有人脸,text等)
        //options:选项低像素和高像素,一个块一个慢
        let detector = CIDetector(ofType: CIDetectorTypeQRCode, context: nil, options: [CIDetectorAccuracy: CIDetectorAccuracyLow])
        // 2.2利用探测器探测数据
        let results = detector.featuresInImage(ciImage)
        // 2.3取出探测到的数据
        for result in results
        {
            NJLog((result as! CIQRCodeFeature).messageString)
        }
        
        // 注意: 如果实现了该方法, 当选中一张图片时系统就不会自动关闭相册控制器
        picker.dismissViewControllerAnimated(true, completion: nil)
    }
}