摘要：
codebunny.ply/***@filetransformations.cpp*@briefVisualizingcloudindifferentpositions,coordinateframes,camerafrustums*@authorOzanCagriTonkal*/#include#include#include˂fstream
code
bunny.ply
/** * @file transformations.cpp * @brief Visualizing cloud in different positions, coordinate frames, camera frustums * @author Ozan Cagri Tonkal */#include <opencv2/viz.hpp>#include <iostream>#include <fstream> using namespace cv; using namespace std; /** * @function cvcloud_load * @brief load bunny.ply */static Mat cvcloud_load() { size_t num = 188; //1889. Mat cloud(1, num, CV_32FC3); ifstream ifs("../input/bunny.ply"); stringstr; for(size_t i = 0; i < 12; ++i) getline(ifs, str); Point3f* data = cloud.ptr<cv::Point3f>(); floatdummy1, dummy2; for(size_t i = 0; i < num; ++i) { ifs >> data[i].x >> data[i].y >> data[i].z >> dummy1 >>dummy2; std::cout << "i: " << i << "-x: " << data[i].x << "-y: " << data[i].y << "-z: " << data[i].z <<std::endl; } std::cout << "cloud: " << cloud <<std::endl; cloud *= 5.0f; std::cout << "cloud after: " << cloud <<std::endl; return cloud; } /** * @function main */ int main(int argn, char **argv) { //Create a window viz::Viz3d myWindow("Coordinate Frame"); //Create a cloud widget. Mat bunny_cloud =cvcloud_load(); viz::WCloud cloud_widget(bunny_cloud, viz::Color::green()); //Visualize widget myWindow.showWidget("bunny", cloud_widget); //Start event loop. myWindow.spin(); return 0; }
Remark1：
Mat cloud(1, num, CV_32FC3);
不知道为什么使用CV_64FC3不能正常显示，改为CV_32FC3即可，但是官方文档定义的数据格式中包含有
cloud- Set of points which can be of type: CV_32FC3, CV_32FC4, CV_64FC3, CV_64FC4Remark2：(filepath of bunny.ply after install opencv):
/opt/opencv-3.3.1/samples/cpp/tutorial_code/viz
CMakeLists.txt
cmake_minimum_required(VERSION 2.8) set(CMAKE_CXX_COMPILER "g++") set_property(GLOBAL PROPERTY USE_FOLDERS ON) list(APPEND CMAKE_CXX_FLAGS "-O3 -DEBUG -ffast-math -Wall -pthread -fopenmp -std=c++11") #-DNDEBUG project(test_viz3d) # OpenCV find_package(OpenCV 3.3.1REQUIRED) include_directories(${OpenCV_INCLUDE_DIRS}) message("OpenCV_INCLUDE_DIRS: ${OpenCV_INCLUDE_DIRS}") message("OpenCV_LIBS: ${OpenCV_LIBS}") # VTK find_package(VTK 5.10REQUIRED) include(${VTK_USE_FILE}) message("VTK_USE_FILE: ${VTK_USE_FILE}") message("VTK_LIBRARIES: ${VTK_LIBRARIES}") # PROJECT include_directories(include) aux_source_directory(src DIR_SRCS) add_executable(${PROJECT_NAME} ${DIR_SRCS}) target_link_libraries(${PROJECT_NAME} ${OpenCV_LIBS} ${VTK_LIBRARIES})
Remarks3：如何保存图像呢？
博主使用saveScreenshot可以保存截图，png格式可以正常显示图片，jpg格式不能；而且需要在显示的循环外层才可以使用，否则出错；
Segmentation fault (core dumped)
可以使用getScreenshot得到屏幕截图的Mat数据，但是感觉数据不完整；
cv::Mat shot = myWindow.getScreenshot();
std::cout << "shot: " << shot.type() << "size: " << shot.size() << std::endl;
Output:
shot: 16size: [960 x 540]
opencv官方文档中没有找到代码实例。
intmain() { double begin(0.0), end(0.0), cost(0.0); cv::viz::Viz3d window("Viz3D"); Mat bunny_cloud =cvcloud_load(); int cnt = 0; while(!window.wasStopped() && cnt<10) { cnt++; begin = (double)cv::getTickCount(); viz::WCloud cloud_widget(bunny_cloud, viz::Color::green()); window.showWidget("bunny", cloud_widget); end = (double)cv::getTickCount(); cost = (end-begin)*1000/cv::getTickFrequency(); std::cout << "showWidget cost(ms): " << cost <<std::endl; //cv::Mat shot = window.getScreenshot(); //std::cout << "shot: " << shot.type() << "size: " << shot.size() << std::endl; window.spinOnce(1, true); } window.saveScreenshot("Viz3D_bunny.png"); return 0; }
Remark4：耗时分析
准备数据的运行时间并不长，大概2/3ms左右，但是spin/spinOnce函数的调用耗时很久，大概要40/50ms左右，需要使用openGL实现3D绘图解决耗时较久的问题。
参考
3. Opencv_contrib_viz_sample_transformation;
完