特征匹配（提取和匹配描述符FeatureDetector&DescriptorExtractor）

void featureMatch() {

    cv::TickMeter meter;

    meter.start();

    Mat image1 = imread(MYPICTUREPATH "lena.jpg");

    Mat image2 = imread(MYPICTUREPATH "lena_face.jpg");

    //Mat image1 = imread(MYPICTUREPATH "test.jpg");

    //Mat image2 = imread(MYPICTUREPATH "test_templ.jpg");

    //! 1.检测关键点

    Ptr<AKAZE> akaze=AKAZE::create();

    vector<KeyPoint> keypoints1, keypoints2;

    akaze->detect(image1, keypoints1);

    akaze->detect(image2, keypoints2);

    qDebug() << "1.检测关键点";

    //! 2.计算/提取描述符

    Mat descriptor1, descriptor2;

    akaze->compute(image1, keypoints1, descriptor1);

    akaze->compute(image2, keypoints2, descriptor2);

    qDebug() << "2.计算/提取描述符";

    //! 3.描述符匹配

    //! 注意：若create()的实参选择不正确，将报出如下错误：

    //! OpenCV: terminate handler is called! The last OpenCV error is:

    //! OpenCV(4.6.0) Error: Unsupported format or combination of formats (> type=0

    //! > ) in buildIndex_, file D:\Qt-OpenCV\OpenCV-Source\modules\flann\src\miniflann.cpp, line 336

    Ptr<DescriptorMatcher> descMatcher = DescriptorMatcher::create(DescriptorMatcher::FLANNBASED);

    //Ptr<DescriptorMatcher> descMatcher = DescriptorMatcher::create(DescriptorMatcher::BRUTEFORCE);

    qDebug() << "3.描述符匹配";

    //! 4.调用match函数

    vector<DMatch> matches;

    descMatcher->match(descriptor1, descriptor2, matches);

    qDebug() << "4.调用match函数";

    //! 5.drawMatches可以用来自动创建用于显示的适当输出结果

    Mat dispImg;

    drawMatches(image1, keypoints1, image2, keypoints2, matches, dispImg);

    /*

    drawMatches(image1,

                keypoints1,

                image2,

                keypoints2,

                matches,

                dispImg,

                Scalar(0,255,0), // green for matched

                Scalar::all(-1), // unmatched color (default)

                vector<char>(),  // empty mask

                DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS);

    */

    qDebug() << "5.drawMatches可以用来自动创建用于显示的适当输出结果";

    imshow("Image-match", dispImg);

    meter.stop();

    qDebug() << "耗时：" << meter.getTimeMilli() << "毫秒";//

}