边缘检测时可以采用sobel算子,主要用到的opencv函数是GaussianBlur、Sobel、convertScaleAbs、addWeighted首先高斯滤波再分别进行x方向和y方向计算梯度,然后取绝对值后加权融合。代码如下:
#include "opencv2/imgproc/imgproc.hpp" #include "opencv2/highgui/highgui.hpp" #include <stdlib.h> #include <stdio.h> using namespace cv; /** @function main */ int main( int argc, char** argv ) { Mat src, src_gray; Mat grad; char* window_name = "Sobel Demo - Simple Edge Detector"; int scale = 1; int delta = 0; int ddepth = CV_16S; int c; /// Load an image src = imread( argv[1] ); if( !src.data ) { return -1; } GaussianBlur( src, src, Size(3,3), 0, 0, BORDER_DEFAULT ); /// Convert it to gray cvtColor( src, src_gray, CV_RGB2GRAY ); /// Create window namedWindow( window_name, CV_WINDOW_AUTOSIZE ); /// Generate grad_x and grad_y Mat grad_x, grad_y; Mat abs_grad_x, abs_grad_y; /// Gradient X //Scharr( src_gray, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT ); Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT ); convertScaleAbs( grad_x, abs_grad_x ); /// Gradient Y //Scharr( src_gray, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT ); Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT ); convertScaleAbs( grad_y, abs_grad_y ); /// Total Gradient (approximate) addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad ); imshow( window_name, grad ); waitKey(0); retutn 0; }