Чтение нарушения прав доступа в FeatureDetector OpenCV 2.4.5

Я попробовал примеры кода для сопоставления со многими изображениями в OpenCV 2.4.5 и изменил этот код. Я нашел код ошибки:

Unhandled exception at 0x585a7090 in testing.exe:
0xC0000005: Access violation reading location 0x00000000.

Его ошибка в featureDetector->detect(queryImage, queryKeypoints).

Я не могу найти решение этой проблемы. Помогите пожалуйста мне.

#include <opencv2\highgui\highgui.hpp>
#include <opencv2\features2d\features2d.hpp>
#include <opencv2\contrib\contrib.hpp>
#include <iostream>
#include <fstream>
#include <conio.h>
#include <string>

using namespace std;
using namespace cv;

static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames);
static bool readImages(const string& queryImageName,  Mat& queryImage);
static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames);
static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints,
    const vector<Mat>& trainImages, vector<vector<KeyPoint>>& trainKeypoints, Ptr<FeatureDetector>& featureDetector);


static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames)
{
    trainFilenames.clear();

    ifstream file(filename.c_str());

    if(!file.is_open())
    {
        cout << "File can't open" << endl;
        return;
    }

    size_t pos = filename.rfind("\\");
    char dlmtr = '\\';

    if(pos == String::npos)
    {
        pos = filename.rfind('/');
        dlmtr = '/';
    }

    dirName = pos == string::npos ? "" : filename.substr(0, pos) + dlmtr;

    while(!file.eof())
    {
        string str; getline(file, str);
        if(str.empty()) break;
        trainFilenames.push_back(str);
    } // end while

    file.close();
} // end void readTrainFilenames


static bool readImages(const string& queryImageName,  Mat& queryImage)
{
    cout << "reading  images..." << endl;
    queryImage = imread(queryImageName, CV_LOAD_IMAGE_GRAYSCALE);
    if(queryImage.empty())
    {
        cout << "query image can not be read. \n";
        return false;
    } // end if


    return true;
}

static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames)
{
    cout << "reading training images..." << endl;
    string trainDirName = "D:/matching_to_many_images/";

    readTrainFilenames(trainFilename, trainDirName, trainImageNames);
    if(trainImageNames.empty())
    {
        cout << "Train image filenames can not be read." << endl;
        return false;
    } // end if

    int readImageCount = 0;
    for(size_t i = 0; i < trainImageNames.size(); i++)
    {
        string filename = trainDirName + trainImageNames[i];
        Mat img = imread(filename, CV_LOAD_IMAGE_GRAYSCALE);
        if(img.empty())
        {
            cout << "Train image " << filename << " can not be read." << endl;
        }
        else
        {
            readImageCount++;
        }// end if

        trainImages.push_back(img);
    } // end for

    if(!readImageCount)
    {
        cout << "All train images can not be read." << endl;
        return false;
    }
    else
    {
        cout << readImageCount << " train images were read." << endl;
    }

    cout << endl;

    return true;
}

static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints,
                            const vector<Mat>& trainImages, 
                            vector<vector<KeyPoint>>& trainKeypoints, 
                            Ptr<FeatureDetector>& featureDetector){
    cout << endl << "Extracting keypoints from images..." << endl;

    try{
        featureDetector->detect(queryImage, queryKeypoints);
    }
    catch(Ptr<FeatureDetector> a)
    {
        cout << "hmm" << endl;
    }

    cout << endl;
} // end void detectKeypoints

int main()
{
    const string defaultDetectorType = "SURF";
    const string defaultDescriptorType = "SURF";
    const string defaultMatcherType = "FlannBased";
    const string defaultQueryImageName = "D:/matching_to_many_images/query.png";
    const string defaultFileWithTrainImages = "D:/matching_to_many_images/train/trainImages.txt";
    const string defaultDirToSaveResImages = "D:/matching_to_many_images/results";

    Ptr<FeatureDetector> featureDetector;
    Ptr<DescriptorExtractor> descriptorExtractor;
    Ptr<DescriptorMatcher> descriptorMatcher;

    Mat queryImages;
    vector<Mat> trainImages;
    vector<string> trainImagesNames;

    vector<KeyPoint> queryKeypoints;
    vector<vector<KeyPoint>> trainKeypoints;

    if(!readImages(defaultQueryImageName, queryImages))
    {
        _getch();
        return -1;
    } // end if

    if(!readTrainImages(defaultFileWithTrainImages, trainImages, trainImagesNames))
    {
        _getch();
        return -1;
    }

    detectKeypoints(queryImages, queryKeypoints, trainImages, trainKeypoints, featureDetector);

    cout << "\n done \n";
    _getch();
    return 0;
} // end main method

Обновление:

#include <opencv2\highgui\highgui.hpp>
#include <opencv2\features2d\features2d.hpp>
#include <opencv2\contrib\contrib.hpp>
#include <iostream>
#include <fstream>
#include <conio.h>
#include <string>

using namespace std;
using namespace cv;

static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames);
static bool readImages(const string& queryImageName,  Mat& queryImage);
static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames);
static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, Ptr<FeatureDetector>& featureDetector);


static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames)
{
    trainFilenames.clear();

    ifstream file(filename.c_str());

    if(!file.is_open())
    {
        cout << "File can't open" << endl;
        return;
    }

    size_t pos = filename.rfind("\\");
    char dlmtr = '\\';

    if(pos == String::npos)
    {
        pos = filename.rfind('/');
        dlmtr = '/';
    }

    dirName = pos == string::npos ? "" : filename.substr(0, pos) + dlmtr;

    while(!file.eof())
    {
        string str; getline(file, str);
        if(str.empty()) break;
        trainFilenames.push_back(str);
    } // end while

    file.close();
} // end void readTrainFilenames


static bool readImages(const string& queryImageName,  Mat& queryImage)
{
    cout << "reading  images..." << endl;
    queryImage = imread(queryImageName, CV_LOAD_IMAGE_GRAYSCALE);
    if(queryImage.empty())
    {
        cout << "query image can not be read. \n";
        return false;
    } // end if


    return true;
}

static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames)
{
    cout << "reading training images..." << endl;
    string trainDirName = "D:/matching_to_many_images/";

    readTrainFilenames(trainFilename, trainDirName, trainImageNames);
    if(trainImageNames.empty())
    {
        cout << "Train image filenames can not be read." << endl;
        return false;
    } // end if

    int readImageCount = 0;
    for(size_t i = 0; i < trainImageNames.size(); i++)
    {
        string filename = trainDirName + trainImageNames[i];
        Mat img = imread(filename, CV_LOAD_IMAGE_GRAYSCALE);
        if(img.empty())
        {
            cout << "Train image " << filename << " can not be read." << endl;
        }
        else
        {
            readImageCount++;
        }// end if

        trainImages.push_back(img);
    } // end for

    if(!readImageCount)
    {
        cout << "All train images can not be read." << endl;
        return false;
    }
    else
    {
        cout << readImageCount << " train images were read." << endl;
    }

    cout << endl;

    return true;
}

static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, Ptr<FeatureDetector>& featureDetector){
    cout << endl << "Extracting keypoints from images..." << endl;

    featureDetector->detect(queryImage, queryKeypoints);


    cout << endl;
} // end void detectKeypoints

int main()
{
    const string defaultDetectorType = "SURF";
    const string defaultDescriptorType = "SURF";
    const string defaultMatcherType = "FlannBased";
    const string defaultQueryImageName = "D:/matching_to_many_images/query.png";
    const string defaultFileWithTrainImages = "D:/matching_to_many_images/train/trainImages.txt";
    const string defaultDirToSaveResImages = "D:/matching_to_many_images/results";

    Ptr<FeatureDetector> featureDetector;
    Ptr<DescriptorExtractor> descriptorExtractor;
    Ptr<DescriptorMatcher> descriptorMatcher;

    Mat queryImages;
    vector<Mat> trainImages;
    vector<string> trainImagesNames;

    vector<KeyPoint> queryKeypoints;
    vector<vector<KeyPoint>> trainKeypoints;

    if(!readImages(defaultQueryImageName, queryImages))
    {
        _getch();
        return -1;
    } // end if

    if(!readTrainImages(defaultFileWithTrainImages, trainImages, trainImagesNames))
    {
        _getch();
        return -1;
    }

    detectKeypoints(queryImages, queryKeypoints, featureDetector);

    cout << "\n done \n";
    _getch();
    return 0;
} // end main method

РЕШЕННЫЕ ПРОБЛЕМЫ:

#include <opencv2\highgui\highgui.hpp>
#include <opencv2\features2d\features2d.hpp>
#include <opencv2\contrib\contrib.hpp>
#include <opencv2\nonfree\nonfree.hpp>
#include <iostream>
#include <fstream>
#include <conio.h>
#include <string>

using namespace std;
using namespace cv;

const string defaultDetectorType = "SURF";
const string defaultDescriptorType = "SURF";
const string defaultMatcherType = "FlannBased";
const string defaultQueryImageName = "D:/matching_to_many_images/query.png";
const string defaultFileWithTrainImages = "D:/matching_to_many_images/train/trainImages.txt";
const string defaultDirToSaveResImages = "D:/matching_to_many_images/results";

static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames);
static bool readImages(const string& queryImageName,  Mat& queryImage);
static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames);
static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, Ptr<FeatureDetector>& featureDetector);
static bool createDetectorDescriptorMatcher(const string& detectorType, 
                                        const string& descriptorType, 
                                        const string& matcherType,
                                        Ptr<FeatureDetector>& featureDetector,
                                        Ptr<DescriptorExtractor>& descriptorExtractor,
                                        Ptr<DescriptorMatcher>& descriptorMatcher);

static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames)
{
    trainFilenames.clear();

    ifstream file(filename.c_str());

    if(!file.is_open())
    {
        cout << "File can't open" << endl;
        return;
    }

    size_t pos = filename.rfind("\\");
    char dlmtr = '\\';

    if(pos == String::npos)
    {
        pos = filename.rfind('/');
        dlmtr = '/';
    }

    dirName = pos == string::npos ? "" : filename.substr(0, pos) + dlmtr;

    while(!file.eof())
    {
        string str; getline(file, str);
        if(str.empty()) break;
        trainFilenames.push_back(str);
    } // end while

    file.close();
} // end void readTrainFilenames


static bool readImages(const string& queryImageName,  Mat& queryImage)
{
    cout << "reading  images..." << endl;
    queryImage = imread(queryImageName, CV_LOAD_IMAGE_GRAYSCALE);
    if(queryImage.empty())
    {
        cout << "query image can not be read. \n";
        return false;
    } // end if


    return true;
}

static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames)
{
    cout << "reading training images..." << endl;
    string trainDirName = "D:/matching_to_many_images/";

    readTrainFilenames(trainFilename, trainDirName, trainImageNames);
    if(trainImageNames.empty())
    {
        cout << "Train image filenames can not be read." << endl;
        return false;
    } // end if

    int readImageCount = 0;
    for(size_t i = 0; i < trainImageNames.size(); i++)
    {
        string filename = trainDirName + trainImageNames[i];
        Mat img = imread(filename, CV_LOAD_IMAGE_GRAYSCALE);
        if(img.empty())
        {
            cout << "Train image " << filename << " can not be read." << endl;
        }
        else
        {
            readImageCount++;
        }// end if

        trainImages.push_back(img);
    } // end for

    if(!readImageCount)
    {
        cout << "All train images can not be read." << endl;
        return false;
    }
    else
    {
        cout << readImageCount << " train images were read." << endl;
    }

    cout << endl;

    return true;
}

static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, Ptr<FeatureDetector>& featureDetector){
    cout << endl << "Extracting keypoints from images..." << endl;

    if(queryImage.empty())
    {
        cout << "Query Image EMPTY" << endl;
    } 
    else{
        cout << "Query Image FILLED" << endl;
    }

    featureDetector->detect(queryImage, queryKeypoints);


    cout << endl;
} // end void detectKeypoints

static bool createDetectorDescriptorMatcher(const string& detectorType, 
                                        const string& descriptorType, 
                                        const string& matcherType,
                                        Ptr<FeatureDetector>& featureDetector,
                                        Ptr<DescriptorExtractor>& descriptorExtractor,
                                        Ptr<DescriptorMatcher>& descriptorMatcher)
{
    cout << "Creating feature detector, descriptor extractor and descriptor matcher ... " << endl;
    featureDetector = FeatureDetector::create(detectorType);
    descriptorExtractor = DescriptorExtractor::create(descriptorType);
    descriptorMatcher = DescriptorMatcher::create(matcherType);
    cout << endl;

    if(featureDetector.empty())
    {
        cout << "feature detector empty" << endl;
    }

    if(descriptorExtractor.empty())
    {
        cout << "descriptor extractor empty" << endl;
    }

    if(descriptorMatcher.empty())
    {
        cout << "descriptor matcher empty" << endl;
    } 

    bool isCreated = !(featureDetector.empty() || descriptorExtractor.empty() || descriptorMatcher.empty());

    if(!isCreated)
    {
        cout << "can not create feature detector or descriptor extractor or descriptor matcher of given types." << endl;
    } // end if

    return isCreated;
} // end void createDetectorDescriptorMatcher

int main()
{
    initModule_nonfree();
    string detectorType = defaultDetectorType;
    string descriptorType = defaultDetectorType;
    string matcherType = defaultMatcherType;
    string queryImageName = defaultQueryImageName;
    string fileWithTrainImages = defaultFileWithTrainImages;
    string dirToSaveResImages = defaultDirToSaveResImages;

    Ptr<FeatureDetector> featureDetector = FeatureDetector::create("SURF");
    Ptr<DescriptorExtractor> descriptorExtractor = DescriptorExtractor::create("SURF");
    Ptr<DescriptorMatcher> descriptorMatcher;

    if(!createDetectorDescriptorMatcher(detectorType, descriptorType, matcherType, featureDetector, descriptorExtractor, descriptorMatcher))
    {

        _getch();
        return -1;
    }


    Mat queryImages;
    vector<Mat> trainImages;
    vector<string> trainImagesNames;

    vector<KeyPoint> queryKeypoints;
    vector<vector<KeyPoint>> trainKeypoints;

    if(!readImages(defaultQueryImageName, queryImages))
    {
        _getch();
        return -1;
    } // end if

    if(!readTrainImages(defaultFileWithTrainImages, trainImages, trainImagesNames))
    {
        _getch();
        return -1;
    }

    detectKeypoints(queryImages, queryKeypoints, featureDetector);

    cout << "\n done \n";
    _getch();
    return 0;
} // end main method

ПОЛНЫЕ ПРИМЕРЫ КОДОВ, СООТВЕТСТВУЮЩИХ МНОЖЕСТВУ ИЗОБРАЖЕНИЙ:

#include <opencv2\highgui\highgui.hpp>
#include <opencv2\features2d\features2d.hpp>
#include <opencv2\contrib\contrib.hpp>
#include <opencv2\nonfree\nonfree.hpp>
#include <iostream>
#include <fstream>
#include <conio.h>
#include <string>

using namespace std;
using namespace cv;

const string defaultDetectorType = "SURF";
const string defaultDescriptorType = "SURF";
const string defaultMatcherType = "FlannBased";
const string defaultQueryImageName = "D:/matching_to_many_images/query.png";
const string defaultFileWithTrainImages = "D:/matching_to_many_images/train/trainImages.txt";
const string defaultDirToSaveResImages = "D:/matching_to_many_images/results";

static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames);
static bool readImages(const string& queryImageName,  Mat& queryImage);
static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames);
static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, const vector<Mat>& trainImages, vector<vector<KeyPoint>>& trainKeypoints, Ptr<FeatureDetector>& featureDetector);
static bool createDetectorDescriptorMatcher(const string& detectorType, 
                                        const string& descriptorType, 
                                        const string& matcherType,
                                        Ptr<FeatureDetector>& featureDetector,
                                        Ptr<DescriptorExtractor>& descriptorExtractor,
                                        Ptr<DescriptorMatcher>& descriptorMatcher);
static void computeDescriptors(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, Mat& queryDescriptors, 
    const vector<Mat>& trainImages, vector<vector<KeyPoint>>& trainKeypoints, vector<Mat>& trainDescriptors,
    Ptr<DescriptorExtractor>& descriptorExtractor);
static void matchDescriptors(const Mat& queryDescriptors, const vector<Mat>& trainDescriptors, vector<DMatch>& matches, Ptr<DescriptorMatcher>& descriptorMatcher);
static void maskMatchesByTrainImgIdx(const vector<DMatch>& matches, int trainImgIdx, vector<char>& mask);

static void readTrainFilenames(const string& filename, string& dirName, vector<string>& trainFilenames)
{
    trainFilenames.clear();

    ifstream file(filename.c_str());

    if(!file.is_open())
    {
        cout << "File can't open" << endl;
        return;
    }

    size_t pos = filename.rfind("\\");
    char dlmtr = '\\';

    if(pos == String::npos)
    {
        pos = filename.rfind('/');
        dlmtr = '/';
    }

    dirName = pos == string::npos ? "" : filename.substr(0, pos) + dlmtr;

    while(!file.eof())
    {
        string str; getline(file, str);
        if(str.empty()) break;
        trainFilenames.push_back(str);
    } // end while

    file.close();
} // end void readTrainFilenames


static bool readImages(const string& queryImageName,  Mat& queryImage)
{
    cout << "reading  images..." << endl;
    queryImage = imread(queryImageName, CV_LOAD_IMAGE_GRAYSCALE);
    if(queryImage.empty())
    {
        cout << "query image can not be read. \n";
        return false;
    } // end if


    return true;
}

static bool readTrainImages(const string& trainFilename, vector<Mat>& trainImages, vector<string>& trainImageNames)
{
    cout << "reading training images..." << endl;
    string trainDirName = "D:/matching_to_many_images/";

    readTrainFilenames(trainFilename, trainDirName, trainImageNames);
    if(trainImageNames.empty())
    {
        cout << "Train image filenames can not be read." << endl;
        return false;
    } // end if

    int readImageCount = 0;
    for(size_t i = 0; i < trainImageNames.size(); i++)
    {
        string filename = trainDirName + trainImageNames[i];
        Mat img = imread(filename, CV_LOAD_IMAGE_GRAYSCALE);
        if(img.empty())
        {
            cout << "Train image " << filename << " can not be read." << endl;
        }
        else
        {
            readImageCount++;
        }// end if

        trainImages.push_back(img);
    } // end for

    if(!readImageCount)
    {
        cout << "All train images can not be read." << endl;
        return false;
    }
    else
    {
        cout << readImageCount << " train images were read." << endl;
    }

    cout << endl;

    return true;
}

static void detectKeypoints(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, const vector<Mat>& trainImages, vector<vector<KeyPoint>>& trainKeypoints, Ptr<FeatureDetector>& featureDetector){
    cout << endl << "Extracting keypoints from images..." << endl;

    if(queryImage.empty())
    {
        cout << "Query Image EMPTY" << endl;
    } 
    else{
        cout << "Query Image FILLED" << endl;
    }

    featureDetector->detect(queryImage, queryKeypoints);
    featureDetector->detect(trainImages, trainKeypoints);

    cout << endl;
} // end void detectKeypoints

static bool createDetectorDescriptorMatcher(const string& detectorType, 
                                        const string& descriptorType, 
                                        const string& matcherType,
                                        Ptr<FeatureDetector>& featureDetector,
                                        Ptr<DescriptorExtractor>& descriptorExtractor,
                                        Ptr<DescriptorMatcher>& descriptorMatcher)
{
    cout << "Creating feature detector, descriptor extractor and descriptor matcher ... " << endl;
    featureDetector = FeatureDetector::create(detectorType);
    descriptorExtractor = DescriptorExtractor::create(descriptorType);
    descriptorMatcher = DescriptorMatcher::create(matcherType);
    cout << endl;

    if(featureDetector.empty())
    {
        cout << "feature detector empty" << endl;
    }

    if(descriptorExtractor.empty())
    {
        cout << "descriptor extractor empty" << endl;
    }

    if(descriptorMatcher.empty())
    {
        cout << "descriptor matcher empty" << endl;
    } 

    bool isCreated = !(featureDetector.empty() || descriptorExtractor.empty() || descriptorMatcher.empty());

    if(!isCreated)
    {
        cout << "can not create feature detector or descriptor extractor or descriptor matcher of given types." << endl;
    } // end if

    return isCreated;
} // end void createDetectorDescriptorMatcher

static void computeDescriptors(const Mat& queryImage, vector<KeyPoint>& queryKeypoints, Mat& queryDescriptors, 
    const vector<Mat>& trainImages, vector<vector<KeyPoint>>& trainKeypoints, vector<Mat>& trainDescriptors,
    Ptr<DescriptorExtractor>& descriptorExtractor)
{
    cout << "computing descriptors for keypoints..." << endl;
    descriptorExtractor->compute(queryImage, queryKeypoints, queryDescriptors);
    descriptorExtractor->compute(trainImages, trainKeypoints, trainDescriptors);

    int totalTrainDesc = 0;
    for(vector<Mat>::const_iterator tdIter = trainDescriptors.begin(); tdIter != trainDescriptors.end(); tdIter++)
        totalTrainDesc += tdIter->rows;

    cout << "Query descriptors count : " << queryDescriptors.rows << "; Total train descriptors count : " << totalTrainDesc << endl;
    cout << endl;
} // end void computeDescriptors

static void matchDescriptors(const Mat& queryDescriptors, const vector<Mat>& trainDescriptors, vector<DMatch>& matches, Ptr<DescriptorMatcher>& descriptorMatcher)
{
    cout << "Set train descriptors collection in the matcher and match query descriptors to them..." << endl;
    TickMeter tm;
    tm.start();
    descriptorMatcher->add(trainDescriptors);
    descriptorMatcher->train();
    tm.stop();
    double buildTime = tm.getTimeMilli();

    tm.start();
    descriptorMatcher->match(queryDescriptors, matches);
    tm.stop();
    double matchTime = tm.getTimeMilli();

    CV_Assert(queryDescriptors.rows == (int)matches.size() || matches.empty());

    cout << "Number of matches: " << matches.size() << endl;
    cout << "Build time: " << buildTime << " ms; Match time: " << matchTime << " ms" << endl;
    cout << endl;
} // end void matchDescriptors

static void saveResultImages(const Mat& queryImage, const vector<KeyPoint>& queryKeypoints,
    const vector<Mat>& trainImages, const vector<vector<KeyPoint>> &trainKeypoints, const vector<DMatch>& matches, 
    const vector<string>& trainImageNames, const string& resultDir)
{
    cout << "Save results..." << endl;
    Mat drawImg;
    vector<char> mask;
    for(size_t i = 0; i < trainImages.size(); i++)
    {
        if(!trainImages[i].empty())
        {
            maskMatchesByTrainImgIdx(matches, (int)i, mask);
            drawMatches(queryImage, queryKeypoints, trainImages[i], trainKeypoints[i], matches, drawImg, Scalar(255, 0, 0), Scalar(0, 255, 255), mask);
            string filename = resultDir + "/res_" + trainImageNames[i];
            if(!imwrite(filename, drawImg))
            {
                cout << "Image " << filename << " can not be saved (may be because directory " << resultDir << " does not exist" << endl;
            } // end if
        } // end if
    }
} // end void saveResultImages

static void maskMatchesByTrainImgIdx(const vector<DMatch>& matches, int trainImgIdx, vector<char>& mask)
{
    mask.resize(matches.size());
    fill(mask.begin(), mask.end(), 0);
    for(size_t i = 0; i < matches.size(); i++)
    {
        if(matches[i].imgIdx == trainImgIdx)
        {
            mask[i] = 1;
        }
    }
} // end void maskMatchesByTrainImgIdx

int main()
{
    initModule_nonfree();
    string detectorType = defaultDetectorType;
    string descriptorType = defaultDetectorType;
    string matcherType = defaultMatcherType;
    string queryImageName = defaultQueryImageName;
    string fileWithTrainImages = defaultFileWithTrainImages;
    string dirToSaveResImages = defaultDirToSaveResImages;

    Ptr<FeatureDetector> featureDetector = FeatureDetector::create("SURF");
    Ptr<DescriptorExtractor> descriptorExtractor = DescriptorExtractor::create("SURF");
    Ptr<DescriptorMatcher> descriptorMatcher;

    if(!createDetectorDescriptorMatcher(detectorType, descriptorType, matcherType, featureDetector, descriptorExtractor, descriptorMatcher))
    {

        _getch();
        return -1;
    }

    Mat queryImages;
    vector<Mat> trainImages;
    vector<string> trainImagesNames;

    vector<KeyPoint> queryKeypoints;
    vector<vector<KeyPoint>> trainKeypoints;

    if(!readImages(defaultQueryImageName, queryImages))
    {
        _getch();
        return -1;
    } // end if

    if(!readTrainImages(defaultFileWithTrainImages, trainImages, trainImagesNames))
    {
        _getch();
        return -1;
    }

    detectKeypoints(queryImages, queryKeypoints, trainImages, trainKeypoints, featureDetector);

    Mat queryDescriptors;
    vector<Mat> trainDescriptors;

    computeDescriptors(queryImages, queryKeypoints, queryDescriptors, trainImages, trainKeypoints, trainDescriptors, descriptorExtractor);

    vector<DMatch> matches;
    matchDescriptors(queryDescriptors, trainDescriptors, matches, descriptorMatcher);

    saveResultImages(queryImages, queryKeypoints, trainImages, trainKeypoints, matches, trainImagesNames, dirToSaveResImages);

    cout << "\n done \n";
    _getch();
    return 0;
} // end main method