2020.6.21_P77_OpenCV投影变换-通过鼠标事件在原图和输出的画布上选取四组对应的坐标

2020.6.21_P77_OpenCV投影变换-通过鼠标事件在原图和输出的画布上选取四组对应的坐标

//2020.6.21_P77_OpenCV投影变换
//通过鼠标事件在原图和输出的画布上选取四组对应的坐标
//投影矩阵的数据类型为CV_64F
//txwtech

//2020.6.21_P77_OpenCV投影变换
//通过鼠标事件在原图和输出的画布上选取四组对应的坐标
//投影矩阵的数据类型为CV_64F
//txwtech
#include <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/highgui.hpp>
using namespace cv;
 
Mat I;
Mat pI;
Point2f IPoint, pIPoint;
int i = 0, j = 0;
Point2f src[4];
Point2f dst[4];
void mouse_I(int event, int x, int y, int flags, void *param)
{
    switch (event)
    {
    case CV_EVENT_LBUTTONDOWN:
            IPoint = Point2f(x,y);
            break;
    case CV_EVENT_LBUTTONUP:
            src[i] = IPoint;
            circle(I,src[i],7,Scalar(0),3);
            i += 1;
            break;
    default:
        break;
 
 
 
    }
}
void mouse_pI(int event, int x, int y, int flags, void *param)
{
    switch (event)
    {
    case CV_EVENT_LBUTTONDOWN:
        pIPoint = Point2f(x,y);
        break;
    case CV_EVENT_LBUTTONUP:
        dst[j] = pIPoint;
        circle(pI,dst[j],7,Scalar(0),3);
        j += 1;
        break;
    default:
        break;
    }
}
int main(int argc, char *agrv[])
{
    I = imread("D:\pictures\book1.jpg",CV_LOAD_IMAGE_GRAYSCALE);
    if (!I.data)
        return -1;
    pI = 255*Mat::ones(I.size(),CV_8UC1);
    namedWindow("I",1); //window auto size=1
    setMouseCallback("I",mouse_I,NULL);
    namedWindow("pI",1);
    
    setMouseCallback("pI",mouse_pI,NULL);
    imshow("I",I);
    imshow("pI",pI);
    while (!(i == 4 && j == 4))
    {
        imshow("I",I);//原图
        imshow("pI",pI);//投影变换后的图
        if (waitKey(50) == 'q')
            break;
    }
    imshow("I",I);
    imshow("pI",pI);
    setMouseCallback("I",NULL,NULL);
    setMouseCallback("pI", NULL, NULL);
    Mat p = getPerspectiveTransform(src,dst);//计算投影变换矩阵
    Mat result;
    warpPerspective(I,result,p,pI.size());//投影变换
    imshow("投影后的效果",result);
    waitKey(0);
    return 0;
 
}