opencv2 学习第8天 提取分离前景和背景

GrabCut

代码来自于http://www.cnblogs.com/tornadomeet/archive/2012/11/09/2763271.html

#include <opencv2/highgui/highgui.hpp>#include <opencv2/core/core.hpp>#include <vector>#include <iostream>#include <opencv2/imgproc/imgproc.hpp>//#include "../../../../../Downloads/colourhistogram.h"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 <image_name>\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<Point> 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 == 0lblsState = 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<Point>::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 == 0rect.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<Point> *bpxls, *fpxls;uchar bvalue, fvalue;if( !isPr ) //确定的点{bpxls = &bgdPxls;fpxls = &fgdPxls;bvalue = GC_BGD;    //0fvalue = GC_FGD;    //1}else    //概率点{bpxls = &prBgdPxls;fpxls = &prFgdPxls;bvalue = GC_PR_BGD; //2fvalue = 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 checkswitch( 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 );elsegrabCut( *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 = "D:\\images\\dog.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;}elsecout << "rect must be determined>" << endl;break;}}exit_main:cvDestroyWindow( winName.c_str() );return 0;}

opencv2 书本上给的GrabCut的方法代码，实现起来速度也是不太能够忍受

class WatershedSegmenter {private:cv::Mat markers;public:void setMarkers(const cv::Mat& markerImage) {// Convert to image of intsmarkerImage.convertTo(markers,CV_32S);}cv::Mat process(const cv::Mat &image) {// Apply watershedcv::watershed(image,markers);return markers;}// Return result in the form of an imagecv::Mat getSegmentation() {cv::Mat tmp;// all segment with label higher than 255// will be assigned value 255markers.convertTo(tmp,CV_8U);return tmp;}// Return watershed in the form of an imagecv::Mat getWatersheds() {cv::Mat tmp;markers.convertTo(tmp,CV_8U,255,255);return tmp;}};int main(){using namespace cv;// Open another imageMat image= cv::imread("D:\\images\\tower.jpg");// define bounding rectanglecv::Rect rectangle(50,70,image.cols-150,image.rows-180);cv::Mat result; // segmentation result (4 possible values)cv::Mat bgModel,fgModel; // the models (internally used)// GrabCut segmentationcv::grabCut(image,    // input imageresult,   // segmentation resultrectangle,// rectangle containing foregroundbgModel,fgModel, // models1,        // number of iterationscv::GC_INIT_WITH_RECT); // use rectangle// Get the pixels marked as likely foregroundcv::compare(result,cv::GC_PR_FGD,result,cv::CMP_EQ);// Generate output imagecv::Mat foreground(image.size(),CV_8UC3,cv::Scalar(255,255,255));image.copyTo(foreground,result); // bg pixels not copied// draw rectangle on original imagecv::rectangle(image, rectangle, cv::Scalar(255,255,255),1);cv::namedWindow("Image");cv::imshow("Image",image);// display resultcv::namedWindow("Segmented Image");cv::imshow("Segmented Image",foreground);// Open another imageimage= cv::imread("D:\\images\\tower.jpg");// define bounding rectanglecv::Rect rectangle2(10,100,380,180);cv::Mat bkgModel,fgrModel; // the models (internally used)// GrabCut segmentationcv::grabCut(image,  // input imageresult, // segmentation resultrectangle2,bkgModel,fgrModel,5,cv::GC_INIT_WITH_RECT);// Get the pixels marked as likely foreground//      cv::compare(result,cv::GC_PR_FGD,result,cv::CMP_EQ);result= result&1;foreground.create(image.size(),CV_8UC3);foreground.setTo(cv::Scalar(255,255,255));image.copyTo(foreground,result); // bg pixels not copied// draw rectangle on original imagecv::rectangle(image, rectangle2, cv::Scalar(255,255,255),1);cv::namedWindow("Image 2");cv::imshow("Image 2",image);// display resultcv::namedWindow("Foreground objects");cv::imshow("Foreground objects",foreground);waitKey(0);system("pause");return 0;}