错误:未定义对‘`cv::imread(std::string const&，int)’的引用

Question

我是Qt的新手，我有一个项目需要在Qt中配置OpenCV，我试图在Qt中运行一个简单的代码，但我得到了这个错误“未定义的对cv::imread(std::string const&, int)的引用”，这是我的代码...

#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"

using namespace cv;

int main(){
Mat src,gray;
src=imread("C:/Users/user/Desktop/wood-pattern.png",1);
imshow("gg",src);
cvWaitKey(0);
return 0;
}

我的source.pro是

#-------------------------------------------------
#
# Project created by QtCreator 2014-08-24T20:38:56
#
#-------------------------------------------------
INCLUDEPATH += C:\opencv\opencv2.4.9\build\include\
CONFIG(release,debug|release)
{
LIBS += C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_calib3d249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_contrib249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_core249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_features2d249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_flann249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_gpu249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_highgui249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_imgproc249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_legacy249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_ml249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_objdetect249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_ts249.lib \
        C:\opencv\opencv2.4.9\build\x86\vc11\lib\opencv_video249.lib
        }
CONFIG(debug,debug|release)
       {
LIBS += C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_calib3d249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_contrib249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_core249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_features2d249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_flann249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_gpu249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_highgui249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_imgproc249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_legacy249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_ml249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_objdetect249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_ts249.lib \
        C:\opencv\opencv2.4.9\build\x64\vc11\lib\opencv_video249.lib \
}
QT       += core

QT       -= gui

TARGET = Source
CONFIG   += console
CONFIG   -= app_bundle

TEMPLATE = app


SOURCES += main.cpp

我看到了所有关于的答案，但它们都不起作用。我的Qt是32位，我的Windows是64位。我想我的配置是错误的。我遵循了很多教程，但它们不是针对OpenCV 2.4.9的，所以请帮助我……

Answer 1

查看pkg-config opencv --libs的输出，找出缺少的库，然后将它们添加到配置中。

对我来说，完整的库列表是

/usr/lib64/libopencv_calib3d.so.2.4.8
/usr/lib64/libopencv_contrib.so.2.4.8
/usr/lib64/libopencv_core.so.2.4.8
/usr/lib64/libopencv_features2d.so.2.4.8
/usr/lib64/libopencv_flann.so.2.4.8
/usr/lib64/libopencv_gpu.so.2.4.8
/usr/lib64/libopencv_highgui.so.2.4.8
/usr/lib64/libopencv_imgproc.so.2.4.8
/usr/lib64/libopencv_legacy.so.2.4.8
/usr/lib64/libopencv_ml.so.2.4.8
/usr/lib64/libopencv_nonfree.so.2.4.8    # you don't have this one
/usr/lib64/libopencv_objdetect.so.2.4.8
/usr/lib64/libopencv_photo.so.2.4.8      # this one
/usr/lib64/libopencv_stitching.so.2.4.8  # this one
/usr/lib64/libopencv_superres.so.2.4.8   # and this one
/usr/lib64/libopencv_ts.a
/usr/lib64/libopencv_video.so.2.4.8

Answer 2

对Windows一无所知，但如果它有pkg-config，你应该能够让QMake自动使用它，只需添加

PKGCONFIG += opencv

添加到您的项目文件中(假设您的OpenCV安装了正确的软件包配置文件，就像在正常的平台上一样)。

Answer 3

在我的例子中，它仅仅是参数的顺序，请注意

g++ main.cpp -o main `pkg-config --libs --cflags opencv`

工作时

g++ -o main `pkg-config --libs --cflags opencv` main.cpp

没有，因为后者在引用 main.cpp之前定义了main.cpp需要的内容。