make error: undefined reference to cpp_redis::client::set(..

Question

完整的错误堆栈跟踪:

undefined reference to `cv::Mat::Mat(int, int, int, void*, unsigned long)'
undefined reference to `cv::imencode(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, cv::_InputArray const&, std::vector<unsigned char, std::allocator<unsigned char> >&, std::vector<int, std::allocator<int> > const&)'
undefined reference to `cpp_redis::client::client()'
undefined reference to `cpp_redis::client::connect(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned long, std::function<void (std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned long, cpp_redis::connect_state)> const&, unsigned int, int, unsigned int)'
undefined reference to `cpp_redis::client::set(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)'
undefined reference to `cpp_redis::client::sync_commit()'
undefined reference to `cpp_redis::client::~client()'
undefined reference to `cv::Mat::~Mat()'
undefined reference to `cpp_redis::client::~client()'
undefined reference to `cv::Mat::~Mat()'
collect2: error: ld returned 1 exit status
src/sensors/camera/camera/CMakeFiles/sample_camera.dir/build.make:130: recipe for target 'src/sensors/camera/camera/sample_camera' failed
make[2]: *** [src/sensors/camera/camera/sample_camera] Error 1
CMakeFiles/Makefile2:2246: recipe for target 'src/sensors/camera/camera/CMakeFiles/sample_camera.dir/all' failed
make[1]: *** [src/sensors/camera/camera/CMakeFiles/sample_camera.dir/all] Error 2
Makefile:149: recipe for target 'all' failed
make: *** [all] Error 2

下面是导致make失败的代码片段:

std::vector<uchar> buf; 
cv::Mat matImage = cv::Mat(imgCPU->prop.width, imgCPU->prop.height, CV_8UC3, imgCPU->data[0]);
cv::imencode(".jpg", matImage, buf);

cpp_redis::client client;
client.connect();
client.set("image", {buf.begin(), buf.end()});
client.sync_commit();

注意imgCPU->prop.width, imgCPU->prop.height为整型和

imgCPU->data[0]为uint8_t *。

我应该在CMakeLists.txt文件中做什么更改才能使我的程序正确编译?

下面是我的CMakeLists.txt文件的样子:

project(sample_camera C CXX)
pkg_check_modules(OPENCV opencv)
if(${OPENCV_FOUND})
MESSAGE("OPENCV_FOUND:" ${OPENCV_FOUND})
MESSAGE("OPENCV_VERSION:" ${OPENCV_VERSION})
MESSAGE("OPENCV_LIBRARIES:" ${OPENCV_LIBRARIES})
MESSAGE("OPENCV_INCLUDE_DIRS:" ${OPENCV_INCLUDE_DIRS})
MESSAGE("OPENCV_LIBRARY_DIRS:" ${OPENCV_LIBRARY_DIRS})
INCLUDE_DIRECTORIES(${OPENCV_INCLUDE_DIRS})
INCLUDE_DIRECTORIES("/usr/include/opencv4")
INCLUDE_DIRECTORIES("/usr/include/opencv4/opencv2")
LINK_DIRECTORIES(${OPENCV_LIBRARY_DIRS})
LINK_DIRECTORIES("/usr/include/opencv4/opencv2")
endif()
#-------------------------------------------------------------------------------
# Project files
#-------------------------------------------------------------------------------
set(PUBLIC_DOCS
README.md
)
set(SOURCES
main.cpp
)
set(LIBRARIES
${Driveworks_LIBRARIES}
samples_framework
lodepng-src
)
#-------------------------------------------------------------------------------
# Final target
#-------------------------------------------------------------------------------
add_executable(${PROJECT_NAME} ${SOURCES})
target_link_libraries(${PROJECT_NAME} PRIVATE ${LIBRARIES})
set_property(TARGET ${PROJECT_NAME} PROPERTY FOLDER "Samples")
# ------------------------------------------------------------------------------
# Install target
# ------------------------------------------------------------------------------
sdk_add_sample(${PROJECT_NAME})
sdk_add_sample_data(${PROJECT_NAME} "samples/sensors/camera/camera")

Answer 1

你的CMakeLists.txt是错误的和混乱的，试试这个:

cmake_minimum_required(VERSION 3.16)
project(DisplayImage CXX)
find_package(OpenCV REQUIRED COMPONENTS core imgproc video)
...
add_executable(${PROJECT_NAME} ${SOURCES})
target_link_libraries(${PROJECT_NAME} 
PRIVATE
opencv_core 
opencv_video
opencv_imgproc)

删除INCLUDE_DIRECTORIES和LINK_DIRECTORIES，因为它们在现代CMake中已经过时(错误)。