OpenCV学习笔记（11）：hough变换和概率hough变换

#include "stdafx.h"#include "opencv2/highgui/highgui.hpp"#include "opencv2/imgproc/imgproc.hpp"#include <iostream>#include <stdio.h>using namespace cv;using namespace std;/// Global variables/** General variables */Mat src, edges;Mat src_gray;Mat standard_hough, probabilistic_hough;int min_threshold = 50;int max_trackbar = 150;const char* standard_name = "Standard Hough Lines Demo";const char* probabilistic_name = "Probabilistic Hough Lines Demo";int s_trackbar = max_trackbar;int p_trackbar = max_trackbar;/// Function Headersvoid help();void Standard_Hough(int, void*);void Probabilistic_Hough(int, void*);int main(int, char** argv){/// Read the imagesrc = imread("lena.png", 1);if (src.empty()){help();return -1;}/// Pass the image to graycvtColor(src, src_gray, COLOR_RGB2GRAY);/// Apply Canny edge detectorCanny(src_gray, edges, 50, 200, 3);/// Create Trackbars for Thresholdschar thresh_label[50];sprintf_s(thresh_label, "Thres: %d + input", min_threshold);namedWindow(standard_name, WINDOW_AUTOSIZE);createTrackbar(thresh_label, standard_name, &s_trackbar, max_trackbar, Standard_Hough);namedWindow(probabilistic_name, WINDOW_AUTOSIZE);createTrackbar(thresh_label, probabilistic_name, &p_trackbar, max_trackbar, Probabilistic_Hough);/// InitializeStandard_Hough(0, 0);Probabilistic_Hough(0, 0);waitKey(0);return 0;}void help(){printf("\t Hough Transform to detect lines \n ");printf("\t---------------------------------\n ");printf(" Usage: ./HoughLines_Demo <image_name> \n");}/*** @function Standard_Hough*/void Standard_Hough(int, void*){vector<Vec2f> s_lines;cvtColor(edges, standard_hough, CV_GRAY2BGR);/// 1. Use Standard Hough TransformHoughLines(edges, s_lines, 1, CV_PI / 180, min_threshold + s_trackbar, 0, 0);/// Show the resultfor (size_t i = 0; i < s_lines.size(); i++){float r = s_lines[i][0], t = s_lines[i][1];double cos_t = cos(t), sin_t = sin(t);double x0 = r*cos_t, y0 = r*sin_t;double alpha = 1000;Point pt1(cvRound(x0 + alpha*(-sin_t)), cvRound(y0 + alpha*cos_t));Point pt2(cvRound(x0 - alpha*(-sin_t)), cvRound(y0 - alpha*cos_t));line(standard_hough, pt1, pt2, Scalar(255, 0, 0), 3, CV_AA);}imshow(standard_name, standard_hough);}/*** @function Probabilistic_Hough*/void Probabilistic_Hough(int, void*){vector<Vec4i> p_lines;cvtColor(edges, probabilistic_hough, CV_GRAY2BGR);/// 2. Use Probabilistic Hough TransformHoughLinesP(edges, p_lines, 1, CV_PI / 180, min_threshold + p_trackbar, 30, 10);/// Show the resultfor (size_t i = 0; i < p_lines.size(); i++){Vec4i l = p_lines[i];line(probabilistic_hough, Point(l[0], l[1]), Point(l[2], l[3]), Scalar(255, 0, 0), 3, CV_AA);}imshow(probabilistic_name, probabilistic_hough);}