Question

我正在实现这个简单的例子，只是为了熟悉OpenCv和SIFT。

1  #include <opencv2/core/core.hpp>
2  #include <opencv2/features2d/features2d.hpp>
3  #include <opencv2/highgui/highgui.hpp>
4
5  using namespace std;
6 
7  int main(int argc, char** argv) {
8
9     const cv::Mat input = cv::imread("/tmp/image.jpg", 0); //Load as grayscale
10
11    cv::SiftFeatureDetector detector;
12    std::vector<cv::KeyPoint> keypoints;
13    detector.detect(input, keypoints);
14
15    // Add results to image and save.
16    cv::Mat output;
17    cv::drawKeypoints(input, keypoints, output);
18    cv::imwrite("/tmp/SIFT_RESULT.jpg", output);
19
20    return 0;
21
22 }

我期待它非常简单，但它会引发以下错误：

undefined reference to 'cv::SIFT::CommonParams::CommonParams()'第11行
undefined reference to 'cv::FeatureDetector::detect(cv::Mat const&, std::vector<cv::KeyPoint, std::allocator<cv::KeyPoint> >&, cv::Mat const&) const'
undefined reference to 'cv::drawKeypoints(cv::Mat const&, std::vector<cv::KeyPoint, std::allocator<cv::KeyPoint> > const&, cv::Mat&, cv::Scalar_<double> const&, int)'第17行

你能告诉我出了什么问题吗？这是代码中的问题，还是我错过了一些headers？

完成构建输出：

make all 
Building file: ../main.cpp
Invoking: GCC C++ Compiler
g++ -I/usr/local/include/opencv -I/usr/include/c++/4.5.2 -O0 -g3 -Wall -c -fmessage-length=0 -std=c++0x -MMD -MP -MF"main.d" -MT"main.d" -o "main.o" "../main.cpp"
Finished building: ../main.cpp

Building target: BioInfo
Invoking: GCC C++ Linker
g++ -L/usr/local/lib -o "BioInfo"  ./imageProcessingClass.o ./main.o   -lopencv_core -lopencv_highgui
./main.o: In function `main':
/.../Debug/../main.cpp:38: undefined reference to `cv::SIFT::CommonParams::CommonParams()'
/.../Debug/../main.cpp:38: undefined reference to `cv::SIFT::DetectorParams::DetectorParams()'
/.../Debug/../main.cpp:38: undefined reference to `cv::SiftFeatureDetector::SiftFeatureDetector(cv::SIFT::DetectorParams const&, cv::SIFT::CommonParams const&)'
/.../Debug/../main.cpp:40: undefined reference to `cv::FeatureDetector::detect(cv::Mat const&, std::vector<cv::KeyPoint, std::allocator<cv::KeyPoint> >&, cv::Mat const&) const'
/.../Debug/../main.cpp:44: undefined reference to `cv::drawKeypoints(cv::Mat const&, std::vector<cv::KeyPoint, std::allocator<cv::KeyPoint> > const&, cv::Mat&, cv::Scalar_<double> const&, int)'
./main.o: In function `~SiftFeatureDetector':
/usr/local/include/opencv2/features2d/features2d.hpp:1502: undefined reference to `vtable for cv::SiftFeatureDetector'
/usr/local/include/opencv2/features2d/features2d.hpp:1502: undefined reference to `cv::FeatureDetector::~FeatureDetector()'
collect2: ld returned 1 exit status
make: *** [BioInfo] Error 1

Build Finished

Answer 1

您似乎忘记了与OpenCV库的链接。还要记住，如果您要与OpenCV 2.4链接，那么有一个名为opencv_nonfree的“非自由”算法的新库，您需要链接到SIFT。

OpenCV上的简单SIFT检测器问题

1 个答案: