学习c++版opencv3.4之19-Laplance算子

Laplance算子：求图像二阶导数图像。

#include <opencv2/opencv.hpp>
#include <iostream>
#include <math.h>

using namespace std;
using namespace cv;

int threshold_value = 100, threshold_max = 255;
int threshold_type = 0, threshold_type_max = 4;
string outwindow = "threshold img";
Mat src, dst;
void mythreshold(int, void*);
int main(){
    Mat src1;
    src1 = imread("/Users/ming/Documents/test.jpg");
    resize(src1, src, Size(src1.cols/2, src1.rows/2));
    if (!src.data){
        printf("cannot load image ...");
        return -1;
    }
    namedWindow("src img", CV_WINDOW_AUTOSIZE);
    imshow("src img", src);
    
    GaussianBlur(src, dst, Size(3,3), 0);
    Mat src_gray;
    cvtColor(src, src_gray, CV_BGR2GRAY);
    imshow("gaussian+gray", src_gray);
    //laplance算子
    Laplacian(src_gray, dst, -1);
    imshow("laplance", dst);
    threshold(dst, dst, 0, 255, THRESH_OTSU | THRESH_BINARY);
    imshow("threshold", dst);
//    Mat dst_final;
//    convertScaleAbs(dst, dst_final);
//    imshow("laplance final", dst_final);
    
    waitKey(0);
    return 0;
}