opencv 6 图像轮廓与图像分割修复 3 图像的矩

图像的矩

矩的计算：moments()函数

计算轮廓面积：contourArea()函数

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include<iostream>
using namespace cv;
using namespace std;



//-----------------------------------【main( )函数】--------------------------------------------
//   描述：控制台应用程序的入口函数，我们的程序从这里开始执行
//-----------------------------------------------------------------------------------------------
int main()
{
    vector<Point> contour;
    contour.push_back(Point2f(0, 0));
    contour.push_back(Point2f(10, 0));
    contour.push_back(Point2f(10, 10));
    contour.push_back(Point2f(5, 4));
     
    double area0 = contourArea(contour);
    vector<Point> approx;
    approxPolyDP(contour, approx, 5, true);
    double area1 = contourArea(approx);

    cout << "area0=" << area0 << endl << "area1=" << area1 << endl << "approx poly vertices=" << approx.size() << endl;
    waitKey(0);
    system("pause");
    return(0);
}

计算轮廓长度：arcLength()函数

综合实例程序：查找和绘制图像轮廓矩

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
using namespace cv;
using namespace std;


//-----------------------------------【宏定义部分】-------------------------------------------- 
//      描述：定义一些辅助宏 
//------------------------------------------------------------------------------------------------ 
#define WINDOW_NAME1 "【原始图】"                    //为窗口标题定义的宏 
#define WINDOW_NAME2 "【图像轮廓】"        //为窗口标题定义的宏 


//-----------------------------------【全局变量声明部分】--------------------------------------
//      描述：全局变量的声明
//-----------------------------------------------------------------------------------------------
Mat g_srcImage; Mat g_grayImage;
int g_nThresh = 100;
int g_nMaxThresh = 255;
RNG g_rng(12345);
Mat g_cannyMat_output;
vector<vector<Point> > g_vContours;
vector<Vec4i> g_vHierarchy;

//-----------------------------------【全局变量声明部分】--------------------------------------
//      描述：全局变量的声明
//-----------------------------------------------------------------------------------------------
void on_ThreshChange(int, void*);
static void ShowHelpText();

//-----------------------------------【main( )函数】--------------------------------------------
//      描述：控制台应用程序的入口函数，我们的程序从这里开始执行
//-----------------------------------------------------------------------------------------------
int main(int argc, char** argv)
{
    //【0】改变console字体颜色
    system("color 9F");

    ShowHelpText();
    // 读入原图像, 返回3通道图像数据
    g_srcImage = imread("1.jpg", 1);

    // 把原图像转化成灰度图像并进行平滑
    cvtColor(g_srcImage, g_grayImage, COLOR_BGR2GRAY);
    blur(g_grayImage, g_grayImage, Size(3, 3));

    // 创建新窗口
    namedWindow(WINDOW_NAME1, WINDOW_AUTOSIZE);
    imshow(WINDOW_NAME1, g_srcImage);

    //创建滚动条并进行初始化
    createTrackbar(" 阈值", WINDOW_NAME1, &g_nThresh, g_nMaxThresh, on_ThreshChange);
    on_ThreshChange(0, 0);

    waitKey(0);
    return(0);
}

//-----------------------------------【on_ThreshChange( )函数】-------------------------------
//      描述：回调函数
//-----------------------------------------------------------------------------------------------
void on_ThreshChange(int, void*)
{
    // 使用Canndy检测边缘
    Canny(g_grayImage, g_cannyMat_output, g_nThresh, g_nThresh * 2, 3);

    // 找到轮廓
    findContours(g_cannyMat_output, g_vContours, g_vHierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE, Point(0, 0));

    // 计算矩
    vector<Moments> mu(g_vContours.size());
    for (unsigned int i = 0; i < g_vContours.size(); i++)
    {
        mu[i] = moments(g_vContours[i], false);
    }

    //  计算中心矩
    vector<Point2f> mc(g_vContours.size());
    for (unsigned int i = 0; i < g_vContours.size(); i++)
    {
        mc[i] = Point2f(static_cast<float>(mu[i].m10 / mu[i].m00), static_cast<float>(mu[i].m01 / mu[i].m00));
    }

    // 绘制轮廓
    Mat drawing = Mat::zeros(g_cannyMat_output.size(), CV_8UC3);
    for (unsigned int i = 0; i < g_vContours.size(); i++)
    {
        Scalar color = Scalar(g_rng.uniform(0, 255), g_rng.uniform(0, 255), g_rng.uniform(0, 255));//随机生成颜色值
        drawContours(drawing, g_vContours, i, color, 2, 8, g_vHierarchy, 0, Point());//绘制外层和内层轮廓
        circle(drawing, mc[i], 4, color, -1, 8, 0);;//绘制圆
    }

    // 显示到窗口中
    namedWindow(WINDOW_NAME2, WINDOW_AUTOSIZE);
    imshow(WINDOW_NAME2, drawing);

    // 通过m00计算轮廓面积并且和OpenCV函数比较
    printf("\t 输出内容: 面积和轮廓长度\n");
    for (unsigned int i = 0; i < g_vContours.size(); i++)
    {
        printf(" >通过m00计算出轮廓[%d]的面积: (M_00) = %.2f \n OpenCV函数计算出的面积=%.2f , 长度: %.2f \n\n", i, mu[i].m00, contourArea(g_vContours[i]), arcLength(g_vContours[i], true));
        Scalar color = Scalar(g_rng.uniform(0, 255), g_rng.uniform(0, 255), g_rng.uniform(0, 255));
        drawContours(drawing, g_vContours, i, color, 2, 8, g_vHierarchy, 0, Point());
        circle(drawing, mc[i], 4, color, -1, 8, 0);
    }
}


//-----------------------------------【ShowHelpText( )函数】-----------------------------
//       描述：输出一些帮助信息
//----------------------------------------------------------------------------------------------
void ShowHelpText()
{
    //输出欢迎信息和OpenCV版本
    printf("\n\n\t\t\t   当前使用的OpenCV版本为：" CV_VERSION);
    printf("\n\n  ----------------------------------------------------------------------------\n");
}

分水岭算法

实现分水岭算法：watershed()函数

综合示例程序：分水岭算法

#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <iostream>
using namespace cv;
using namespace std;

//-----------------------------------【宏定义部分】-------------------------------------------- 
//  描述：定义一些辅助宏 
//------------------------------------------------------------------------------------------------ 
#define WINDOW_NAME1 "【程序窗口1】"        //为窗口标题定义的宏 
#define WINDOW_NAME2 "【分水岭算法效果图】"        //为窗口标题定义的宏

//-----------------------------------【全局函变量声明部分】--------------------------------------
//      描述：全局变量的声明
//-----------------------------------------------------------------------------------------------
Mat g_maskImage, g_srcImage;
Point prevPt(-1, -1);

//-----------------------------------【全局函数声明部分】--------------------------------------
//      描述：全局函数的声明
//-----------------------------------------------------------------------------------------------
static void ShowHelpText();
static void on_Mouse(int event, int x, int y, int flags, void*);


//-----------------------------------【main( )函数】--------------------------------------------
//      描述：控制台应用程序的入口函数，我们的程序从这里开始执行
//-----------------------------------------------------------------------------------------------
int main(int argc, char** argv)
{
    //【0】改变console字体颜色
    system("color 6F");

    //【0】显示帮助文字
    ShowHelpText();

    //【1】载入原图并显示，初始化掩膜和灰度图
    g_srcImage = imread("1.jpg", 1);
    imshow(WINDOW_NAME1, g_srcImage);
    Mat srcImage, grayImage;
    g_srcImage.copyTo(srcImage);
    cvtColor(g_srcImage, g_maskImage, COLOR_BGR2GRAY);
    cvtColor(g_maskImage, grayImage, COLOR_GRAY2BGR);
    g_maskImage = Scalar::all(0);

    //【2】设置鼠标回调函数
    setMouseCallback(WINDOW_NAME1, on_Mouse, 0);

    //【3】轮询按键，进行处理
    while (1)
    {
        //获取键值
        int c = waitKey(0);

        //若按键键值为ESC时，退出
        if ((char)c == 27)
            break;

        //按键键值为2时，恢复源图
        if ((char)c == '2')
        {
            g_maskImage = Scalar::all(0);
            srcImage.copyTo(g_srcImage);
            imshow("image", g_srcImage);
        }

        //若检测到按键值为1或者空格，则进行处理
        if ((char)c == '1' || (char)c == ' ')
        {
            //定义一些参数
            int i, j, compCount = 0;
            vector<vector<Point> > contours;
            vector<Vec4i> hierarchy;

            //寻找轮廓
            findContours(g_maskImage, contours, hierarchy, RETR_CCOMP, CHAIN_APPROX_SIMPLE);

            //轮廓为空时的处理
            if (contours.empty())
                continue;

            //拷贝掩膜
            Mat maskImage(g_maskImage.size(), CV_32S);
            maskImage = Scalar::all(0);

            //循环绘制出轮廓
            for (int index = 0; index >= 0; index = hierarchy[index][0], compCount++)
                drawContours(maskImage, contours, index, Scalar::all(compCount + 1), -1, 8, hierarchy, INT_MAX);

            //compCount为零时的处理
            if (compCount == 0)
                continue;

            //生成随机颜色
            vector<Vec3b> colorTab;
            for (i = 0; i < compCount; i++)
            {
                int b = theRNG().uniform(0, 255);
                int g = theRNG().uniform(0, 255);
                int r = theRNG().uniform(0, 255);

                colorTab.push_back(Vec3b((uchar)b, (uchar)g, (uchar)r));
            }

            //计算处理时间并输出到窗口中
            double dTime = (double)getTickCount();
            watershed(srcImage, maskImage);
            dTime = (double)getTickCount() - dTime;
            printf("\t处理时间 = %gms\n", dTime*1000. / getTickFrequency());

            //双层循环，将分水岭图像遍历存入watershedImage中
            Mat watershedImage(maskImage.size(), CV_8UC3);
            for (i = 0; i < maskImage.rows; i++)
                for (j = 0; j < maskImage.cols; j++)
                {
                    int index = maskImage.at<int>(i, j);
                    if (index == -1)
                        watershedImage.at<Vec3b>(i, j) = Vec3b(255, 255, 255);
                    else if (index <= 0 || index > compCount)
                        watershedImage.at<Vec3b>(i, j) = Vec3b(0, 0, 0);
                    else
                        watershedImage.at<Vec3b>(i, j) = colorTab[index - 1];
                }

            //混合灰度图和分水岭效果图并显示最终的窗口
            watershedImage = watershedImage * 0.5 + grayImage * 0.5;
            imshow(WINDOW_NAME2, watershedImage);
        }
    }

    return 0;
}


//-----------------------------------【onMouse( )函数】---------------------------------------
//      描述：鼠标消息回调函数
//-----------------------------------------------------------------------------------------------
static void on_Mouse(int event, int x, int y, int flags, void*)
{
    //处理鼠标不在窗口中的情况
    if (x < 0 || x >= g_srcImage.cols || y < 0 || y >= g_srcImage.rows)
        return;

    //处理鼠标左键相关消息
    if (event == EVENT_LBUTTONUP || !(flags & EVENT_FLAG_LBUTTON))
        prevPt = Point(-1, -1);
    else if (event == EVENT_LBUTTONDOWN)
        prevPt = Point(x, y);

    //鼠标左键按下并移动，绘制出白色线条
    else if (event == EVENT_MOUSEMOVE && (flags & EVENT_FLAG_LBUTTON))
    {
        Point pt(x, y);
        if (prevPt.x < 0)
            prevPt = pt;
        line(g_maskImage, prevPt, pt, Scalar::all(255), 5, 8, 0);
        line(g_srcImage, prevPt, pt, Scalar::all(255), 5, 8, 0);
        prevPt = pt;
        imshow(WINDOW_NAME1, g_srcImage);
    }
}


//-----------------------------------【ShowHelpText( )函数】----------------------------------  
//      描述：输出一些帮助信息  
//----------------------------------------------------------------------------------------------  
static void ShowHelpText()
{
    //输出欢迎信息和OpenCV版本
    printf("\n\n\t\t\t   当前使用的OpenCV版本为：" CV_VERSION);
    printf("\n\n  ----------------------------------------------------------------------------\n");

    //输出一些帮助信息  
    printf("\n\n\n\t欢迎来到【分水岭算法】示例程序~\n\n");
    printf("\t请先用鼠标在图片窗口中标记出大致的区域，\n\n\t然后再按键【1】或者【SPACE】启动算法。"
        "\n\n\t按键操作说明: \n\n"
        "\t\t键盘按键【1】或者【SPACE】- 运行的分水岭分割算法\n"
        "\t\t键盘按键【2】- 恢复原始图片\n"
        "\t\t键盘按键【ESC】- 退出程序\n\n\n");
}

图像修补