// 影象金字塔上取樣降取樣.cpp: 定義控制檯應用程式的入口點。
//

#include "stdafx.h"
#include "opencv2/opencv.hpp"]
#include "iostream"
using namespace cv;
using namespace std;


int main()
{
    Mat src,downImage, upImage;
    src = imread("angelababy.jpg");
    imshow("src", src);

    //每次只能放大或縮小一倍，不能跳著放大
    pyrDown(src, downImage, Size(src.cols >> 1
 
, src.rows >> 1)); //降取樣 縮小
    pyrUp(src, upImage, Size(src.cols << 1, src.rows << 1));  //上取樣 放大
    imshow("pryDown", downImage);
    imshow("pryUp", upImage);

    //Difference of Gaussian(DOG) 高斯不同
    Mat gray_image, g1, g2 , dogImage;
    cvtColor(src, gray_image, CV_BGR2GRAY);
    GaussianBlur(gray_image, g1, Size(3
 
,3),0);
    GaussianBlur(g1, g2, Size(3, 3), 0);
    subtract(g1, g2, dogImage);
    normalize(dogImage, dogImage, 255, 0, NORM_MINMAX);
    bitwise_not(dogImage, dogImage);
    imshow("DOG", dogImage);

    waitKey();
    return 0;
}