我使用 Sift/Surf 和 ORB，但有时我在使用 drawMatch 函数时遇到问题。
这里的错误：
OpenCV 错误：drawMatches 中断言失败 (i2 >= 0 && i2 = 0 && i2
代码 ：
drawMatchPoints(img1,keypoints_img1,img2,keypoints_img2,matches);
我尝试用 img2 和 keypoints_img2 反转图像 1,keypoints img1 ，如下所示：
drawMatchPoints(img2,keypoints_img2,img1,keypoints_img1,matches);
对应于我正在做单应性的函数：
void drawMatchPoints(cv::Mat image1,std::vector<KeyPoint> keypoints_img1,
cv::Mat image2,std::vector<KeyPoint> keypoints_img2,std::vector<cv::DMatch> matches){
cv::Mat img_matches;
drawMatches( image1, keypoints_img1, image2, keypoints_img2,
matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
std::cout << "Number of good matching " << (int)matches.size() << "\n" << endl;
//-- Localize the object
std::vector<Point2f> obj;
std::vector<Point2f> scene;
for( int i = 0; i < matches.size(); i++ )
{
//-- Get the keypoints from the good matches
obj.push_back( keypoints_img1[ matches[i].queryIdx ].pt );
scene.push_back( keypoints_img2[matches[i].trainIdx ].pt );
}
Mat H = findHomography( obj, scene, CV_RANSAC );
std::cout << "Size of homography " << *H.size << std::endl ;
//-- 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( image1.cols, 0 );
obj_corners[2] = cvPoint( image1.cols, image1.rows ); obj_corners[3] = cvPoint( 0, image1.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( image1.cols, 0), scene_corners[1] + Point2f( image1.cols, 0), Scalar(0, 255, 0), 4 );
line( img_matches, scene_corners[1] + Point2f( image1.cols, 0), scene_corners[2] + Point2f( image1.cols, 0), Scalar( 0, 255, 0), 4 );
line( img_matches, scene_corners[2] + Point2f( image1.cols, 0), scene_corners[3] + Point2f( image1.cols, 0), Scalar( 0, 255, 0), 4 );
line( img_matches, scene_corners[3] + Point2f( image1.cols, 0), scene_corners[0] + Point2f( image1.cols, 0), Scalar( 0, 255, 0), 4 );
//-- Show detected matches
cv::imshow( "Good Matches & Object detection", img_matches );
cv::waitKey(5000);
}
但我仍然有错误！
我注意到当我的 keypoints_img1 的大小时发生错误is lower比我的 keypoints_img2 的大小：
尺寸关键点1：244
- 尺寸关键点2：400
因此，如果我反转两张图片的加载，这是可行的，但如果我的第一张图片比我的第二张图片有更多的关键点，我现在不能提前...
我的代码（最重要的步骤）为了创建功能：
init_Sift(400,5,0.04,25,1.6);
void init_Sift(int nf,int nOctaveL,double contrastThresh, double edgeThresh,double sigma){
this->nfeatureSift=nf;
this->nOctaveLayerSift=nOctaveL;
this->contrastThresholdSift=contrastThresh;
this->edgeThresholdSift=edgeThresh;
this->sigmaSift=sigma;}
cv::FeatureDetector* detector=new SiftFeatureDetector(nfeatureSift,nOctaveLayerSift,contrastThresholdSift,edgeThresholdSift,sigmaSift);
cv::DescriptorExtractor* extractor=new SiftDescriptorExtractor
extractor->compute( image, keypoints, descriptors );
配套部分：
std::cout << "Type of matcher : " << type_of_matcher << std::endl;
if (type_of_matcher=="FLANN" || type_of_matcher=="BF"){
std::vector<KeyPoint> keypoints_img1 = keyfeatures.compute_Keypoints(img1);
std::vector<KeyPoint> keypoints_img2 = keyfeatures.compute_Keypoints(img2);
cv::Mat descriptor_img1 = keyfeatures.compute_Descriptors(img1);
cv::Mat descriptor_img2 = keyfeatures.compute_Descriptors(img2);
std::cout << "Size keyPoint1 " << keypoints_img1.size() << "\n" << std::endl;
std::cout << "Size keyPoint2 " << keypoints_img2.size() << "\n" << std::endl;
//Flann with sift or surf
if (type_of_matcher=="FLANN"){
Debug::info("USING Matcher FLANN");
fLmatcher.match(descriptor_img1,descriptor_img2,matches);
double max_dist = 0; double min_dist = 100;
//-- Quick calculation of max and min distances between keypoints
for( int i = 0; i < descriptor_img1.rows; i++ ){
double dist = matches[i].distance;
if( dist < min_dist ) min_dist = dist;
if( dist > max_dist ) max_dist = dist;
}
std::vector< DMatch > good_matches;
for( int i = 0; i < descriptor_img1.rows; i++ )
{ if( matches[i].distance <= max(2*min_dist, 0.02) )
{ good_matches.push_back( matches[i]); }
}
std::cout << "Size of good match : " << (int)good_matches.size() << std::endl;
//-- Draw only "good" matches
if (!good_matches.empty()){
drawMatchPoints(img1,keypoints_img1,img2,keypoints_img2,good_matches);
}
else {
Debug::error("Flann Matcher : Pas de match");
cv::Mat img_matches;
drawMatches( img1, keypoints_img1, img2, keypoints_img2,
matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
cv::imshow( "No match", img_matches );
cv::waitKey(5000);
}
}
//BruteForce with sift or surf
else if (type_of_matcher=="BF"){
Debug::info("USING Matcher Brute Force");
bFmatcher.match(descriptor_img1,descriptor_img2,matches);
if (!matches.empty()){
std::nth_element(matches.begin(),//Initial position
matches.begin()+24, //Position of the sorted element
matches.end());//End position
matches.erase(matches.begin()+25,matches.end());
drawMatchPoints(img1,keypoints_img1,img2,keypoints_img2,matches);
//drawMatchPoints(img2,keypoints_img2,img1,keypoints_img1,matches);
}
else {
Debug::error("Brute Force matcher : Pas de match");
cv::Mat img_matches;
drawMatches( img1, keypoints_img1, img2, keypoints_img2,
matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
cv::imshow( "No match", img_matches );
cv::waitKey(5000);
}
}
您有什么建议或建议吗？
EDIT :我解决了我的问题。
我有一个 C++ 问题，因为我有两个类。一个是关于匹配，另一个是关于寻找关键特征。我已经写在我的 .h std::vector 上，描述符也是如此。
class keyFeatures{
public:
...
std::vector<keyPoint> keypoints;
...
我删除了这个属性，并做了一个接受参数 std::vector 关键点的函数
cv::Mat descriptor_img1 = keyfeatures.compute_Descriptors(img1,keypoints_img1);
代替
cv::Mat descriptor_img1 = keyfeatures.compute_Descriptors(img1);
我认为我进行匹配时发生了冲突...
但我不知道为什么我不必将其写在 .h 上并在我的函数上执行本地参数。
谢谢 ！
