兩個 OpenCV 版本：更新到一個破壞了另一個，儘管它們應該是分開的

大約一周前，我的 Linux 發行版（Antergos）從儲存庫（版本 3.14.1）安裝了最新版本的 OpenCV。為了兼容性，我將 OpenCV 2（版本 2.4.13.5）安裝在我的主目錄的單獨文件夾中。

為了使用 g++ 更輕鬆地進行編譯，我在 .bashrc 文件中為每個版本創建了別名。這個配置基本上允許我編譯，比如說一個只有 main.cpp 文件的程序，使用g++ main.cpp $(opencv2)下面是我的 .bashrc 文件中的相關程式碼：

# Programming Related Aliases
# OpenCV
alias opencv3='pkg-config --cflags --libs opencv' # OpenCV 3
opencv2prefix="$HOME/separate-libs/opencv2/release/installed"   # Prefix that serves as the basis for the pathname of the OpenCV 2 directory.
export PKG_CONFIG_PATH="$opencv2prefix/lib/pkgconfig"
export LD_LIBRARY_PATH="$opencv2prefix/lib"
alias opencv2="pkg-config --cflags --libs opencv2"  # OpenCV 2 lib, include and runtime specifications for OpenCV 2. Defined in PKG_CONFIG_PATH.

直到今天早些時候，當我使用 OpenCV 2 配置編譯一個更大的程序（執行圖像分割）時，這個設置才完美執行。起初我以為我在從原始碼編譯 OpenCV 2 時忘記了一個必要的建構選項。然而，為了檢查我的理智，我嘗試編譯一個在上述更新之前用 OpenCV 2 成功編譯的程序。結果如下：

/usr/bin/ld: warning: libImath-2_2.so.12, needed by /home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so, not found (try using -rpath or -rpath-link)
/usr/bin/ld: warning: libIlmImf-2_2.so.22, needed by /home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so, not found (try using -rpath or -rpath-link)
/usr/bin/ld: warning: libIex-2_2.so.12, needed by /home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so, not found (try using -rpath or -rpath-link)
/usr/bin/ld: warning: libHalf.so.12, needed by /home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so, not found (try using -rpath or -rpath-link)
/usr/bin/ld: warning: libIlmThread-2_2.so.12, needed by /home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so, not found (try using -rpath or -rpath-link)
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::globalThreadCount()'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::ChannelList::insert(char const*, Imf_2_2::Channel const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::InputFile::header() const'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::hasChromaticities(Imf_2_2::Header const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::OutputFile::writePixels(int)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::InputFile::setFrameBuffer(Imf_2_2::FrameBuffer const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::InputFile::readPixels(int, int)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Channel::Channel(Imf_2_2::PixelType, int, int, bool)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Slice::Slice(Imf_2_2::PixelType, char*, unsigned long, unsigned long, int, int, double, bool, bool)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::OutputFile::setFrameBuffer(Imf_2_2::FrameBuffer const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Header::dataWindow() const'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Header::channels()'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `half::_eLut'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Header::channels() const'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Header::~Header()'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Header::Header(int, int, float, Imath_2_2::Vec2<float> const&, float, Imf_2_2::LineOrder, Imf_2_2::Compression)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::InputFile::InputFile(char const*, int)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::OutputFile::OutputFile(char const*, Imf_2_2::Header const&, int)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::FrameBuffer::insert(char const*, Imf_2_2::Slice const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::ChannelList::findChannel(char const*) const'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::chromaticities(Imf_2_2::Header const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `half::convert(int)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::Chromaticities::Chromaticities(Imath_2_2::Vec2<float> const&, Imath_2_2::Vec2<float> const&, Imath_2_2::Vec2<float> const&, Imath_2_2::Vec2<float> const&)'
/home/kvasir/separate-libs/opencv2/release/installed/lib/libopencv_highgui.so: undefined reference to `Imf_2_2::OutputFile::~OutputFile()'
collect2: error: ld returned 1 exit status

我試過執行sudo ldconfig，以及檢查我的路徑名是否正確。另外，我檢查了所有文件的包含語句中的兼容性問題，沒有發現任何問題。我假設包管理器對 OpenCV 3 安裝的更新搞砸了一切。但如果是這樣，為什麼呢？顯然，如果 OpenCV 安裝在同一個文件夾中，我可以理解。但他們倆似乎完全分開，彼此不了解。我唯一的其他猜測是 pkg-config。

當我嘗試編譯包含目標文件和更複雜程式碼的圖像分割程序時，我得到：

/tmp/ccpvnIWK.o: In function `main':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/main.cpp:37: undefined reference to `cv::waitKey(int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/main.cpp:51: undefined reference to `cv::Mat::convertTo(cv::_OutputArray const&, int, double, double) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/main.cpp:74: undefined reference to `cv::imwrite(cv::String const&, cv::_InputArray const&, std::vector<int, std::allocator<int> > const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/main.cpp:75: undefined reference to `cv::namedWindow(cv::String const&, int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/main.cpp:76: undefined reference to `cv::imshow(cv::String const&, cv::_InputArray const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/main.cpp:77: undefined reference to `cv::waitKey(int)'
/tmp/ccpvnIWK.o: In function `cv::String::String(char const*)':
/usr/include/opencv2/core/cvstd.hpp:602: undefined reference to `cv::String::allocate(unsigned long)'
/tmp/ccpvnIWK.o: In function `cv::String::~String()':
/usr/include/opencv2/core/cvstd.hpp:648: undefined reference to `cv::String::deallocate()'
/tmp/ccpvnIWK.o: In function `cv::String::operator=(cv::String const&)':
/usr/include/opencv2/core/cvstd.hpp:656: undefined reference to `cv::String::deallocate()'
/tmp/ccpvnIWK.o: In function `cv::Mat::Mat(cv::Mat const&)':
/usr/include/opencv2/core/mat.inl.hpp:490: undefined reference to `cv::Mat::copySize(cv::Mat const&)'
/tmp/ccpvnIWK.o: In function `cv::Mat::~Mat()':
/usr/include/opencv2/core/mat.inl.hpp:704: undefined reference to `cv::fastFree(void*)'
/tmp/ccpvnIWK.o: In function `cv::Mat::release()':
/usr/include/opencv2/core/mat.inl.hpp:816: undefined reference to `cv::Mat::deallocate()'
/tmp/ccpvnIWK.o: In function `cv::Mat::operator=(cv::Mat&&)':
/usr/include/opencv2/core/mat.inl.hpp:1383: undefined reference to `cv::fastFree(void*)'
/tmp/ccpvnIWK.o: In function `cv::String::String(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
/usr/include/opencv2/core/cvstd.inl.hpp:83: undefined reference to `cv::String::allocate(unsigned long)'
Loader.o: In function `void cv::operator>><std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >(cv::FileNode const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&)':
/usr/include/opencv2/core/cvstd.inl.hpp:156: undefined reference to `cv::read(cv::FileNode const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)'
Loader.o: In function `Loader::loadControlParameters(ControlParameters&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:16: undefined reference to `cv::FileStorage::FileStorage(cv::String const&, int, cv::String const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:17: undefined reference to `cv::FileStorage::isOpened() const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:20: undefined reference to `cv::waitKey(int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:24: undefined reference to `cv::FileStorage::operator[](char const*) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:25: undefined reference to `cv::FileStorage::operator[](char const*) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:26: undefined reference to `cv::FileStorage::operator[](char const*) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:27: undefined reference to `cv::FileStorage::operator[](char const*) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:16: undefined reference to `cv::FileStorage::~FileStorage()'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:16: undefined reference to `cv::FileStorage::~FileStorage()'
Loader.o: In function `Loader::loadOriginalImage(ControlParameters const&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/Loader.cpp:35: undefined reference to `cv::imread(cv::String const&, int)'
Loader.o: In function `void cv::operator>><int>(cv::FileNode const&, int&)':
/usr/include/opencv2/core/persistence.hpp:1238: undefined reference to `cv::read(cv::FileNode const&, int&, int)'
MeanShift.o: In function `cv::operator*=(cv::Mat&, double const&)':
/usr/include/opencv2/core/operations.hpp:254: undefined reference to `cv::Mat::convertTo(cv::_OutputArray const&, int, double, double) const'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:22: undefined reference to `cv::Mat::convertTo(cv::_OutputArray const&, int, double, double) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:24: undefined reference to `cv::cvtColor(cv::_InputArray const&, cv::_OutputArray const&, int, int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:26: undefined reference to `cv::split(cv::Mat const&, cv::Mat*)'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:28: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:29: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingLAB(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:30: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:32: undefined reference to `cv::merge(cv::Mat const*, unsigned long, cv::_OutputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:44: undefined reference to `cv::Mat::convertTo(cv::_OutputArray const&, int, double, double) const'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:46: undefined reference to `cv::cvtColor(cv::_InputArray const&, cv::_OutputArray const&, int, int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:48: undefined reference to `cv::split(cv::Mat const&, cv::Mat*)'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:50: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:51: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingHLS(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:52: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:54: undefined reference to `cv::merge(cv::Mat const*, unsigned long, cv::_OutputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingRGB(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:74: undefined reference to `cv::countNonZero(cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::segmentUsingRGB(cv::Mat, unsigned int)':
/usr/include/opencv2/core.hpp:788: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::segmentUsingRGB(cv::Mat, unsigned int)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:121: undefined reference to `cv::normalize(cv::_InputArray const&, cv::_InputOutputArray const&, double, double, int, int, cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::segmentFromFeatureSpace(cv::Mat const&, unsigned int, std::vector<SWin, std::allocator<SWin> > const&, std::vector<std::vector<cv::Point3_<int>, std::allocator<cv::Point3_<int> > >, std::allocator<std::vector<cv::Point3_<int>, std::allocator<cv::Point3_<int> > > > > const&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:145: undefined reference to `cv::split(cv::Mat const&, cv::Mat*)'
MeanShift.o: In function `MeanShift::getChannelsRanges(cv::Mat, int*, SImgDims&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:204: undefined reference to `cv::split(cv::Mat const&, cv::Mat*)'
MeanShift.o: In function `MeanShift::getChannelsRanges(cv::Mat, int*, SImgDims&)':
/usr/include/opencv2/core.hpp:819: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::getChannelsRanges(cv::Mat, int*, SImgDims&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:214: undefined reference to `cv::minMaxLoc(cv::_InputArray const&, double*, double*, cv::Point_<int>*, cv::Point_<int>*, cv::_InputArray const&)'
MeanShift.o: In function `MeanShift::showImage(cv::Mat, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:789: undefined reference to `cv::namedWindow(cv::String const&, int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:795: undefined reference to `cv::imshow(cv::String const&, cv::_InputArray const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:797: undefined reference to `cv::waitKey(int)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:800: undefined reference to `cv::destroyWindow(cv::String const&)'
MeanShift.o: In function `MeanShift::makeIt8bit(cv::Mat)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:811: undefined reference to `cv::Mat::convertTo(cv::_OutputArray const&, int, double, double) const'
MeanShift.o: In function `MeanShift::standardization(cv::Mat const&)':
/usr/include/opencv2/core.hpp:819: undefined reference to `cv::noArray()'
MeanShift.o: In function `MeanShift::standardization(cv::Mat const&)':
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:827: undefined reference to `cv::minMaxLoc(cv::_InputArray const&, double*, double*, cv::Point_<int>*, cv::Point_<int>*, cv::_InputArray const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:829: undefined reference to `cv::operator-(cv::Mat const&, cv::Scalar_<double> const&)'
/home/kvasir/Documents/PolytechSchoolWork/2018 Spring (algorithms, software engineering, computer vision, artificial intelligence, computer architecture and organization)/computer-vision/projects/3rd-assignment/MeanShift/MeanShift.cpp:829: undefined reference to `cv::operator*(cv::MatExpr const&, double)'
MeanShift.o: In function `cv::Mat::Mat(int, int const*, int)':
/usr/include/opencv2/core/mat.inl.hpp:446: undefined reference to `cv::Mat::create(int, int const*, int)'
MeanShift.o: In function `cv::Mat::Mat(int, int const*, int, cv::Scalar_<double> const&)':
/usr/include/opencv2/core/mat.inl.hpp:454: undefined reference to `cv::Mat::create(int, int const*, int)'
/usr/include/opencv2/core/mat.inl.hpp:455: undefined reference to `cv::Mat::operator=(cv::Scalar_<double> const&)'
MeanShift.o: In function `cv::Mat::create(int, int, int)':
/usr/include/opencv2/core/mat.inl.hpp:796: undefined reference to `cv::Mat::create(int, int const*, int)'
collect2: error: ld returned 1 exit status
make: *** [makefile:6: segmentation] Error 1

這個輸出特別讓我感到奇怪的是，*.o 文件似乎在/usr/include/opencv2尋找函式定義。如果它是用 呼叫的$opencv2，它不應該查看/home/kvasir/separate-libs/opencv2/release/installed/*嗎？

產生上述錯誤的makefile如下所示：

segmentation : main.cpp Loader.o MeanShift.o ControlParameters.h defs.h
   g++ -g -o segmentation main.cpp Loader.o MeanShift.o $(opencv2)

Loader.o : Loader.cpp Loader.h
   g++ -g -c Loader.cpp

MeanShift.o : MeanShift.cpp MeanShift.h
   g++ -g -c MeanShift.cpp

clean:
   rm segmentation *.o

我還嘗試使用 OpenCV 2 版本編譯目標文件，但無濟於事。我的下一步可能是重新安裝 OpenCV 2。但是，我很好奇為什麼會發生這種情況，以及將來是否有任何方法可以解決和防止這種情況發生。

此外，這兩個程序都可以使用 OpenCV 3 成功編譯，沒有問題。例如，將$(opencv2)上面的 makefile 更改為 $(opencv3) 不會導致錯誤和工作程序。

編輯：我是一名大學生，這些程序是電腦科學課程的作業。上面提到的比較複雜的程序不是我寫的。它是我的教授提供的，是從另一所大學借來的。我必須修改它，但它處於可編譯狀態，除了 main.cpp 中的 main 是 void 的一個例外。我將其更改為 int 並進行了 return 語句return 0;，它似乎與 OpenCV 3 編譯得非常好。

**注意：**我知道這兩個程序的程式碼都有效。我不是在尋求編碼方面的幫助，而是在問為什麼對 OpenCV 3 安裝的更新/usr/include/會在單獨的位置破壞 OpenCV 2 的自定義安裝。

編輯：這是更複雜（圖像分割）程序的連結。

編輯：我已將更簡單程序的原始碼上傳到 Google Drive。它可以在這裡找到。

我已經解決了我面臨的問題。一個我不確定。另一個是我自己無知的結果。至於我在使用 OpenCV 2 和兩個程序中更簡單的程序時遇到的奇怪編譯錯誤，我不確定。但是，重新編譯 OpenCV 2 似乎已經解決了這個問題。

我犯的最大錯誤是我的makefile。我不知道 .bashrc 中定義的別名不會轉換為 makefile，並且與 bash 相比，makefile 的語法略有不同。在 bash$(opencv2)呼叫中，命令 opencv2 引用並在目前命令中使用其輸出。Using$opencv2將引用一個變數並返回它的值。在 makefile 中，情況並非如此。實際上，$(opencv2)返回一個名為 opencv2 的本地定義變數的值。命令可以由這些變數定義，但必須用反引號/嚴重標記包圍。下面是我更正的makefile：

OPENCV=`pkg-config --cflags --libs opencv2`
segmentation : main.cpp Loader.o MeanShift.o ControlParameters.h defs.h
        g++ -g main.cpp Loader.o MeanShift.o $(OPENCV) -o segmentation      

Loader.o : Loader.cpp Loader.h
        g++ -g -c Loader.cpp $(OPENCV)

MeanShift.o : MeanShift.cpp MeanShift.h
        g++ -g -c MeanShift.cpp $(OPENCV)

clean:
        rm segmentation *.o

引用自：https://unix.stackexchange.com/questions/432476