OpenCV 3.0.0 SurfFeatureDetector and SurfDescriptorExtractor Errors
15,166
Solution 1
Occurred some modifications in the OpenCV 3.0 with these tools.
Where is
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detector.detect(img_object, keypoints_object);
should bedetector
->detect(img_object, keypoints_object);
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SurfDescriptorExtractor extractor;
should bePtr<SURF> extractor = SURF::create();
Take a look at this website
The others erros should desapear now, I guess.
Solution 2
I had the same problems. I managed to solve combining answers from other users and adding some more modifications:
- added
#include "opencv2/imgproc.hpp"
otherwise line function is not recognised; -
Ptr<SURF> detector = SURF.create(minHessian);
substituted asPtr<SURF> detector = SURF::create(minHessian);
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detector.
substituted asdetector->
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SurfDescriptorExtractor extractor;
substitued asPtr<SURF> extractor = SURF::create();
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extractor.
substituted asextractor->
Furnishing two images as input, namely a template
VERY IMPORTANT: I'm using opencv 3.3.1 from git, which was built using opencv contrib.
Author by
Admin
Updated on July 23, 2022Comments
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Admin almost 2 years
I am attempting to implement the OpenCV 3.0.0 SURF Feature Description and Detection but after running the sample code on the OpenCV site, I receive a load of errors all related to SURF. Any idea of what could be going wrong? Thanks!
#include <stdio.h> #include <iostream> #include "opencv2/core.hpp" #include "opencv2/features2d.hpp" #include "opencv2/highgui.hpp" #include "opencv2/calib3d.hpp" #include "opencv2/xfeatures2d.hpp" #include <opencv2/nonfree/nonfree.hpp> using namespace cv; using namespace cv::xfeatures2d; void readme(); /** @function main */ int main(int argc, char** argv) { if (argc != 3) { readme(); return -1; } Mat img_object = imread(argv[1], IMREAD_GRAYSCALE); Mat img_scene = imread(argv[2], IMREAD_GRAYSCALE); if (!img_object.data || !img_scene.data) { std::cout << " --(!) Error reading images " << std::endl; return -1; } //-- Step 1: Detect the keypoints using SURF Detector int minHessian = 400; Ptr<SURF> detector = SURF.create(minHessian); std::vector<KeyPoint> keypoints_object, keypoints_scene; detector.detect(img_object, keypoints_object); detector.detect(img_scene, keypoints_scene); //-- Step 2: Calculate descriptors (feature vectors) SurfDescriptorExtractor extractor; Mat descriptors_object, descriptors_scene; extractor.compute(img_object, keypoints_object, descriptors_object); extractor.compute(img_scene, keypoints_scene, descriptors_scene); //-- Step 3: Matching descriptor vectors using FLANN matcher FlannBasedMatcher matcher; std::vector< DMatch > matches; matcher.match(descriptors_object, descriptors_scene, matches); double max_dist = 0; double min_dist = 100; //-- Quick calculation of max and min distances between keypoints for (int i = 0; i < descriptors_object.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 3*min_dist ) std::vector< DMatch > good_matches; for (int i = 0; i < descriptors_object.rows; i++) { if (matches[i].distance < 3 * min_dist) { good_matches.push_back(matches[i]); } } Mat img_matches; drawMatches(img_object, keypoints_object, img_scene, keypoints_scene, good_matches, img_matches, Scalar::all(-1), Scalar::all(-1), std::vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS); //-- Localize the object std::vector<Point2f> obj; std::vector<Point2f> scene; for (int i = 0; i < good_matches.size(); i++) { //-- Get the keypoints from the good matches obj.push_back(keypoints_object[good_matches[i].queryIdx].pt); scene.push_back(keypoints_scene[good_matches[i].trainIdx].pt); } Mat H = findHomography(obj, scene, RANSAC); //-- Get the corners from the image_1 ( the object to be "detected" ) std::vector<Point2f> obj_corners(4); obj_corners[0] = cvPoint(0, 0); obj_corners[1] = cvPoint(img_object.cols, 0); obj_corners[2] = cvPoint(img_object.cols, img_object.rows); obj_corners[3] = cvPoint(0, img_object.rows); std::vector<Point2f> scene_corners(4); perspectiveTransform(obj_corners, scene_corners, H); //-- Draw lines between the corners (the mapped object in the scene - image_2 ) line(img_matches, scene_corners[0] + Point2f(img_object.cols, 0), scene_corners[1] + Point2f(img_object.cols, 0), Scalar(0, 255, 0), 4); line(img_matches, scene_corners[1] + Point2f(img_object.cols, 0), scene_corners[2] + Point2f(img_object.cols, 0), Scalar(0, 255, 0), 4); line(img_matches, scene_corners[2] + Point2f(img_object.cols, 0), scene_corners[3] + Point2f(img_object.cols, 0), Scalar(0, 255, 0), 4); line(img_matches, scene_corners[3] + Point2f(img_object.cols, 0), scene_corners[0] + Point2f(img_object.cols, 0), Scalar(0, 255, 0), 4); //-- Show detected matches imshow("Good Matches & Object detection", img_matches); waitKey(0); return 0; } /** @function readme */ void readme() { std::cout << " Usage: ./SURF_descriptor <img1> <img2>" << std::endl; }
Errors:
1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(34): warning C4832: token '.' is illegal after UDT 'cv::xfeatures2d::SURF' 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(111) : see declaration of 'cv::xfeatures2d::SURF' 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(34): error C2275: 'cv::xfeatures2d::SURF' : illegal use of this type as an expression 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(111) : see declaration of 'cv::xfeatures2d::SURF' 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(34): error C2228: left of '.create' must have class/struct/union 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(38): error C2039: 'detect' : is not a member of 'cv::Ptr<cv::xfeatures2d::SURF>' 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(39): error C2039: 'detect' : is not a member of 'cv::Ptr<cv::xfeatures2d::SURF>' 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(42): error C2259: 'cv::xfeatures2d::SURF' : cannot instantiate abstract class 1> due to following members: 1> 'void cv::xfeatures2d::SURF::setHessianThreshold(double)' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(127) : see declaration of 'cv::xfeatures2d::SURF::setHessianThreshold' 1> 'double cv::xfeatures2d::SURF::getHessianThreshold(void) const' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(128) : see declaration of 'cv::xfeatures2d::SURF::getHessianThreshold' 1> 'void cv::xfeatures2d::SURF::setNOctaves(int)' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(130) : see declaration of 'cv::xfeatures2d::SURF::setNOctaves' 1> 'int cv::xfeatures2d::SURF::getNOctaves(void) const' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(131) : see declaration of 'cv::xfeatures2d::SURF::getNOctaves' 1> 'void cv::xfeatures2d::SURF::setNOctaveLayers(int)' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(133) : see declaration of 'cv::xfeatures2d::SURF::setNOctaveLayers' 1> 'int cv::xfeatures2d::SURF::getNOctaveLayers(void) const' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(134) : see declaration of 'cv::xfeatures2d::SURF::getNOctaveLayers' 1> 'void cv::xfeatures2d::SURF::setExtended(bool)' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(136) : see declaration of 'cv::xfeatures2d::SURF::setExtended' 1> 'bool cv::xfeatures2d::SURF::getExtended(void) const' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(137) : see declaration of 'cv::xfeatures2d::SURF::getExtended' 1> 'void cv::xfeatures2d::SURF::setUpright(bool)' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(139) : see declaration of 'cv::xfeatures2d::SURF::setUpright' 1> 'bool cv::xfeatures2d::SURF::getUpright(void) const' : is abstract 1> c:\users\belayachiry\documents\opencv\opencv\build\include\opencv2\nonfree\nonfree.hpp(140) : see declaration of 'cv::xfeatures2d::SURF::getUpright' 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(87): warning C4018: '<' : signed/unsigned mismatch 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(105): warning C4244: 'argument' : conversion from 'int' to 'float', possible loss of data 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(105): error C3861: 'line': identifier not found 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(106): warning C4244: 'argument' : conversion from 'int' to 'float', possible loss of data 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(106): error C3861: 'line': identifier not found 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(107): warning C4244: 'argument' : conversion from 'int' to 'float', possible loss of data 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(107): error C3861: 'line': identifier not found 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(108): warning C4244: 'argument' : conversion from 'int' to 'float', possible loss of data 1>c:\users\belayachiry\documents\visual studio 2013\projects\imagewatch\imagewatch\source.cpp(108): error C3861: 'line': identifier not found