2019-07-28 18:23:58 -0500 received badge ● Popular Question (source) 2018-08-20 10:43:02 -0500 received badge ● Famous Question (source) 2018-01-11 23:46:51 -0500 received badge ● Notable Question (source) 2017-10-22 09:02:38 -0500 received badge ● Popular Question (source) 2016-06-07 04:11:49 -0500 commented question Coordinates of keypoints using FLANN matcher I tried with histogram comparison but I still have better results with keypoints, only if I could check that all the points are in the same Y axis would be enough for my simple application... 2016-06-06 09:50:12 -0500 asked a question Coordinates of keypoints using FLANN matcher I have two images (faces) and I want to check if it is the same person or not. So far I implemented as it is in this tutorial and I obtained this results: So far I could work with that. I would just need to check that each point from left and right are in the same horizontal lines I could same it is the same face in both images. But the thing is, how do I get the coordinates of each of the points shown in the images above? This is the code:  // Step 1: Detect the keypoints using SURF detect. int minHessian = 400; SurfFeatureDetector detector(minHessian); std::vector keypoints_1, keypoints_2; detector.detect(roiFrameMaster, keypoints_1); detector.detect(roiFrameSlave, keypoints_2); // Step 2: Calculate descriptors (feature vectors). SurfDescriptorExtractor extractor; Mat descriptors_1, descriptors_2; extractor.compute(roiFrameMaster, keypoints_1, descriptors_1); extractor.compute(roiFrameSlave, keypoints_2, descriptors_2); // Step 3 : Matching descriptor vectors using FLANN matcher. FlannBasedMatcher matcher; std::vector< DMatch > matches; matcher.match(descriptors_1, descriptors_2, matches); double max_dist = 0; double min_dist = 100; //-- Quick calculation of max and min distances between keypoints for( int i = 0; i < descriptors_1.rows; i++ ) { double dist = matches[i].distance; if(dist < min_dist) min_dist = dist; if(dist > max_dist) max_dist = dist; } printf("-- Max dist : %f \n", max_dist ); printf("-- Min dist : %f \n", min_dist ); //-- Draw only "good" matches (i.e. whose distance is less than 2*min_dist, //-- or a small arbitary value ( 0.02 ) in the event that min_dist is very //-- small) std::vector< DMatch > good_matches; for( int i = 0; i < descriptors_1.rows; i++ ) { if( matches[i].distance <= max(2*min_dist, 0.02)) good_matches.push_back( matches[i]); } //-- Draw only "good" matches Mat img_matches; drawMatches(roiFrameMaster, keypoints_1, roiFrameSlave, keypoints_2, good_matches, img_matches, Scalar::all(-1), Scalar::all(-1), vector(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS ); //-- Show detected matches imshow( "Good Matches", img_matches);  Thanks for the help. 2016-04-21 03:53:15 -0500 commented answer About opencv_traincascade.... Sorry for the delay....It did not train very well....If I move the camera around there are no false detections, but it also does not detect the phone but next to it in the background as you can see here . Even thought I would like to make it work, I've been using in parallel find_object_2d ROS package and managed to do what I needed, but it is no training model..... 2016-04-19 05:32:30 -0500 commented answer About opencv_traincascade.... After leaving it training with this parameters: PARAMETERS: cascadeDirName: training vecFileName: positives.vec bgFileName: bg.txt numPos: 220 numNeg: 2200 numStages: 25 precalcValBufSize[Mb] : 4096 precalcIdxBufSize[Mb] : 4096 stageType: BOOST featureType: LBP sampleWidth: 80 sampleHeight: 80 boostType: GAB minHitRate: 0.998 maxFalseAlarmRate: 0.5 weightTrimRate: 0.95 maxDepth: 1 maxWeakCount: 100  I see that it got stuck: ===== TRAINING 14-stage ===== &objects) { int i, div=2; Mat frame_gray; resize(frame, frame_gray, Size(frame.cols/div,frame.rows/div)); cvtColor(frame_gray, frame_gray ... 2016-03-25 06:39:18 -0500 commented question Autotools with opencv (undefined reference to cv::meanShift) Solved it by adding AM_LDFLAGS = pkg-config --libs opencv to the Makefile.am 2016-03-24 07:52:20 -0500 edited question Autotools with opencv (undefined reference to cv::meanShift) Hello, I'm using autotools to build a library that incorporates several custom functions that are based on opencv that I will use in another project. So first I build this library with the following structure: src/ (all .cpp files) dpf-template/ (all .h files) test/ configure.ac Makefile.am dpf_template.pc.in  configure.ac: AC_PREREQ([2.69]) AC_INIT([calc_mean], [1.0]) AM_INIT_AUTOMAKE([foreign]) AM_MAINTAINER_MODE([enable]) AC_CONFIG_MACRO_DIR([m4]) # Checks for programs. AC_PROG_CXX AC_PROG_LIBTOOL #PKG_CHECK_MODULES([calc_mean]) AC_OUTPUT([Makefile src/Makefile test/Makefile dpf_template.pc])  Makefile.am: ACLOCAL_AMFLAGS = -I m4 AUTOMAKE_OPTIONS = foreign SUBDIRS = src test pkgconfigdir = $(libdir)/pkgconfig pkgconfig_DATA = dpf_template.pc  src/Makefile.am lib_LTLIBRARIES = libdpf_template.la libdpf_template_la_SOURCES = \ (plus all the files in src/*.cpp and dpf-template/*.h AM_CPPFLAGS = -I$(top_srcdir) pkg-config --cflags opencv AM_CFLAGS = -g -Wall pkg-config --cflags opencv -I/usr/include/eigen3 AM_CXXFLAGS=pkg-config --cflags opencv libdpf_templateincludedir = \$(includedir)/dpf_template libdpf_templateinclude_HEADERS = \ (plus all the files in dpf-template/*.h)  I also saw where opencv.pc is and then checked that it is in PKG_CONFIG_PATH. With these, I run make and make install with no errors. So far so go, but when I build a simple project that includes this dpf_template.so (through .pc file) and I have only one error which is libdpf_template.so: undefined reference to cv::meanShift(cv::_InputArray const&, cv::Rect_&, cv::TermCriteria)' collect2: error: ld returned 1 exit status ` Shouldn't I have been prompted something when I build the libdpf_template? Thanks for the help.