OpenCV的GrabCut可运行代码及实例

本篇文章为大家展示了OpenCV的GrabCut可运行代码及实例，内容简明扼要并且容易理解，绝对能使你眼前一亮，通过这篇文章的详细介绍希望你能有所收获。

OpenCV中 GrabCut 的可运行代码

参考：http://www.cnblogs.com/tornadomeet/archive/2012/11/09/2763271.html

#include "opencv2/highgui/highgui.hpp"#include "opencv2/imgproc/imgproc.hpp"#include using namespace std;using namespace cv;static void help(){        cout << "\nThis program demonstrates GrabCut segmentation -- select an object in a region\n"                "and then grabcut will attempt to segment it out.\n"                "Call:\n"                "./grabcut \n"                "\nSelect a rectangular area around the object you want to segment\n" <<                "\nHot keys: \n"                "\tESC - quit the program\n"                "\tr - restore the original image\n"                "\tn - next iteration\n"                "\n"                "\tleft mouse button - set rectangle\n"                "\n"                "\tCTRL+left mouse button - set GC_BGD pixels\n"                "\tSHIFT+left mouse button - set CG_FGD pixels\n"                "\n"                "\tCTRL+right mouse button - set GC_PR_BGD pixels\n"                "\tSHIFT+right mouse button - set CG_PR_FGD pixels\n" << endl;}const Scalar RED = Scalar(0,0,255);const Scalar PINK = Scalar(230,130,255);const Scalar BLUE = Scalar(255,0,0);const Scalar LIGHTBLUE = Scalar(255,255,160);const Scalar GREEN = Scalar(0,255,0);const int BGD_KEY = CV_EVENT_FLAG_CTRLKEY;  //Ctrl键const int FGD_KEY = CV_EVENT_FLAG_SHIFTKEY; //Shift键static void getBinMask( const Mat& comMask, Mat& binMask ){        if( comMask.empty() || comMask.type()!=CV_8UC1 )                CV_Error( CV_StsBadArg, "comMask is empty or has incorrect type (not CV_8UC1)" );        if( binMask.empty() || binMask.rows!=comMask.rows || binMask.cols!=comMask.cols )                binMask.create( comMask.size(), CV_8UC1 );        binMask = comMask & 1;  //得到mask的最低位,实际上是只保留确定的或者有可能的前景点当做mask}class GCApplication{public:        enum{ NOT_SET = 0, IN_PROCESS = 1, SET = 2 };        static const int radius = 2;        static const int thickness = -1;        void reset();        void setImageAndWinName( const Mat& _image, const string& _winName );        void showImage() const;        void mouseClick( int event, int x, int y, int flags, void* param );        int nextIter();        int getIterCount() const { return iterCount; }private:        void setRectInMask();        void setLblsInMask( int flags, Point p, bool isPr );        const string* winName;        const Mat* image;        Mat mask;        Mat bgdModel, fgdModel;        uchar rectState, lblsState, prLblsState;        bool isInitialized;        Rect rect;        vector fgdPxls, bgdPxls, prFgdPxls, prBgdPxls;        int iterCount;};/*给类的变量赋值*/void GCApplication::reset(){        if( !mask.empty() )                mask.setTo(Scalar::all(GC_BGD));        bgdPxls.clear(); fgdPxls.clear();        prBgdPxls.clear();  prFgdPxls.clear();        isInitialized = false;        rectState = NOT_SET;    //NOT_SET == 0        lblsState = NOT_SET;        prLblsState = NOT_SET;        iterCount = 0;}/*给类的成员变量赋值而已*/void GCApplication::setImageAndWinName( const Mat& _image, const string& _winName  ){        if( _image.empty() || _winName.empty() )                return;        image = &_image;        winName = &_winName;        mask.create( image->size(), CV_8UC1);        reset();}/*显示4个点，一个矩形和图像内容，因为后面的步骤很多地方都要用到这个函数，所以单独拿出来*/void GCApplication::showImage() const{        if( image->empty() || winName->empty() )                return;        Mat res;        Mat binMask;        if( !isInitialized )                image->copyTo( res );        else        {                getBinMask( mask, binMask );                image->copyTo( res, binMask );  //按照最低位是0还是1来复制，只保留跟前景有关的图像，比如说可能的前景，可能的背景        }        vector::const_iterator it;        /*下面4句代码是将选中的4个点用不同的颜色显示出来*/        for( it = bgdPxls.begin(); it != bgdPxls.end(); ++it )  //迭代器可以看成是一个指针                circle( res, *it, radius, BLUE, thickness );        for( it = fgdPxls.begin(); it != fgdPxls.end(); ++it )  //确定的前景用红色表示                circle( res, *it, radius, RED, thickness );        for( it = prBgdPxls.begin(); it != prBgdPxls.end(); ++it )                circle( res, *it, radius, LIGHTBLUE, thickness );        for( it = prFgdPxls.begin(); it != prFgdPxls.end(); ++it )                circle( res, *it, radius, PINK, thickness );        /*画矩形*/        if( rectState == IN_PROCESS || rectState == SET )                rectangle( res, Point( rect.x, rect.y ), Point(rect.x + rect.width, rect.y + rect.height ), GREEN, 2);        imshow( *winName, res );}/*该步骤完成后，mask图像中rect内部是3，外面全是0*/void GCApplication::setRectInMask(){        assert( !mask.empty() );        mask.setTo( GC_BGD );   //GC_BGD == 0        rect.x = max(0, rect.x);        rect.y = max(0, rect.y);        rect.width = min(rect.width, image->cols-rect.x);        rect.height = min(rect.height, image->rows-rect.y);        (mask(rect)).setTo( Scalar(GC_PR_FGD) );    //GC_PR_FGD == 3，矩形内部,为可能的前景点}void GCApplication::setLblsInMask( int flags, Point p, bool isPr ){        vector *bpxls, *fpxls;        uchar bvalue, fvalue;        if( !isPr ) //确定的点        {                bpxls = &bgdPxls;                fpxls = &fgdPxls;                bvalue = GC_BGD;    //0                fvalue = GC_FGD;    //1        }        else    //概率点        {                bpxls = &prBgdPxls;                fpxls = &prFgdPxls;                bvalue = GC_PR_BGD; //2                fvalue = GC_PR_FGD; //3        }        if( flags & BGD_KEY )        {                bpxls->push_back(p);                circle( mask, p, radius, bvalue, thickness );   //该点处为2        }        if( flags & FGD_KEY )        {                fpxls->push_back(p);                circle( mask, p, radius, fvalue, thickness );   //该点处为3        }}/*鼠标响应函数，参数flags为CV_EVENT_FLAG的组合*/void GCApplication::mouseClick( int event, int x, int y, int flags, void* ){        // TODO add bad args check        switch( event )        {        case CV_EVENT_LBUTTONDOWN: // set rect or GC_BGD(GC_FGD) labels                {                        bool isb = (flags & BGD_KEY) != 0,                                isf = (flags & FGD_KEY) != 0;                        if( rectState == NOT_SET && !isb && !isf )//只有左键按下时                        {                                rectState = IN_PROCESS; //表示正在画矩形                                rect = Rect( x, y, 1, 1 );                        }                        if ( (isb || isf) && rectState == SET ) //按下了alt键或者shift键，且画好了矩形，表示正在画前景背景点                                lblsState = IN_PROCESS;                }                break;        case CV_EVENT_RBUTTONDOWN: // set GC_PR_BGD(GC_PR_FGD) labels                {                        bool isb = (flags & BGD_KEY) != 0,                                isf = (flags & FGD_KEY) != 0;                        if ( (isb || isf) && rectState == SET ) //正在画可能的前景背景点                                prLblsState = IN_PROCESS;                }                break;        case CV_EVENT_LBUTTONUP:                if( rectState == IN_PROCESS )                {                        rect = Rect( Point(rect.x, rect.y), Point(x,y) );   //矩形结束                        rectState = SET;                        setRectInMask();                        assert( bgdPxls.empty() && fgdPxls.empty() && prBgdPxls.empty() && prFgdPxls.empty() );                        showImage();                }                if( lblsState == IN_PROCESS )   //已画了前后景点                {                        setLblsInMask(flags, Point(x,y), false);    //画出前景点                        lblsState = SET;                        showImage();                }                break;        case CV_EVENT_RBUTTONUP:                if( prLblsState == IN_PROCESS )                {                        setLblsInMask(flags, Point(x,y), true); //画出背景点                        prLblsState = SET;                        showImage();                }                break;        case CV_EVENT_MOUSEMOVE:                if( rectState == IN_PROCESS )                {                        rect = Rect( Point(rect.x, rect.y), Point(x,y) );                        assert( bgdPxls.empty() && fgdPxls.empty() && prBgdPxls.empty() && prFgdPxls.empty() );                        showImage();    //不断的显示图片                }                else if( lblsState == IN_PROCESS )                {                        setLblsInMask(flags, Point(x,y), false);                        showImage();                }                else if( prLblsState == IN_PROCESS )                {                        setLblsInMask(flags, Point(x,y), true);                        showImage();                }                break;        }}/*该函数进行grabcut算法，并且返回算法运行迭代的次数*/int GCApplication::nextIter(){        if( isInitialized )                //使用grab算法进行一次迭代，参数2为mask，里面存的mask位是：矩形内部除掉那些可能是背景或者已经确定是背景后的所有的点，且mask同时也为输出                //保存的是分割后的前景图像                grabCut( *image, mask, rect, bgdModel, fgdModel, 1 );        else        {                if( rectState != SET )                        return iterCount;                if( lblsState == SET || prLblsState == SET )                        grabCut( *image, mask, rect, bgdModel, fgdModel, 1, GC_INIT_WITH_MASK );                else                        grabCut( *image, mask, rect, bgdModel, fgdModel, 1, GC_INIT_WITH_RECT );                isInitialized = true;        }        iterCount++;        bgdPxls.clear(); fgdPxls.clear();        prBgdPxls.clear(); prFgdPxls.clear();        return iterCount;}GCApplication gcapp;static void on_mouse( int event, int x, int y, int flags, void* param ){        gcapp.mouseClick( event, x, y, flags, param );}int main( int argc, char** argv ){        string filename = "C:\\Users\\ycadai\\Desktop\\9.jpg";        Mat image = imread( filename, 1 );        if( image.empty() )        {                cout << "\n Durn, couldn't read image filename " << filename << endl;                return 1;        }        help();        const string winName = "image";        cvNamedWindow( winName.c_str(), CV_WINDOW_AUTOSIZE );        cvSetMouseCallback( winName.c_str(), on_mouse, 0 );        gcapp.setImageAndWinName( image, winName );        gcapp.showImage();        for(;;)        {                int c = cvWaitKey(0);                switch( (char) c )                {                case '\x1b':                        cout << "Exiting ..." << endl;                        goto exit_main;                case 'r':                        cout << endl;                        gcapp.reset();                        gcapp.showImage();                        break;                case 'n':                        int iterCount = gcapp.getIterCount();                        cout << "<" << iterCount << "... ";                        int newIterCount = gcapp.nextIter();                        if( newIterCount > iterCount )                        {                                gcapp.showImage();                                cout << iterCount << ">" << endl;                        }                        else                                cout << "rect must be determined>" << endl;                        break;                }        }exit_main:        cvDestroyWindow( winName.c_str() );        return 0;}

真的很佩服这个算法！

运行结果：

A.

B.

C.

C例中的分割效果之好、迭代次数之少很让我惊讶。

D.

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