main.rar

#include "opencv2/core/core.hpp" #include "opencv2/highgui/highgui.hpp" #include "opencv2/imgproc/imgproc.hpp" #include <iostream> #include <vector> #include <string> class ExtractLines{ private: cv::Mat Src, //Define Mat to hold source image Img, //Original image Dst, //Processed image Dx, //Partial derivative with respect to x Dy, //Partial derivative with respect to y Dxx, //Second derivate with respect to x Dxy, //Second partial derivative with respect to x and y, Dxy = Dyx Dyy; //Second derivative with respect to y std::vector<cv::Point> *DetectPoints; void ComputeDerivative(void); void ComputeHessian(void); public: ExtractLines(const cv::Mat& Img); void imshow(void) const; inline ~ExtractLines(){delete DetectPoints;} }; /** * @brief Compute first and second partial derivative matrixes. * Call ComputeHessian() after all the derivative matrixes * has been computed. **/ void ExtractLines::ComputeDerivative(void){ cv::Mat Mask_Dx = (cv::Mat_<float>(3, 1) << 1, 0 , -1); cv::Mat Mask_Dy = (cv::Mat_<float>(1, 3) << 1, 0 , -1); cv::Mat Mask_Dxx = (cv::Mat_<float>(3, 1) << 1, -2 , 1); cv::Mat Mask_Dyy = (cv::Mat_<float>(1, 3) << 1, -2 , 1); cv::Mat Mask_Dxy = (cv::Mat_<float>(2, 2) << 1, -1 , -1, 1); cv::filter2D(Dst, Dx, CV_32FC1, Mask_Dx); cv::filter2D(Dst, Dy, CV_32FC1, Mask_Dy); cv::filter2D(Dst, Dxx, CV_32FC1, Mask_Dxx); cv::filter2D(Dst, Dxy, CV_32FC1, Mask_Dxy); cv::filter2D(Dst, Dyy, CV_32FC1, Mask_Dyy); ComputeHessian(); } /** * @brief Compute first and second partial derivative matrixes. * Call ComputeHessian() after all the derivative matrixes * has been computed. **/ void ExtractLines::ComputeHessian(void){ for(int x = 0; x < Dst.cols; x++) { for(int y = 0; y < Dst.rows; y++) { if(Src.at<uchar>(y,x) > 10) { cv::Mat Hessian(2,2,CV_32FC1),Eigenvalue,Eigenvector; Hessian.at<float>(0, 0) = Dxx.at<float>(y, x); Hessian.at<float>(0, 1) = Dxy.at<float>(y, x); Hessian.at<float>(1, 0) = Dxy.at<float>(y, x); Hessian.at<float>(1, 1) = Dyy.at<float>(y, x); cv::eigen(Hessian, Eigenvalue, Eigenvector); double Nx, Ny; if(fabs(Eigenvalue.at<float>(0, 0)) >= fabs(Eigenvalue.at<float>(1, 0))) { Nx = Eigenvector.at<float>(0, 0); Ny = Eigenvector.at<float>(0, 1); } else { Nx = Eigenvector.at<float>(1, 0); Ny = Eigenvector.at<float>(1, 1); } double denominator = Dxx.at<float>(y,x) * Nx * Nx + 2 * Dxy.at<float>(y,x) * Nx * Ny + Dyy.at<float>(y,x) * Ny * Ny, t; if(denominator != 0.0) { t = -(Dx.at<float>(y,x) * Nx + Dy.at<float>(y,x) * Ny) / denominator; if(fabs(t * Nx) <= 0.5 && fabs(t * Ny) <= 0.5) { cv::Point_<float> res(x,y); (*DetectPoints).push_back(res); } } } } } } /** * @brief Constructor, init the image and preprocess the input image with Gaussian filter. Throw error if cannot open the image. @param img_name: the input file name. **/ ExtractLines::ExtractLines(const cv::Mat& Input_img){ Src = Input_img.clone(); Img = Input_img.clone(); cv::cvtColor(Src, Src, CV_BGR2GRAY); //Convert RGB image to gray space Dst = Src.clone(); cv::GaussianBlur(Dst, Dst, cv::Size(0, 0), 3, 3); DetectPoints = new std::vector<cv::Point>; ComputeDerivative(); } /** * @brief Draw detected salient points on original image using cv::circle and display the result. **/ void ExtractLines::imshow(void) const{ for(unsigned int i = 0; i < (*DetectPoints).size(); i++){ cv::circle(Img, (*DetectPoints)[i], 0.3, cv::Scalar(0, 0, 200)); } cv::imshow("result", Img); cv::waitKey(0); } #ifndef TEST int main() { cv::Mat Src= cv::imread("test.BMP",1); if(!Src.data){ printf("fail to open the image!\n"); return -1; } ExtractLines lines(Src); lines.imshow(); return 0; } #endif