我使用Sift/Surf和ORB,但有时候在使用drawMatch函数时会出现问题。
以下是错误信息:
OpenCV错误:在drawMatches函数中断言失败(i2 >= 0 && i2 < static_cast(keypoints2.size())),文件/home/opencv-2.4.6.1/modules/features2d/src/draw.cpp,第208行
终止程序并抛出'cv::Exception'实例
具体代码如下:
我尝试将img1、keypoints_img1与img2和keypoints_img2反转,如下所示:
匹配部分:
代替
以下是错误信息:
OpenCV错误:在drawMatches函数中断言失败(i2 >= 0 && i2 < static_cast(keypoints2.size())),文件/home/opencv-2.4.6.1/modules/features2d/src/draw.cpp,第208行
终止程序并抛出'cv::Exception'实例
具体代码如下:
drawMatchPoints(img1,keypoints_img1,img2,keypoints_img2,matches);
我尝试将img1、keypoints_img1与img2和keypoints_img2反转,如下所示:
drawMatchPoints(img2,keypoints_img2,img1,keypoints_img1,matches);
针对我正在执行单应性的功能:
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);
但我仍然出现了错误!
我注意到当我的keypoints_img1的大小小于keypoints_img2的大小时,就会出现错误:
keyPoint1的大小:244 - keyPoint2的大小:400
所以如果我交换两张图片的加载顺序,那么它可以工作,但我无法预先知道我的第一张图片是否比第二张图片具有更多的关键点...
我的代码(最重要的步骤)是为了创建特征:
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 );
匹配部分:
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);
}
}
你有任何建议或意见吗?
编辑:我解决了我的问题。 我有一个c++问题,因为我有两个类。一个是关于匹配的,另一个是关于查找关键特征点的。我在我的.h文件中写了std::vector和描述符。
class keyFeatures{
public:
...
std::vector<keyPoint> keypoints;
...
我删除了这个属性,然后编写了一个函数,它以std::vector keypoints作为参数。
cv::Mat descriptor_img1 = keyfeatures.compute_Descriptors(img1,keypoints_img1);
代替
cv::Mat descriptor_img1 = keyfeatures.compute_Descriptors(img1);
我认为当我进行匹配时出现了冲突...但我不知道为什么我不必在我的.h文件中书写它,并在我的函数中使用局部参数。
谢谢!