边缘检测一般步骤
1,canny()边缘检测
实例
#include<opencv2/opencv.hpp>
using namespace std;
using namespace cv;
//全局变量声明
Mat src,dst, edge, gray;
int g_nsizeValue = 9;
int g_nsizeValue2 = 3;//阈值上下线
//轨迹条的回调函数(静态函数,只适用于本文件)
static void on_canny(int, void*);
//主函数
int main()
{
system("color 5E");
src= imread("D://1.jpg", 1);
if (!src.data) { printf("错错错\n"); return false; }
cvtColor(src, gray, COLOR_RGB2GRAY);
//显示原图
namedWindow("窗口", WINDOW_AUTOSIZE);
//1模式
createTrackbar("阈值上限:", "窗口", &g_nsizeValue, 255, on_canny);
createTrackbar("阈值下限:", "窗口", &g_nsizeValue2, 255, on_canny);
//2模式
createTrackbar("阈值上限:", "灰窗口", &g_nsizeValue, 255, on_canny);
createTrackbar("阈值下限:", "灰窗口", &g_nsizeValue2, 255, on_canny);
//初始化自定义函数
on_canny(0, 0);
//输出提示信息
cout << endl << "滑动滚动条观察图像效果\n\n"
<< "按下q键退出";
while (char(waitKey(1)) != 'q') {}
return 0;
}
//函数定义
static void on_canny(int, void*)
{
blur(gray, edge, Size(3, 3));
Canny(edge, edge, g_nsizeValue, g_nsizeValue2, 3);
imshow("灰度图窗口", edge);
dst = Scalar::all(0);
src.copyTo(dst, edge);
imshow("窗口", dst);//refresch the function of image
}
2,
3
4,
整体运用例子
#include<opencv2/opencv.hpp>
using namespace std;
using namespace cv;
//全局变量声明
Mat src,dst,gray,dst2,grad_x, grad_y, absgrad_x, absgrad_y,abs_dst;
//主函数
int main()
{
system("color 5E");
src= imread("D://1.jpg", 1);
if (!src.data) { printf("错错错\n"); return false; }
imshow("原图窗口", src);
//Sobel,sharr和sobel类似,只是少个3(内核值大小设定)
Sobel(src, grad_x, CV_16S, 1, 0, 3, 1, 1, BORDER_DEFAULT);
convertScaleAbs(grad_x, absgrad_x);
imshow("x方向sobel窗口", absgrad_x);
Sobel(src, grad_y, CV_16S, 0, 1, 3, 1, 1, BORDER_DEFAULT);
convertScaleAbs(grad_y, absgrad_y);
imshow("y方向sobel窗口", absgrad_y);
addWeighted(absgrad_x, 0.5, absgrad_y, 0.5,0, dst);
imshow("x+y整体情况窗口", dst);
//scharr,sobel类似,只是少个3(内核值大小设定)
Scharr(src, grad_x, CV_16S, 1, 0, 1, 1, BORDER_DEFAULT);
convertScaleAbs(grad_x, absgrad_x);
imshow("x方向scharr窗口", absgrad_x);
Scharr(src, grad_y, CV_16S, 0, 1, 1, 1, BORDER_DEFAULT);
convertScaleAbs(grad_y, absgrad_y);
imshow("y方向scharr口", absgrad_y);
addWeighted(absgrad_x, 0.5, absgrad_y, 0.5, 0, dst);
imshow("x+y整体scharr情况窗口", dst);
//Laplace
cvtColor(src, gray, COLOR_RGB2GRAY);
Laplacian(gray, dst2, CV_16S, 3, 1, 0, BORDER_DEFAULT);
convertScaleAbs(dst2, abs_dst);
imshow("Laplace窗口", abs_dst);
//输出提示信息
cout << endl << "滑动滚动条观察图像效果\n\n"
<< "按下q键退出";
while (char(waitKey(1)) != 'q') {}
return 0;
}