text: //
  //  RectangleDetector.h
  //  PDFScanner
  //
  //  Created by Y on 2018/11/5.
  //  Copyright © 2018 Y. All rights reserved.
  //
  
  #import <Foundation/Foundation.h>
  #import <UIKit/UIKit.h>
  #import <Vision/Vision.h>
  
  @interface RectangleDetector : NSObject
  
  @property (nonatomic, strong, nullable) VNRectangleObservation * lastObservation;
  
  @property (nonatomic, strong, nullable) VNSequenceRequestHandler * sequenceHandler;
  
  + (instancetype)shareDetector;
  
  - (void)visionImageEdge:(CVPixelBufferRef)image;
  
  - (void)visionImageEdge:(CVPixelBufferRef)image lastObservation:(nullable VNRectangleObservation *)observation handler:(nullable VNRequestCompletionHandler)completionHandler;
  
  @end
  