Python使用OpenCV对图像进行缩放功能

#include<opencv2\opencv.hpp>   
#include<opencv2\highgui\highgui.hpp>
using namespace std;
using namespace cv;
 
//图片的缩小与放大
int main()
{
    Mat img = imread("lol5.jpg");
    imshow("原始图", img);
 
    Mat dst = Mat::zeros(512, 512, CV_8UC3); //我要转化为512*512大小的
    resize(img, dst, dst.size());
 
    imshow("尺寸调整之后", dst);
 
    waitKey(0);
 
}

#include<opencv2\opencv.hpp>   
#include<opencv2\highgui\highgui.hpp>
 
using namespace std;
using namespace cv;
//图片的缩小与放大
int main()
{
    Mat img = imread("lol5.jpg");
    imshow("原始图", img);
    Mat dst;
    resize(img, dst, Size(),0.5,0.5);//我长宽都变为原来的0.5倍
    imshow("尺寸调整之后", dst);
    waitKey(0);
}

#include<opencv2\opencv.hpp>   
#include<opencv2\highgui\highgui.hpp>
 
using namespace std;
using namespace cv;
//图像金字塔
int main()
{
    Mat img = imread("lol8.jpg");
    imshow("原始图", img);
    Mat dst,dst2;
    pyrUp(img, dst, Size(img.cols*2, img.rows*2)); //放大一倍
    pyrDown(img, dst2, Size(img.cols * 0.5, img.rows * 0.5)); //缩小为原来的一半
    imshow("尺寸放大之后", dst);
    imshow("尺寸缩小之后", dst2);
    waitKey(0);
}