我正在尝试编译一个包含libuvc.h头文件和一些opencv2头文件的C ++程序。
问题是，我收到以下错误（未完成的引用）：
root@Raspi_DataHarvest:~/Schreibtisch# g++ UVCCameraHandler.cpp -I/usr/local/include/libuvc -I/usr/local/include/opencv2
/tmp/ccvQZdkd.o: In function `UVCCameraHandler::start(int, CameraProperties, int)':
UVCCameraHandler.cpp:(.text+0x164): undefined reference to `uvc_init'
UVCCameraHandler.cpp:(.text+0x184): undefined reference to `uvc_perror'
UVCCameraHandler.cpp:(.text+0x204): undefined reference to `uvc_get_device_descriptor'
UVCCameraHandler.cpp:(.text+0x334): undefined reference to `uvc_open'
UVCCameraHandler.cpp:(.text+0x354): undefined reference to `uvc_perror'
UVCCameraHandler.cpp:(.text+0x3a8): undefined reference to `uvc_get_stream_ctrl_format_size'
UVCCameraHandler.cpp:(.text+0x3e8): undefined reference to `uvc_get_stream_ctrl_format_size'
UVCCameraHandler.cpp:(.text+0x40c): undefined reference to `uvc_print_diag'
UVCCameraHandler.cpp:(.text+0x424): undefined reference to `uvc_print_stream_ctrl'
UVCCameraHandler.cpp:(.text+0x43c): undefined reference to `uvc_perror'
UVCCameraHandler.cpp:(.text+0x46c): undefined reference to `uvc_stream_open_ctrl'
UVCCameraHandler.cpp:(.text+0x48c): undefined reference to `uvc_stream_start_iso'
UVCCameraHandler.cpp:(.text+0x4a4): undefined reference to `uvc_perror'
/tmp/ccvQZdkd.o: In function `UVCCameraHandler::grabFramesGrayscale(cv::Mat&, cv::Mat&)':
UVCCameraHandler.cpp:(.text+0x5c8): undefined reference to `uvc_stream_get_frame'
/tmp/ccvQZdkd.o: In function `UVCCameraHandler::grabFramesColor(cv::Mat&, cv::Mat&)':
UVCCameraHandler.cpp:(.text+0x864): undefined reference to `uvc_stream_get_frame'
UVCCameraHandler.cpp:(.text+0x92c): undefined reference to `cv::cvtColor(cv::_InputArray const&, cv::_OutputArray const&, int, int)'
/tmp/ccvQZdkd.o: In function `UVCCameraHandler::uvcFindDevice(uvc_context*, uvc_device**, int, int, char const*, int)':
UVCCameraHandler.cpp:(.text+0xae0): undefined reference to `uvc_get_device_list'
UVCCameraHandler.cpp:(.text+0xb10): undefined reference to `uvc_get_device_descriptor'
UVCCameraHandler.cpp:(.text+0xd0c): undefined reference to `uvc_get_device_descriptor'
/tmp/ccvQZdkd.o: In function `UVCCameraHandler::setProperties(CameraProperties)':
UVCCameraHandler.cpp:(.text+0xfb0): undefined reference to `uvc_get_gain'
UVCCameraHandler.cpp:(.text+0xff8): undefined reference to `uvc_set_gain'
UVCCameraHandler.cpp:(.text+0x103c): undefined reference to `uvc_set_ae_mode'
UVCCameraHandler.cpp:(.text+0x1050): undefined reference to `uvc_set_exposure_abs'
UVCCameraHandler.cpp:(.text+0x1068): undefined reference to `uvc_set_ae_mode'
/tmp/ccvQZdkd.o: In function `cv::String::String(char const*)':
UVCCameraHandler.cpp:(.text._ZN2cv6StringC2EPKc[_ZN2cv6StringC5EPKc]+0x60): undefined reference to `cv::String::allocate(unsigned int)'
/tmp/ccvQZdkd.o: In function `cv::String::~String()':
UVCCameraHandler.cpp:(.text._ZN2cv6StringD2Ev[_ZN2cv6StringD5Ev]+0x14): undefined reference to `cv::String::deallocate()'
/tmp/ccvQZdkd.o: In function `cv::String::operator=(cv::String const&)':
UVCCameraHandler.cpp:(.text._ZN2cv6StringaSERKS0_[_ZN2cv6StringaSERKS0_]+0x30): undefined reference to `cv::String::deallocate()'
/tmp/ccvQZdkd.o: In function `cv::Mat::Mat(cv::Size_<int>, int, void*, unsigned int)':
UVCCameraHandler.cpp:(.text._ZN2cv3MatC2ENS_5Size_IiEEiPvj[_ZN2cv3MatC5ENS_5Size_IiEEiPvj]+0x140): undefined reference to `cv::error(int, cv::String const&, char const*, char const*, int)'
UVCCameraHandler.cpp:(.text._ZN2cv3MatC2ENS_5Size_IiEEiPvj[_ZN2cv3MatC5ENS_5Size_IiEEiPvj]+0x244): undefined reference to `cv::error(int, cv::String const&, char const*, char const*, int)'
/tmp/ccvQZdkd.o: In function `cv::Mat::~Mat()':
UVCCameraHandler.cpp:(.text._ZN2cv3MatD2Ev[_ZN2cv3MatD5Ev]+0x3c): undefined reference to `cv::fastFree(void*)'
/tmp/ccvQZdkd.o: In function `cv::Mat::operator=(cv::Mat const&)':
UVCCameraHandler.cpp:(.text._ZN2cv3MataSERKS0_[_ZN2cv3MataSERKS0_]+0x140): undefined reference to `cv::Mat::copySize(cv::Mat const&)'
/tmp/ccvQZdkd.o: In function `cv::Mat::create(int, int, int)':
UVCCameraHandler.cpp:(.text._ZN2cv3Mat6createEiii[_ZN2cv3Mat6createEiii]+0xc4): undefined reference to `cv::Mat::create(int, int const*, int)'
/tmp/ccvQZdkd.o: In function `cv::Mat::release()':
UVCCameraHandler.cpp:(.text._ZN2cv3Mat7releaseEv[_ZN2cv3Mat7releaseEv]+0x68): undefined reference to `cv::Mat::deallocate()'
/tmp/ccvQZdkd.o: In function `cv::Mat::operator()(cv::Rect_<int> const&) const':
UVCCameraHandler.cpp:(.text._ZNK2cv3MatclERKNS_5Rect_IiEE[_ZNK2cv3MatclERKNS_5Rect_IiEE]+0x24): undefined reference to `cv::Mat::Mat(cv::Mat const&, cv::Rect_<int> const&)'
collect2: error: ld returned 1 exit status
所以，这看起来像g ++没有找到头文件的位置，但是它们安装在正确的目录中！
root@Raspi_DataHarvest:~# find / | grep libuvc.h
/usr/local/include/libuvc/libuvc.h
root@Raspi_DataHarvest:~# find / | grep opencv2/opencv.hpp
/usr/local/include/opencv2/opencv.hpp
此外，使用绝对路径没有效果，例如：
#include "/usr/local/include/libuvc.h"
...
有谁知道如何解决参考错误？
答案 0 :(得分：2)
尝试
g++ UVCCameraHandler.cpp -I/usr/local/include/libuvc -I/usr/local/include/opencv2 -luvc -lopencv
最优选的
g++ UVCCameraHandler.cpp `pkg-config --libs --cflags opencv` `pkg-config --libs --cflags lubuvc`
答案 1 :(得分：2)
构建C ++程序分为三个步骤：
现代编译器经常使用前端程序（例如GCC和g++程序）将步骤2和3组合成一个动作。
在上面的步骤2中，包含了头文件。
在第3步中，您需要链接与实际的库。你没有这样做，所以链接器会抱怨它无法找到你使用的功能。
使用GCC链接库是使用-l（小写L）选项，列出库名称。例如，-lopencv与OpenCV库链接。
如果库位于非标准位置（通常为/usr/local/lib），那么您需要告诉链接器在哪里找到库。这是通过-L选项完成的，类似于您已用于告诉编译器在何处搜索头文件的-I选项。例如-L/usr/local/lib。
答案 2 :(得分：1)
您需要链接正确的库（假设您的库位于/usr/local/lib）：
g++ UVCCameraHandler.cpp -I/usr/local/include/libuvc -I/usr/local/include/opencv2 -L/usr/local/lib -luvc -lopencv_core