OpenCV2.4.4实现Harris角点检测

代码如下：

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
using namespace cv;
using namespace std;
//全局变量
Mat src, src_gray;//源图和灰度图
int thresh = 200;//默认阈值
int max_thresh = 255;//滑块条最大值
void cornerHarris_demo( int, void* )
{
    Mat dst, dst_norm, dst_norm_scaled;
    dst = Mat::zeros( src.size(), CV_32FC1 );
    //参数
    int blockSize = 2;
    int apertureSize = 3;
    double k = 0.04;
    //Harris角点检测
    cornerHarris( src_gray, dst, blockSize, apertureSize, k, BORDER_DEFAULT );
    //像素归一化到[0,255]
    normalize( dst, dst_norm, 0, 255, NORM_MINMAX, CV_32FC1, Mat() );
    convertScaleAbs( dst_norm, dst_norm_scaled );//去绝对值后变换为8位无符号类型
    Mat src_copy = src.clone();
    //在角点上画圈
    for( int j = 0; j < dst_norm.rows ; j++ )
    {
        for( int i = 0; i < dst_norm.cols; i++ )
        {
            if( (int) dst_norm.at<float>(j,i) > thresh )
            {
                circle(dst_norm_scaled,Point(i,j),3,Scalar(0));
                circle(src_copy,Point(i,j),3,Scalar(0,255,0));
            }
        }
    }
    /// Showing the result
    namedWindow( "Corners", CV_WINDOW_AUTOSIZE );
    imshow( "Corners", dst_norm_scaled );
    imshow( "Src", src_copy );
}
int main()
{
    //加载源图像并转换为灰度图
    src = imread("horse.jpg");
    cvtColor( src, src_gray, CV_BGR2GRAY );
    //显示源图
    namedWindow( "Src", CV_WINDOW_AUTOSIZE );
    imshow( "Src", src );
    //创建滑块条，并指定回调函数为cornerHarris_demo()，每次滑块位置改变时都会调用此函数
    createTrackbar( "阈值：", "Src", &thresh, max_thresh, cornerHarris_demo );
    //调用函数，计算角点
    cornerHarris_demo( 0, 0 );
    waitKey(0);
    return(0);
}

效果图：