opencv/samples/cpp/matchmethod_orb_akaze_brisk.cpp

#include <opencv2/opencv.hpp>
#include <vector>
#include <iostream>

using namespace std;
using namespace cv;

static void help()
{
    cout << "\n This program demonstrates how to detect compute and match ORB BRISK and AKAZE descriptors \n"
        "Usage: \n"
        "  ./matchmethod_orb_akaze_brisk <image1(../data/basketball1.png as default)> <image2(../data/basketball2.png as default)>\n"
        "Press a key when image window is active to change algorithm or descriptor";
}



int main(int argc, char *argv[])
{
    vector<String> typeDesc;
    vector<String> typeAlgoMatch;
    vector<String> fileName;
    help();
    // This descriptor are going to be detect and compute 
    typeDesc.push_back("AKAZE");    // see http://docs.opencv.org/trunk/d8/d30/classcv_1_1AKAZE.html
    typeDesc.push_back("ORB");      // see http://docs.opencv.org/trunk/de/dbf/classcv_1_1BRISK.html
    typeDesc.push_back("BRISK");    // see http://docs.opencv.org/trunk/db/d95/classcv_1_1ORB.html
   // This algorithm would be used to match descriptors see http://docs.opencv.org/trunk/db/d39/classcv_1_1DescriptorMatcher.html#ab5dc5036569ecc8d47565007fa518257
    typeAlgoMatch.push_back("BruteForce");
    typeAlgoMatch.push_back("BruteForce-L1");
    typeAlgoMatch.push_back("BruteForce-Hamming");
    typeAlgoMatch.push_back("BruteForce-Hamming(2)");
    if (argc==1)
    {
        fileName.push_back("../data/basketball1.png");
        fileName.push_back("../data/basketball2.png");
    }
    else if (argc==3)
    {
        fileName.push_back(argv[1]);
        fileName.push_back(argv[2]);
    }
    else
    {
        help();
        return(0);
    }
    Mat img1 = imread(fileName[0], IMREAD_GRAYSCALE);
    Mat img2 = imread(fileName[1], IMREAD_GRAYSCALE);
    if (img1.rows*img1.cols <= 0)
        {
        cout << "Image " << fileName[0] << " is empty or cannot be found\n";
        return(0);
        }
    if (img2.rows*img2.cols <= 0)
        {
        cout << "Image " << fileName[1] << " is empty or cannot be found\n";
        return(0);
        }

    vector<double> desMethCmp;
    Ptr<Feature2D> b;

    // Descriptor loop
    vector<String>::iterator itDesc;
    for (itDesc = typeDesc.begin(); itDesc != typeDesc.end(); itDesc++)
    {
        Ptr<DescriptorMatcher> descriptorMatcher;
        // Match between img1 and img2
        vector<DMatch> matches;	        
        // keypoint  for img1 and img2 
        vector<KeyPoint> keyImg1, keyImg2;
        // Descriptor for img1 and img2 
        Mat descImg1, descImg2;         
        vector<String>::iterator itMatcher = typeAlgoMatch.end();
        if (*itDesc == "AKAZE"){
            b = AKAZE::create();
        }
        if (*itDesc == "ORB"){
            b = ORB::create();
        }
        else if (*itDesc == "BRISK"){
            b = BRISK::create();
        }
        try {
            // We can detect keypoint with detect method
            b->detect(img1, keyImg1, Mat());
            // and compute their descriptors with method  compute
            b->compute(img1, keyImg1, descImg1);
            // or detect and compute descriptors in one step
            b->detectAndCompute(img2, Mat(),keyImg2, descImg2,false);
            // Match method loop
            for (itMatcher = typeAlgoMatch.begin(); itMatcher != typeAlgoMatch.end(); itMatcher++){
                descriptorMatcher = DescriptorMatcher::create(*itMatcher);
                descriptorMatcher->match(descImg1, descImg2, matches, Mat());
                // Keep best matches only to have a nice drawing.
                // We sort distance between descriptor matches
                Mat index;
                int nbMatch=int(matches.size());
                Mat tab(nbMatch, 1, CV_32F);
                for (int i = 0; i<nbMatch; i++)
                {
                    tab.at<float>(i, 0) = matches[i].distance;
                }
                sortIdx(tab, index, SORT_EVERY_COLUMN + SORT_ASCENDING);
                vector<DMatch> bestMatches;
                for (int i = 0; i<30; i++)
                {
                    bestMatches.push_back(matches[index.at<int>(i, 0)]);
                }
                Mat result;
                drawMatches(img1, keyImg1, img2, keyImg2, bestMatches, result);
                namedWindow(*itDesc+": "+*itMatcher, WINDOW_AUTOSIZE);
                imshow(*itDesc + ": " + *itMatcher, result);
                FileStorage fs(*itDesc+"_"+*itMatcher+"_"+fileName[0]+"_"+fileName[1]+".xml", FileStorage::WRITE);
                fs<<"Matches"<<matches;
                vector<DMatch>::iterator it;
                cout<<"**********Match results**********\n";
                cout << "Index \tIndex \tdistance\n";
                cout << "in img1\tin img2\n";
                double cumSumDist2=0; // Use to compute distance between keyPoint matches and to evaluate match algorithm
                for (it = bestMatches.begin(); it != bestMatches.end(); it++)
                {
                    cout << it->queryIdx << "\t" <<  it->trainIdx << "\t"  <<  it->distance << "\n";
                    Point2d p=keyImg1[it->queryIdx].pt-keyImg2[it->trainIdx].pt;
                    cumSumDist2=p.x*p.x+p.y*p.y;
                }
                desMethCmp.push_back(cumSumDist2);
                waitKey();
            }
        }
        catch (Exception& e)
        {
            cout << "Feature : " << *itDesc << "\n";
            if (itMatcher != typeAlgoMatch.end())
            {
                cout << "Matcher : " << *itMatcher << "\n";
            }
            cout<<e.msg<<endl;
        }
    }
    int i=0;
    cout << "Cumulative distance between keypoint match for different algorithm and feature detector \n\t";
    for (vector<String>::iterator itMatcher = typeAlgoMatch.begin(); itMatcher != typeAlgoMatch.end(); itMatcher++)
    {
        cout<<*itMatcher<<"\t";
    }
    cout << "\n";
    for (itDesc = typeDesc.begin(); itDesc != typeDesc.end(); itDesc++)
    {
        cout << *itDesc << "\t";
        for (vector<String>::iterator itMatcher = typeAlgoMatch.begin(); itMatcher != typeAlgoMatch.end(); itMatcher++, i++)
        {
            cout << desMethCmp[i]<<"\t";
        }
        cout<<"\n";
    }
    return 0;
}