我的代码包括一个部分,其中我会对一组匹配进行排序,并根据距离定义好的匹配项。当我尝试绘制这些匹配项时,出现了错误:
OpenCV Error: Assertion failed (i1 >= 0 && i1 < static_cast<int>(keypoints1.size())) in drawMatches, file /home/user/OpenCV/opencv-2.4.10/modules/features2d/src/draw.cpp, line 207
terminate called after throwing an instance of 'cv::Exception'
what(): /home/user/OpenCV/opencv-2.4.10/modules/features2d/src/draw.cpp:207: error: (-215) i1 >= 0 && i1 < static_cast<int>(keypoints1.size()) in function drawMatches
draw.cpp文件显示:
// draw matches
for( size_t m = 0; m < matches1to2.size(); m++ )
{
if( matchesMask.empty() || matchesMask[m] )
{
int i1 = matches1to2[m].queryIdx;
int i2 = matches1to2[m].trainIdx;
CV_Assert(i1 >= 0 && i1 < static_cast<int>(keypoints1.size()));
CV_Assert(i2 >= 0 && i2 < static_cast<int>(keypoints2.size()));
const KeyPoint &kp1 = keypoints1[i1], &kp2 = keypoints2[i2];
_drawMatch( outImg, outImg1, outImg2, kp1, kp2, matchColor, flags );
}
}
我的drawMatches调用如下:
Mat matchesImage;
drawMatches( im1, keypoints1, im2, keypoints2,
good_matches, matchesImage, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
有人能帮我解释一下这个错误吗?
更新:
这是我的good_matches计算代码:
double min_dist = 10000;
double max_dist = 0;
//-- Quick calculation of max and min distances between keypoints
for( int i = 0; i < descriptors1.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
std::vector< DMatch > good_matches;
for( int i = 0; i < descriptors1.rows; i++ ) {
if( matches[i].distance <= max(2*min_dist, 0.02) ) {
good_matches.push_back( matches[i]);
}
}
for( int i = 0; i < (int)good_matches.size(); i++ ) {
printf( "-- Good Match [%d] Keypoint 1: %d -- Keypoint 2: %d \n",
i, good_matches[i].queryIdx, good_matches[i].trainIdx );
}
cout << "number of good matches: " << (int)good_matches.size() << endl;;
//Draw matches and save file
Mat matchesImage;
drawMatches( im1, keypoints1, im2, keypoints2,
good_matches, matchesImage, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
更新2:
BFMatcher matcher(NORM_L2, true);
vector<DMatch> matches;
matcher.match(descriptors1, descriptors2, matches);