创建指定OpenCV版本的ROS工程

一、创建工作空间和程序包

mkdir -p ~/catkin_cv/src

cd catkin_cv/

catkin_make

source devel/setup.sh

cd src

catkin_create_pkg ballseeker roscpp rospy std_msgs sensor_msgs cv_bridge image_transport dynamic_reconfigure

二、创建并且编写cpp文件与hpp文件

gedit ballseeker/include/ballseeker/seek.hpp

gedit ballseeker/src/seek.cpp

gedit ballseeker/src/seekernode.cpp
#代码见附录

三、修改CMakeLists.txt

在CMakeLists最后加上：

# catkin_add_nosetests(test)
set(OpenCV_DIR   /usr/local/share/OpenCV4)
find_package(OpenCV REQUIRED)

add_library(${PROJECT_NAME}  src/seek.cpp)

add_dependencies(
   ${PROJECT_NAME} 
   ${${PROJECT_NAME}_EXPORTED_TARGETS} 
   ${catkin_EXPORTED_TARGETS}
)

target_link_libraries(
   ${PROJECT_NAME}
   ${catkin_LIBRARIES}
)

#add the publisher example  

add_executable(seekernode src/seek.cpp include/ballseeker/seek.hpp src/seekernode.cpp)  
target_link_libraries(seekernode ${catkin_LIBRARIES} ${OpenCV_LIBRARIES})   

四、编译与运行

cd catkin_cv/

source ~/catkin_cv/devel/setup.sh

catkin_make
#新开一个终端运行：
roscore
#再回之前的终端运行：
rosrun ballseeker seekernode

五、编写launch文件快速启动

在终端中运行：

cd ~/catkin_cv/src/ballseeker/launch

gedit quickstart.launch

在quickstart.launch中写入：

<launch>
    
    <node
pkg= "ballseeker"
name="quickseeknode" 
type="seekernode"
	/>

</launch>

回到终端再运行：

source ~/catkin_cv/devel/setup.sh

roslaunch ballseeker quickstart.launch

六、dynamic_reconfigure

略

七、调整与保存参数

略

八、附录（示例代码）

这里的代码的作用是调用摄像头来检测它看到的网球

在seek.hpp中写入：

#pragma once
#include "ros/ros.h"
#include "opencv2/opencv.hpp"
#include "vector"
#include "sstream"

const int red_ball = 0;
const int yellow_ball = 1;
const int blue_ball = 2;

class seek
{
public:
    seek(int service_id=0);
    ~seek();
    void getstart();        //从摄像头获取图片、双边滤波、转化hsv
    void display();         //找球并展示中间效果和最终效果
    void creatbar();        //创建滑动条调整参数

private:
    int bgr_min[3];
    int bgr_max[3];
    int hsv_min[3];
    int hsv_max[3];

    cv::Mat src;
    cv::Mat bgr_dst;
    cv::Mat hsv_dst;

    cv::Mat see_red;
    cv::Mat see_yellow;
    cv::Mat see_blue;

    cv::VideoCapture capture;
    void updateparam(int type_of_ball);
    void process(cv::Mat& input,int type_of_ball);//阈值化、膨胀、找轮廓、找矩形并筛选、画圆
    static void on_change(int, void*);
};

在seek.cpp中写入：

#include "../include/ballseeker/seek.hpp"

seek::seek(int service_id)
{
    //设置摄像机参数
    capture.open(1);
    capture.set(CV_CAP_PROP_FRAME_WIDTH,640);
	capture.set(CV_CAP_PROP_FRAME_HEIGHT,480);
}

seek::~seek()
{

}

void seek::getstart()
{
    capture>>src;
    cv::bilateralFilter(src,bgr_dst,20,1000,1000);
    cv::cvtColor(bgr_dst,hsv_dst,CV_BGR2HSV);
}

void seek::display()
{
    process(see_red,red_ball);       //可能得会用bgr处理红球了，HSV下效果不太好
    process(see_yellow,yellow_ball);
    process(see_blue,blue_ball);
    cv::imshow("SEE_RED_BALL",see_red);
    cv::imshow("SEE_YELLOW_BALL",see_yellow);
    cv::imshow("SEE_BLUE_BALL",see_blue);

    cv::imshow("FINALLY",src);

    cv::waitKey(30);
}

void seek::process(cv::Mat& input, int type_of_ball)
{
    updateparam(type_of_ball);

    cv::inRange(hsv_dst,cv::Scalar(hsv_min[0],hsv_min[1],hsv_min[2]),
        cv::Scalar(hsv_max[0],hsv_max[1],hsv_max[2]),input);

    cv::Mat element =cv::getStructuringElement(cv::MORPH_RECT, cv::Size(15, 15));   
    cv::dilate(input, input, element);

    std::vector<std::vector<cv::Point> > contours;
    std::vector<cv::Vec4i> hierarchy;
    std::vector<cv::Rect> rects;

    cv::findContours(input, contours, hierarchy, cv::RETR_CCOMP, cv::CHAIN_APPROX_SIMPLE);

    for (int i = 0; i < contours.size(); i++)
    {
        rects.push_back(cv::boundingRect(contours[i]));
        if ((rects.back().height < 100 || rects.back().width < 100) ||
            fabsf(rects.back().height - rects.back().width) > 20)
            rects.erase(rects.end() - 1);
    }

    for (int i = 0; i < rects.size(); i++)
    {
        double R = (rects[i].height + rects[i].width) / 4;
        double x = rects[i].x + R;
        double y = rects[i].y + R;
        cv::Point center(x, y);
        cv::circle(src, center, R + 5, cv::Scalar(0, 0, 255), 5);
    }
}

void seek::updateparam(int type_of_ball)
{
    switch (type_of_ball)
    {
    case red_ball:
        hsv_min[0]= 0 ;hsv_min[1]= 105 ;hsv_min[2]= 108 ;
        hsv_max[0]= 11 ;hsv_max[1]= 255 ;hsv_max[1]= 255 ;
        break;
    case yellow_ball:
        hsv_min[0]= 18 ;hsv_min[1]= 56 ;hsv_min[2]= 177 ;
        hsv_max[0]= 71 ;hsv_max[1]= 187 ;hsv_max[1]= 255 ;
        break;
    case blue_ball:
        hsv_min[0]= 85 ;hsv_min[1]= 129 ;hsv_min[2]= 128 ;
        hsv_max[0]= 124 ;hsv_max[1]= 255 ;hsv_max[1]= 255 ;
        break;
    default:
        break;
    }
}

void seek::creatbar()
{
    cv::namedWindow("SetParam");
	cv::createTrackbar("minH", "SetParam", &hsv_min[0], 180, on_change);
	cv::createTrackbar("minS", "SetParam", &hsv_min[1], 255, on_change);
	cv::createTrackbar("minV", "SetParam", &hsv_min[2], 255, on_change);
	cv::createTrackbar("maxH", "SetParam", &hsv_max[0], 180, on_change);
	cv::createTrackbar("maxS", "SetParam", &hsv_max[1], 255, on_change);
	cv::createTrackbar("maxV", "SetParam", &hsv_max[2], 255, on_change);
	on_change(0, 0);
}

void seek::on_change(int, void*)
{

}

在seekernode.cpp中写入：

#include "../include/ballseeker/seek.hpp"


int main(int argc,char** argv)
{
    ros::init(argc,argv,"seekernode");
    ros::NodeHandle n;

    seek icu(1);
    icu.creatbar();

    while(ros::ok())
    {
        icu.getstart();
        icu.display();
        ros::spinOnce();
    }

    return 0;
}