1.放缩变换

  1. #include <opencv2\opencv.hpp>
  2. #include <iostream>
  4. using namespace std;
  5. using namespace cv;
  7. int main()
  8. {
  9.     Mat gray = imread("lena.png", IMREAD_GRAYSCALE);
  10.     if (gray.empty())
  11.     {
  12.         cout << "请确认图像文件名称是否正确" << endl;
  13.         return -1;
  14.     }
  16.     Mat smallImg, bigImg0, bigImg1, bigImg2;
  17.     resize(gray, smallImg, Size(15, 15), 0, 0, INTER_AREA);  //先将图像缩小
  18.     resize(smallImg, bigImg0, Size(30, 30), 0, 0, INTER_NEAREST);  //最近邻差值
  19.     resize(smallImg, bigImg1, Size(30, 30), 0, 0, INTER_LINEAR);  //双线性差值
  20.     resize(smallImg, bigImg2, Size(30, 30), 0, 0, INTER_CUBIC);  //双三次差值
  21.     namedWindow("smallImg", WINDOW_NORMAL);  //图像尺寸太小，一定要设置可以调节窗口大小标志
  22.     imshow("smallImg", smallImg);
  23.     namedWindow("bigImg0", WINDOW_NORMAL);
  24.     imshow("bigImg0", bigImg0);
  25.     namedWindow("bigImg1", WINDOW_NORMAL);
  26.     imshow("bigImg1", bigImg1);
  27.     namedWindow("bigImg2", WINDOW_NORMAL);
  28.     imshow("bigImg2", bigImg2);
  29.     waitKey(0);
  30.     return 0;
  31. }

图3-21.png

2.翻转变换

  1. #include <opencv2\opencv.hpp>
  2. #include <iostream>
  4. using namespace std;
  5. using namespace cv;
  7. int main()
  8. {
  9.     Mat img = imread("lena.png");
  10.     if (img.empty())
  11.     {
  12.         cout << "请确认图像文件名称是否正确" << endl;
  13.         return -1;
  14.     }
  16.     Mat img_x, img_y, img_xy;
  17.     flip(img, img_x, 0);  //沿x轴对称
  18.     flip(img, img_y, 1);  //沿y轴对称
  19.     flip(img, img_xy, -1);  //先x轴对称，再y轴对称
  20.     imshow("img", img);
  21.     imshow("img_x", img_x);
  22.     imshow("img_y", img_y);
  23.     imshow("img_xy", img_xy);
  24.     waitKey(0);
  25.     return 0;
  26. }

图3-22.png

3.仿射变换

4.透视变换