我使用Qt创建了一个简单的C ++项目，目标是从图像中提取一些连接的组件并将它们保存到适当的文件夹中。
我只使用一个.cpp文件和opencv来执行此操作。
但是当我运行程序时，我收到此错误：Symbol lookup error: undefined symbol: _ZN2cv6imreadERKSsi
说实话，我不明白发生了什么。我试着看一下人们遇到同样问题的一些帖子，但到目前为止没有任何工作。
我用ldd -d -r ./ExctractCC检查了一切似乎没问题：
linux-vdso.so.1 => (0x00007fffa23c4000)
libopencv_core.so.2.4 => /usr/lib/x86_64-linux-gnu/libopencv_core.so.2.4 (0x00007f3c5522c000)
libopencv_highgui.so.2.4 => /usr/lib/x86_64-linux-gnu/libopencv_highgui.so.2.4 (0x00007f3c54fe3000)
libopencv_imgproc.so.2.4 => /usr/lib/x86_64-linux-gnu/libopencv_imgproc.so.2.4 (0x00007f3c54b57000)
libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f3c547d5000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f3c544cc000)
libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f3c542b5000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f3c53eeb000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f3c53cd1000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f3c53ab3000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f3c538ab000)
libGL.so.1 => /usr/lib/x86_64-linux-gnu/mesa/libGL.so.1 (0x00007f3c53637000)
libtbb.so.2 => /usr/lib/x86_64-linux-gnu/libtbb.so.2 (0x00007f3c533f9000)
libjpeg.so.8 => /usr/lib/x86_64-linux-gnu/libjpeg.so.8 (0x00007f3c531a0000)
libpng12.so.0 => /lib/x86_64-linux-gnu/libpng12.so.0 (0x00007f3c52f7b000)
libtiff.so.5 => /usr/lib/x86_64-linux-gnu/libtiff.so.5 (0x00007f3c52d06000)
libjasper.so.1 => /usr/lib/x86_64-linux-gnu/libjasper.so.1 (0x00007f3c52ab1000)
libIlmImf-2_2.so.22 => /usr/lib/x86_64-linux-gnu/libIlmImf-2_2.so.22 (0x00007f3c525e3000)
libHalf.so.12 => /usr/lib/x86_64-linux-gnu/libHalf.so.12 (0x00007f3c5239f000)
libgtk-x11-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgtk-x11-2.0.so.0 (0x00007f3c51d54000)
libgdk-x11-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgdk-x11-2.0.so.0 (0x00007f3c51a9f000)
libgobject-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0 (0x00007f3c5184b000)
libglib-2.0.so.0 => /lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007f3c5153a000)
libgtkglext-x11-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libgtkglext-x11-1.0.so.0 (0x00007f3c51336000)
libgdkglext-x11-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libgdkglext-x11-1.0.so.0 (0x00007f3c510d1000)
libdc1394.so.22 => /usr/lib/x86_64-linux-gnu/libdc1394.so.22 (0x00007f3c50e5b000)
libv4l1.so.0 => /usr/lib/x86_64-linux-gnu/libv4l1.so.0 (0x00007f3c50c55000)
libavcodec-ffmpeg.so.56 => /usr/lib/x86_64-linux-gnu/libavcodec-ffmpeg.so.56 (0x00007f3c4f828000)
libavformat-ffmpeg.so.56 => /usr/lib/x86_64-linux-gnu/libavformat-ffmpeg.so.56 (0x00007f3c4f42a000)
libavutil-ffmpeg.so.54 => /usr/lib/x86_64-linux-gnu/libavutil-ffmpeg.so.54 (0x00007f3c4f1bb000)
libswscale-ffmpeg.so.3 => /usr/lib/x86_64-linux-gnu/libswscale-ffmpeg.so.3 (0x00007f3c4ef2b000) /lib64/ld-linux-x86-64.so.2 (0x000055b4ab2ea000)
libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007f3c4ed02000)
libxcb-dri3.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-dri3.so.0 (0x00007f3c4eafe000)
libxcb-present.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-present.so.0 (0x00007f3c4e8fb000)
libxcb-sync.so.1 => /usr/lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007f3c4e6f4000)
libxshmfence.so.1 => /usr/lib/x86_64-linux-gnu/libxshmfence.so.1 (0x00007f3c4e4f0000)
libglapi.so.0 => /usr/lib/x86_64-linux-gnu/libglapi.so.0 (0x00007f3c4e2c1000)
libXext.so.6 => /usr/lib/x86_64-linux-gnu/libXext.so.6 (0x00007f3c4e0af000)
libXdamage.so.1 => /usr/lib/x86_64-linux-gnu/libXdamage.so.1 (0x00007f3c4deab000)
libXfixes.so.3 => /usr/lib/x86_64-linux-gnu/libXfixes.so.3 (0x00007f3c4dca5000)
libX11-xcb.so.1 => /usr/lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007f3c4daa3000)
libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007f3c4d768000)
libxcb-glx.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-glx.so.0 (0x00007f3c4d54f000)
libxcb-dri2.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-dri2.so.0 (0x00007f3c4d34a000)
libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f3c4d127000)
libXxf86vm.so.1 => /usr/lib/x86_64-linux-gnu/libXxf86vm.so.1 (0x00007f3c4cf21000)
libdrm.so.2 => /usr/lib/x86_64-linux-gnu/libdrm.so.2 (0x00007f3c4cd12000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f3c4cb0d000)
liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007f3c4c8eb000)
libjbig.so.0 => /usr/lib/x86_64-linux-gnu/libjbig.so.0 (0x00007f3c4c6dc000)
libIex-2_2.so.12 => /usr/lib/x86_64-linux-gnu/libIex-2_2.so.12 (0x00007f3c4c4be000)
libIlmThread-2_2.so.12 => /usr/lib/x86_64-linux-gnu/libIlmThread-2_2.so.12 (0x00007f3c4c2b7000)
libgmodule-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgmodule-2.0.so.0 (0x00007f3c4c0b2000)
libpangocairo-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libpangocairo-1.0.so.0 (0x00007f3c4bea5000)
libatk-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libatk-1.0.so.0 (0x00007f3c4bc80000)
libcairo.so.2 => /usr/lib/x86_64-linux-gnu/libcairo.so.2 (0x00007f3c4b96b000)
libgdk_pixbuf-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0 (0x00007f3c4b749000)
libgio-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0 (0x00007f3c4b3c1000)
libpangoft2-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libpangoft2-1.0.so.0 (0x00007f3c4b1aa000)
libpango-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libpango-1.0.so.0 (0x00007f3c4af5e000)
libfontconfig.so.1 => /usr/lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007f3c4ad1b000)
libXrender.so.1 => /usr/lib/x86_64-linux-gnu/libXrender.so.1 (0x00007f3c4ab10000)
libXinerama.so.1 => /usr/lib/x86_64-linux-gnu/libXinerama.so.1 (0x00007f3c4a90d000)
libXi.so.6 => /usr/lib/x86_64-linux-gnu/libXi.so.6 (0x00007f3c4a6fc000)
libXrandr.so.2 => /usr/lib/x86_64-linux-gnu/libXrandr.so.2 (0x00007f3c4a4f1000)
libXcursor.so.1 => /usr/lib/x86_64-linux-gnu/libXcursor.so.1 (0x00007f3c4a2e7000)
libXcomposite.so.1 => /usr/lib/x86_64-linux-gnu/libXcomposite.so.1 (0x00007f3c4a0e4000)
libffi.so.6 => /usr/lib/x86_64-linux-gnu/libffi.so.6 (0x00007f3c49edb000)
libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007f3c49c6b000)
libGLU.so.1 => /usr/lib/x86_64-linux-gnu/libGLU.so.1 (0x00007f3c499fb000)
libXmu.so.6 => /usr/lib/x86_64-linux-gnu/libXmu.so.6 (0x00007f3c497e2000)
libpangox-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libpangox-1.0.so.0 (0x00007f3c495c2000)
libraw1394.so.11 => /usr/lib/x86_64-linux-gnu/libraw1394.so.11 (0x00007f3c493b2000)
libusb-1.0.so.0 => /lib/x86_64-linux-gnu/libusb-1.0.so.0 (0x00007f3c4919a000)
libv4l2.so.0 => /usr/lib/x86_64-linux-gnu/libv4l2.so.0 (0x00007f3c48f8c000)
libswresample-ffmpeg.so.1 => /usr/lib/x86_64-linux-gnu/libswresample-ffmpeg.so.1 (0x00007f3c48d6e000)
libva.so.1 => /usr/lib/x86_64-linux-gnu/libva.so.1 (0x00007f3c48b52000)
libzvbi.so.0 => /usr/lib/x86_64-linux-gnu/libzvbi.so.0 (0x00007f3c488c7000)
libxvidcore.so.4 => /usr/lib/x86_64-linux-gnu/libxvidcore.so.4 (0x00007f3c485b2000)
libx265.so.79 => /usr/lib/x86_64-linux-gnu/libx265.so.79 (0x00007f3c47993000)
libx264.so.148 => /usr/lib/x86_64-linux-gnu/libx264.so.148 (0x00007f3c475ef000)
libwebp.so.5 => /usr/lib/x86_64-linux-gnu/libwebp.so.5 (0x00007f3c47392000)
libwavpack.so.1 => /usr/lib/x86_64-linux-gnu/libwavpack.so.1 (0x00007f3c47169000)
libvpx.so.3 => /usr/lib/x86_64-linux-gnu/libvpx.so.3 (0x00007f3c46d45000)
libvorbisenc.so.2 => /usr/lib/x86_64-linux-gnu/libvorbisenc.so.2 (0x00007f3c46a9b000)
libvorbis.so.0 => /usr/lib/x86_64-linux-gnu/libvorbis.so.0 (0x00007f3c4686f000)
libtwolame.so.0 => /usr/lib/x86_64-linux-gnu/libtwolame.so.0 (0x00007f3c4664c000)
libtheoraenc.so.1 => /usr/lib/x86_64-linux-gnu/libtheoraenc.so.1 (0x00007f3c4640c000)
libtheoradec.so.1 => /usr/lib/x86_64-linux-gnu/libtheoradec.so.1 (0x00007f3c461f2000)
libspeex.so.1 => /usr/lib/x86_64-linux-gnu/libspeex.so.1 (0x00007f3c45fd9000)
libsnappy.so.1 => /usr/lib/x86_64-linux-gnu/libsnappy.so.1 (0x00007f3c45dd0000)
libshine.so.3 => /usr/lib/x86_64-linux-gnu/libshine.so.3 (0x00007f3c45bc3000)
libschroedinger-1.0.so.0 => /usr/lib/x86_64-linux-gnu/libschroedinger-1.0.so.0 (0x00007f3c458ee000)
libopus.so.0 => /usr/lib/x86_64-linux-gnu/libopus.so.0 (0x00007f3c456a3000)
libopenjpeg.so.5 => /usr/lib/x86_64-linux-gnu/libopenjpeg.so.5 (0x00007f3c45480000)
libmp3lame.so.0 => /usr/lib/x86_64-linux-gnu/libmp3lame.so.0 (0x00007f3c4520b000)
libgsm.so.1 => /usr/lib/x86_64-linux-gnu/libgsm.so.1 (0x00007f3c44ffc000)
libcrystalhd.so.3 => /usr/lib/x86_64-linux-gnu/libcrystalhd.so.3 (0x00007f3c44de1000)
libssh-gcrypt.so.4 => /usr/lib/x86_64-linux-gnu/libssh-gcrypt.so.4 (0x00007f3c44b97000)
librtmp.so.1 => /usr/lib/x86_64-linux-gnu/librtmp.so.1 (0x00007f3c4497b000)
libmodplug.so.1 => /usr/lib/x86_64-linux-gnu/libmodplug.so.1 (0x00007f3c445f0000)
libgme.so.0 => /usr/lib/x86_64-linux-gnu/libgme.so.0 (0x00007f3c443a1000)
libbluray.so.1 => /usr/lib/x86_64-linux-gnu/libbluray.so.1 (0x00007f3c44158000)
libgnutls.so.30 => /usr/lib/x86_64-linux-gnu/libgnutls.so.30 (0x00007f3c43e28000)
libbz2.so.1.0 => /lib/x86_64-linux-gnu/libbz2.so.1.0 (0x00007f3c43c17000)
libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007f3c43a13000)
libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007f3c4380c000)
libfreetype.so.6 => /usr/lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007f3c43562000)
libpixman-1.so.0 => /usr/lib/x86_64-linux-gnu/libpixman-1.so.0 (0x00007f3c432b9000)
libxcb-shm.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007f3c430b5000)
libxcb-render.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007f3c42eab000)
libselinux.so.1 => /lib/x86_64-linux-gnu/libselinux.so.1 (0x00007f3c42c88000)
libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007f3c42a6d000)
libharfbuzz.so.0 => /usr/lib/x86_64-linux-gnu/libharfbuzz.so.0 (0x00007f3c4280f000)
libthai.so.0 => /usr/lib/x86_64-linux-gnu/libthai.so.0 (0x00007f3c42605000)
libXt.so.6 => /usr/lib/x86_64-linux-gnu/libXt.so.6 (0x00007f3c4239c000)
libudev.so.1 => /lib/x86_64-linux-gnu/libudev.so.1 (0x00007f3c4237b000)
libv4lconvert.so.0 => /usr/lib/x86_64-linux-gnu/libv4lconvert.so.0 (0x00007f3c42101000)
libsoxr.so.0 => /usr/lib/x86_64-linux-gnu/libsoxr.so.0 (0x00007f3c41e9c000)
libnuma.so.1 => /usr/lib/x86_64-linux-gnu/libnuma.so.1 (0x00007f3c41c90000)
libogg.so.0 => /usr/lib/x86_64-linux-gnu/libogg.so.0 (0x00007f3c41a87000)
liborc-0.4.so.0 => /usr/lib/x86_64-linux-gnu/liborc-0.4.so.0 (0x00007f3c41806000)
libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007f3c41525000)
libgssapi_krb5.so.2 => /usr/lib/x86_64-linux-gnu/libgssapi_krb5.so.2 (0x00007f3c412da000)
libhogweed.so.4 => /usr/lib/x86_64-linux-gnu/libhogweed.so.4 (0x00007f3c410a7000)
libnettle.so.6 => /usr/lib/x86_64-linux-gnu/libnettle.so.6 (0x00007f3c40e71000)
libgmp.so.10 => /usr/lib/x86_64-linux-gnu/libgmp.so.10 (0x00007f3c40bf0000)
libxml2.so.2 => /usr/lib/x86_64-linux-gnu/libxml2.so.2 (0x00007f3c40835000)
libp11-kit.so.0 => /usr/lib/x86_64-linux-gnu/libp11-kit.so.0 (0x00007f3c405d0000)
libidn.so.11 => /usr/lib/x86_64-linux-gnu/libidn.so.11 (0x00007f3c4039d000)
libtasn1.so.6 => /usr/lib/x86_64-linux-gnu/libtasn1.so.6 (0x00007f3c4018a000)
libgraphite2.so.3 => /usr/lib/x86_64-linux-gnu/libgraphite2.so.3 (0x00007f3c3ff64000)
libdatrie.so.1 => /usr/lib/x86_64-linux-gnu/libdatrie.so.1 (0x00007f3c3fd5c000)
libSM.so.6 => /usr/lib/x86_64-linux-gnu/libSM.so.6 (0x00007f3c3fb53000)
libICE.so.6 => /usr/lib/x86_64-linux-gnu/libICE.so.6 (0x00007f3c3f939000)
libgomp.so.1 => /usr/lib/x86_64-linux-gnu/libgomp.so.1 (0x00007f3c3f717000)
libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007f3c3f502000)
libkrb5.so.3 => /usr/lib/x86_64-linux-gnu/libkrb5.so.3 (0x00007f3c3f230000)
libk5crypto.so.3 => /usr/lib/x86_64-linux-gnu/libk5crypto.so.3 (0x00007f3c3f000000)
libcom_err.so.2 => /lib/x86_64-linux-gnu/libcom_err.so.2 (0x00007f3c3edfc000)
libkrb5support.so.0 => /usr/lib/x86_64-linux-gnu/libkrb5support.so.0 (0x00007f3c3ebf1000)
libicuuc.so.55 => /usr/lib/x86_64-linux-gnu/libicuuc.so.55 (0x00007f3c3e85c000)
libuuid.so.1 => /lib/x86_64-linux-gnu/libuuid.so.1 (0x00007f3c3e657000)
libkeyutils.so.1 => /lib/x86_64-linux-gnu/libkeyutils.so.1 (0x00007f3c3e453000)
libicudata.so.55 => /usr/lib/x86_64-linux-gnu/libicudata.so.55 (0x00007f3c3c99b000)
undefined symbol:
_ZN2cv7imwriteERKSsRKNS_11_InputArrayERKSt6vectorIiSaIiEE (./ExctractCC) undefined symbol: _ZN2cv6imreadERKSsi (./ExctractCC)
除了最后两个未定义的符号。 它似乎与opencv链接，因为我可以阅读Imread，但重新安装opencv 2.4不起作用。
在我将Ubuntu从14.04升级到16.04之前，我和另一个曾经完美工作的项目有同样的错误，我做的另一个改变是下载g ++ 4.9。 我不确定是否应该安装缺少的库，编译器问题或其他问题。 如果有人有提示？
编辑：这是我的代码：
#include <iostream>
#include <sys/types.h>
#include <sys/stat.h>
#include <vector>
#include <fstream>
#include <iostream>
#include <algorithm>
#include <math.h>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv/cv.h>
#include <main.h>
#include <processImage.h>
#include <boost/lexical_cast.hpp>
#include <boost/algorithm/string.hpp>
using namespace std;
int main()
{
int maxHeight = 2500;
int normHeight = 2000;
int rectangleWidth = round((float)normHeight/200.0);
std::string list_images_train="data/list_images_train";
if(rectangleWidth <3)
{
rectangleWidth = 3;
}
//int numLines = countNumberOfLinesInFIle(list_images_train);
std::vector<std::string> filenames;
std::ifstream fid1(list_images_train.c_str(), std::ios::in);
std::string name;
int x=1;
while(std::getline(fid1,name))
{
filenames.push_back(name);
x+=1;
}
fid1.close();
int n=filenames.size();
for(int x=0;x<n;x++)
{
std::string folder="/home/kamel/TRAVAIL/Romain/build-ExctractCC-Desktop-Debug/"+filenames[x];
int statut=mkdir(folder.c_str(),S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
std::string imageName="data/"+ filenames[x]+".png";
std::string gtFile="data/"+ filenames[x] + ".gt";
//The error occurs here:
cv::Mat imgTest=(cv::imread(imageName.c_str(), CV_LOAD_IMAGE_GRAYSCALE));
double min,max;
imgTest.convertTo(imgTest,CV_64F);
cv::minMaxLoc(imgTest,&min,&max);
imgTest=(255*((imgTest - min)/(max-min)));
imgTest.convertTo(imgTest,CV_8U);
int height=imgTest.rows;
int width=imgTest.cols;
int evaluate=1;
if (gtFile.empty())
{
evaluate=0;
}
double ratio1= (float)maxHeight/ (float)height;
cv::resize(imgTest,imgTest,cv::Size(),ratio1,ratio1,cv::INTER_LANCZOS4);
height=imgTest.rows;
width=imgTest.cols;
cv::Mat binImg;
(cv::GaussianBlur(imgTest,imgTest,cv::Size(7,7),0,0));
imgTest.convertTo(imgTest,CV_8U);
double thrsh= cv::threshold(imgTest,binImg,0,255,CV_THRESH_BINARY_INV |CV_THRESH_OTSU);
std::vector<std::string> vars;
boost::split(vars,imageName, boost::is_any_of("/"),boost::token_compress_on);
cv::Mat binImg0= binImg.clone();
double ratio2= float(normHeight)/float(height);
if(imgTest.cols==0){
std::cout<<"Error reading file"<<std::endl;
}
cv::resize(imgTest,imgTest,cv::Size(),ratio2,ratio2,cv::INTER_LANCZOS4);
height=binImg.rows;
width=binImg.cols;
binImg/=255;
cv::resize(binImg,binImg,cv::Size(),ratio2,ratio2,cv::INTER_LANCZOS4);
cv::Mat imgcontour=binImg.clone();
std::vector<cv::Vec4i> hierarchy;
std::vector<std::vector<cv::Point> > CC;
cv::findContours(imgcontour, CC,hierarchy, CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE, cv::Point(0,0));
int sizeCC=CC.size();
for(int i=0;i<sizeCC;i++)
{
cv::Mat pointsf;
cv::Mat(CC[i]).convertTo(pointsf, CV_32F);
cv::Rect box=cv::boundingRect(pointsf);
cv::Mat tmpimg=binImg.colRange(box.x,box.x+box.width).rowRange(box.y,box.y + box.height);
std::ostringstream name;
name << folder << "/CC"<<i << ".png";
cv::imwrite(name.str(),tmpimg);
}
}
return 0;
}