網上找過很多資料，不是缺少庫的引用就是缺少備註表述

所以自己實現一下並記錄下來

//
//  ViewController.m
//  h
//
//  Created by Friderick_Lee on 2017/12/16.
//  Copyright © 2017年 Friderick_Lee. All rights reserved.
//
#import <opencv2/imgproc/types_c.h>
#import <opencv2/opencv.hpp>
#import <OpenCV/opencv2/imgcodecs/ios.h>
#import "ViewController.h"
 

using namespace cv;
@interface ViewController ()
{
    cv::Mat cvImage;
}
@property (weak, nonatomic) IBOutlet UIImageView *imgView;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    CGRect
 
 rect = [UIScreen mainScreen].bounds;
    self.imgView.frame = rect;

    UIImage *image = [UIImage imageNamed:@"n.png"];
    //將UIImge轉換成mat型別方便c++處理
    UIImageToMat(image, cvImage);

    if(!cvImage.empty()){
        cv::Mat gray;
        // 將影象轉換為灰度顯示
        cv::cvtColor(cvImage,gray,CV_RGB2GRAY);
        // 應用高斯濾波器去除小的邊緣
 

        cv::GaussianBlur(gray, gray, cv::Size(5,5), 1.2,1.2);
        // 計算與畫布邊緣
        cv::Mat edges;
        cv::Canny(gray, edges, 0, 50);
        // 使用白色填充
        cvImage.setTo(cv::Scalar::all(225));
        // 修改邊緣顏色
        cvImage.setTo(cv::Scalar(0,128,255,255),edges);
        // 將Mat轉換為Xcode的UIImageView顯示
        self.imgView.image = MatToUIImage(cvImage);

    }
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


@end

原圖效果

效果圖