OpenCV3.2 單目攝像頭的標定與矯正[轉]
阿新 • • 發佈:2019-01-06
/*------------------------------------------------------------------------------------------*\ This file contains material supporting chapter 11 of the book: OpenCV3 Computer Vision Application Programming Cookbook Third Edition by Robert Laganiere, Packt Publishing, 2016. This program is free software; permission is hereby granted to use, copy, modify, and distribute this source code, or portions thereof, for any purpose, without fee, subject to the restriction that the copyright notice may not be removed or altered from any source or altered source distribution. The software is released on an as-is basis and without any warranties of any kind. In particular, the software is not guaranteed to be fault-tolerant or free from failure. The author disclaims all warranties with regard to this software, any use, and any consequent failure, is purely the responsibility of the user. Copyright (C) 2016 Robert Laganiere, www.laganiere.name \*------------------------------------------------------------------------------------------*/ #ifndef CAMERACALIBRATOR_H #define CAMERACALIBRATOR_H #include <vector> #include <iostream> #include <opencv2/core.hpp> #include "opencv2/imgproc.hpp" #include "opencv2/calib3d.hpp" #include <opencv2/highgui.hpp> class CameraCalibrator { // input points: // the points in world coordinates // (each square is one unit) std::vector<std::vector<cv::Point3f> > objectPoints; // the image point positions in pixels std::vector<std::vector<cv::Point2f> > imagePoints; // output Matrices cv::Mat cameraMatrix; cv::Mat distCoeffs; // flag to specify how calibration is done int flag; // used in image undistortion cv::Mat map1,map2; bool mustInitUndistort; public: CameraCalibrator() : flag(0), mustInitUndistort(true) {} // Open the chessboard images and extract corner points int addChessboardPoints(const std::vector<std::string>& filelist, cv::Size & boardSize, std::string windowName=""); // Add scene points and corresponding image points void addPoints(const std::vector<cv::Point2f>& imageCorners, const std::vector<cv::Point3f>& objectCorners); // Calibrate the camera double calibrate(const cv::Size imageSize); // Set the calibration flag void setCalibrationFlag(bool radial8CoeffEnabled=false, bool tangentialParamEnabled=false); // Remove distortion in an image (after calibration) cv::Mat remap(const cv::Mat &image, cv::Size &outputSize ); // Getters cv::Mat getCameraMatrix() { return cameraMatrix; } cv::Mat getDistCoeffs() { return distCoeffs; } }; #endif // CAMERACALIBRATOR_H
/*------------------------------------------------------------------------------------------*\ This file contains material supporting chapter 11 of the book: OpenCV3 Computer Vision Application Programming Cookbook Third Edition by Robert Laganiere, Packt Publishing, 2016. This program is free software; permission is hereby granted to use, copy, modify, and distribute this source code, or portions thereof, for any purpose, without fee, subject to the restriction that the copyright notice may not be removed or altered from any source or altered source distribution. The software is released on an as-is basis and without any warranties of any kind. In particular, the software is not guaranteed to be fault-tolerant or free from failure. The author disclaims all warranties with regard to this software, any use, and any consequent failure, is purely the responsibility of the user. Copyright (C) 2016 Robert Laganiere, www.laganiere.name \*------------------------------------------------------------------------------------------*/ #include "CameraCalibrator.h" // Open chessboard images and extract corner points int CameraCalibrator::addChessboardPoints( const std::vector<std::string>& filelist, // list of filenames containing board images cv::Size & boardSize, // size of the board std::string windowName) { // name of window to display results // if null, no display shown // the points on the chessboard std::vector<cv::Point2f> imageCorners; std::vector<cv::Point3f> objectCorners; // 3D Scene Points: // Initialize the chessboard corners // in the chessboard reference frame // The corners are at 3D location (X,Y,Z)= (i,j,0) for (int i=0; i<boardSize.height; i++) { for (int j=0; j<boardSize.width; j++) { objectCorners.push_back(cv::Point3f(i, j, 0.0f)); } } // 2D Image points: cv::Mat image; // to contain chessboard image int successes = 0; // for all viewpoints for (int i=0; i<filelist.size(); i++) { // Open the image image = cv::imread(filelist[i],0); // Get the chessboard corners bool found = cv::findChessboardCorners(image, // image of chessboard pattern boardSize, // size of pattern imageCorners); // list of detected corners // Get subpixel accuracy on the corners if (found) { cv::cornerSubPix(image, imageCorners, cv::Size(5, 5), // half size of serach window cv::Size(-1, -1), cv::TermCriteria(cv::TermCriteria::MAX_ITER + cv::TermCriteria::EPS, 30, // max number of iterations 0.1)); // min accuracy // If we have a good board, add it to our data if (imageCorners.size() == boardSize.area()) { // Add image and scene points from one view addPoints(imageCorners, objectCorners); successes++; } } if (windowName.length()>0 && imageCorners.size() == boardSize.area()) { //Draw the corners cv::drawChessboardCorners(image, boardSize, imageCorners, found); cv::imshow(windowName, image); cv::waitKey(500); } } return successes; } // Add scene points and corresponding image points void CameraCalibrator::addPoints(const std::vector<cv::Point2f>& imageCorners, const std::vector<cv::Point3f>& objectCorners) { // 2D image points from one view imagePoints.push_back(imageCorners); // corresponding 3D scene points objectPoints.push_back(objectCorners); } // Calibrate the camera // returns the re-projection error double CameraCalibrator::calibrate(const cv::Size imageSize) { // undistorter must be reinitialized mustInitUndistort= true; //Output rotations and translations std::vector<cv::Mat> rvecs, tvecs; // start calibration return cv::calibrateCamera(objectPoints, // the 3D points imagePoints, // the image points imageSize, // image size cameraMatrix, // output camera matrix distCoeffs, // output distortion matrix rvecs, tvecs, // Rs, Ts CV_CALIB_USE_INTRINSIC_GUESS ); // set options // ,CV_CALIB_USE_INTRINSIC_GUESS); } // remove distortion in an image (after calibration) cv::Mat CameraCalibrator::remap(const cv::Mat &image, cv::Size &outputSize) { cv::Mat undistorted; if (outputSize.height == -1) outputSize = image.size(); if (mustInitUndistort) { // called once per calibration // cv::Mat dist = (cv::Mat_<double>(1, 14) << -107.8067046233813, 3606.394522865697, -0.003208480233032964, 0.00212257161649465, -706.3301131023582, -107.3590793091425, 3559.830030448713, 855.5629043718579, 0, 0, 0, 0, 0, 0); // dist = distCoeffs; cv::initUndistortRectifyMap( cameraMatrix, // computed camera matrix distCoeffs, // computed distortion matrix cv::Mat(), // optional rectification (none) cv::Mat(), // camera matrix to generate undistorted outputSize, // size of undistorted CV_32FC1, // type of output map map1, map2); // the x and y mapping functions mustInitUndistort= false; } // Apply mapping functions cv::remap(image, undistorted, map1, map2, cv::INTER_LINEAR); // interpolation type return undistorted; } // Set the calibration options // 8radialCoeffEnabled should be true if 8 radial coefficients are required (5 is default) // tangentialParamEnabled should be true if tangeantial distortion is present void CameraCalibrator::setCalibrationFlag(bool radial8CoeffEnabled, bool tangentialParamEnabled) { // Set the flag used in cv::calibrateCamera() flag = 0; if (!tangentialParamEnabled) flag += CV_CALIB_ZERO_TANGENT_DIST; if (radial8CoeffEnabled) flag += CV_CALIB_RATIONAL_MODEL; }
#include <iostream> #include <iomanip> #include <vector> #include <opencv2/core.hpp> #include <opencv2/imgproc.hpp> #include <opencv2/highgui.hpp> #include <opencv2/features2d.hpp> #include "CameraCalibrator.h" #define PATH "F:/QtProjects/stero/stereo4/right" #define PICS_NUM 17 int main() { cv::Mat image; std::vector<std::string> filelist; // generate list of chessboard image filename // named chessboard01 to chessboard27 in chessboard sub-dir for (int i=1; i<=PICS_NUM; i++) { std::stringstream str; str << PATH << std::setw(2) << std::setfill('0') << i << ".png"; std::cout << str.str() << std::endl; filelist.push_back(str.str()); image= cv::imread(str.str(),0); // cv::imshow("Board Image",image); // cv::waitKey(500); } // Create calibrator object CameraCalibrator cameraCalibrator; // add the corners from the chessboard cv::Size boardSize(8,6); cameraCalibrator.addChessboardPoints( filelist, // filenames of chessboard image boardSize, "Detected points"); // size of chessboard // calibrate the camera cameraCalibrator.setCalibrationFlag(true,true); cameraCalibrator.calibrate(image.size()); // Exampple of Image Undistortion std::cout << filelist[5] << std::endl; image = cv::imread(filelist[5],0); cv::Size newSize(static_cast<int>(image.cols*1.5), static_cast<int>(image.rows*1.5)); cv::Mat uImage= cameraCalibrator.remap(image, newSize); // display camera matrix cv::Mat cameraMatrix= cameraCalibrator.getCameraMatrix(); cv::Mat distCoeffs=cameraCalibrator.getDistCoeffs(); std::cout << " Camera intrinsic: " << cameraMatrix.rows << "x" << cameraMatrix.cols << std::endl; std::cout << cameraMatrix.at<double>(0,0) << " " << cameraMatrix.at<double>(0,1) << " " << cameraMatrix.at<double>(0,2) << std::endl; std::cout << cameraMatrix.at<double>(1,0) << " " << cameraMatrix.at<double>(1,1) << " " << cameraMatrix.at<double>(1,2) << std::endl; std::cout << cameraMatrix.at<double>(2,0) << " " << cameraMatrix.at<double>(2,1) << " " << cameraMatrix.at<double>(2,2) << std::endl; std::cout << distCoeffs.rows << "x" <<distCoeffs.cols << std::endl; std::cout << distCoeffs << std::endl; for(int i = 0;i < distCoeffs.cols;i++) { std::cout << distCoeffs.at<double>(0,i) << " " ; } std::cout <<std::endl; cv::namedWindow("Original Image"); cv::imshow("Original Image", image); cv::namedWindow("Undistorted Image"); cv::imshow("Undistorted Image", uImage); // Store everything in a xml file cv::FileStorage fs("calib.xml", cv::FileStorage::WRITE); fs << "Intrinsic" << cameraMatrix; fs << "Distortion" << cameraCalibrator.getDistCoeffs(); cv::waitKey(); return 0; }
經驗總結
- 照片要不同角度和距離拍攝,最好15張以上,不要偷懶。
- 出現矯正效果不好的情況,可以改變一下函式calibrateCamera中的引數flag。使用CV_CALIB_FIX_K3可以使畸變矩陣輸出四個引數。根據網上部落格的經驗對於低端攝像頭來說需要的引數數量一般使用5個或者4個比較合適。
From:OpenCV3.2 單目攝像頭的標定與矯正 作者:Jacob楊幫幫