c++ - OPENCV 错误 : undefined reference to "cvLoadImage"

Question

我有两个文件:

测试.cpp :

#include "highgui.h"
#include <cv.h>
int main( int argc, char** argv ) {
    IplImage* img = cvLoadImage( argv[1] );
    cvNamedWindow( "Example1", CV_WINDOW_AUTOSIZE );
    cvShowImage( "Example1", img );
    cvWaitKey(0);
    cvReleaseImage( &img );
    cvDestroyWindow( "Example1" );
}

CMakeLists.txt:

cmake_minimum_required(VERSION 2.8)
set(CMAKE_MODULE_PATH ${/home/jinder1s/Documents/project/opencv/FindOpenCV.make} )
project(hello)
Find_package (OpenCV REQUIRED)
if(OpenCV_FOUND)
    add_executable (Hello test.cpp)
    find_library(Opencv_lib 
    NAMES opencv_core opencv_highgui opencv_imgproc
    PATHS /usr/local/lib)
endif()

这是我得到的模板。

jinder1s@jinder1s-lat-lap:~/Documents/project/opencv/tests$ cmake .
-- Configuring done
-- Generating done
-- Build files have been written to: /home/jinder1s/Documents/project/opencv/tests
jinder1s@jinder1s-lat-lap:~/Documents/project/opencv/tests$ make
Linking CXX executable Hello
CMakeFiles/Hello.dir/test.cpp.o: In function `main':
test.cpp:(.text+0x1d): undefined reference to `cvLoadImage'
test.cpp:(.text+0x35): undefined reference to `cvNamedWindow'
test.cpp:(.text+0x49): undefined reference to `cvShowImage'
test.cpp:(.text+0x55): undefined reference to `cvWaitKey'
test.cpp:(.text+0x61): undefined reference to `cvReleaseImage'
test.cpp:(.text+0x6d): undefined reference to `cvDestroyWindow'
collect2: error: ld returned 1 exit status
make[2]: *** [Hello] Error 1
make[1]: *** [CMakeFiles/Hello.dir/all] Error 2
make: *** [all] Error 2

我刚开始学习 opencv，因为这是我的第一个代码，但我似乎无法让它工作。我真的可以在这里使用一些帮助。看不出我做错了什么。

Answer 1

在检查库是否可用后，您必须告诉 cmake 链接库。

像 target_link_libraries( Hello ${OpenCV_LIBS} ) 就在你的 endif() 之前

参见 http://www.cmake.org/cmake/help/cmake_tutorial.html了解如何使用 CMake，以及 http://docs.opencv.org/doc/tutorials/introduction/linux_gcc_cmake/linux_gcc_cmake.html用于带有 openCV 的 CMake。

您可以通过键入“make VERBOSE=1”来检查您的链接器是如何被调用的。它有助于调试 cmake 文件。