#include <opencv2/opencv.hpp> //头文件
using namespace cv; //包含cv命名空间
int main()
{
Mat img=imread("cornea.jpg");
imshow("src",img);
waitKey(0);
return 0;
}
And I compile it with:
g++ test.cpp -o test pkg-config opencv --cflags --libs opencv
Which gives me:
/usr/bin/ld: warning: libicui18n.so.54, needed by //home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5, not found (try using -rpath or -rpath-link)<br/>
/usr/bin/ld: warning: libicuuc.so.54, needed by //home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5, not found (try using -rpath or -rpath-link)<br/>
/usr/bin/ld: warning: libicudata.so.54, needed by //home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5, not found (try using -rpath or -rpath-link)<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_clone_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘uenum_next_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘u_strToLower_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getStandardName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_setAttribute_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_setMillis_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_strcoll_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_setSubstChars_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_getTimeZoneDisplayName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_openCountryTimeZones_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_fromUnicode_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_open_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getDefaultName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_open_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_inDaylightTime_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucol_getSortKey_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getAvailableName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_get_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_openTimeZoneIDEnumeration_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_getDSTSavings_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_open_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_openTimeZones_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_toUnicode_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘u_strToUpper_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘u_errorName_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘uenum_close_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_countAvailable_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getMaxCharSize_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_getAlias_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucal_getDefaultTimeZone_54’未定义的引用<br/>
//home/lmk/Qt5.5.0/5.5/gcc/lib/libQt5Core.so.5：对‘ucnv_compareNames_54’未定义的引用<br/>
collect2: error: ld returned 1 exit status
The backticks in command line pkg-config opencv --cflags --libs opencv is invisible. I have not got the reason now.
Indeed,in early days, I have installed Qt. But now, I do not want my program have something to do with Qt. In order that my program is not affected by the Qt library function, I shielded the path variables of Qt in the /etc/bash.bashrc file and installed a new gcc of 5.3.0. But the same error is still existing!
I'm using Ubuntu 14.04
Download ICU-54.1 from here
http://www.linuxfromscratch.org/blfs/view/7.7/general/icu.html
and install manually.
For me this solved the problem.
Related
I am trying to install openCV on my Mac, and have gotten to the point of calling this command:
pkg-config --cflags --libs opencv
and get the error:
Variable 'prefix not defined in '/usr/local/lib/pkgconfig/opencv.pc'
I've tried looking online and cannot find anything about this error. Any advice?
Ld build/Release-iphoneos/Demo.app/Demo normal arm64
cd /Users/meitu/Desktop/Demo3
export IPHONEO _ DEPLOYMENT _ TARGET=11.0
you have to install the debug version of OpenCV 3.3.
If you use cmake follow the instruction given by
https://docs.opencv.org/2.4/doc/tutorials/introduction/linux_gcc_cmake/linux_gcc_cmake.html
For integration into a makefile under linux you can use the useful commands
pkg-config --cflags opencv
pkg-config --libs opencv
in your Makefile.
Maybe you must compile openCV by yourself setting the debug option.
I am trying to compile a short test program that requires Qt4, but have trouble properly linking to the Qt4 library. I have installed Qt4 via
sudo apt-get install qt4-dev-tools
The program code looks like this
#include <QtCore>
#include <iostream>
int main() {
std::cout << "Qt version: " << qVersion() << std::endl;
}
The shared library libQtCore.so is at /usr/lib/x86_64-linux-gnu but trying to compile the following way
g++ -L/usr/lib/x86_64-linux-gnu -Wall -o test.exe test.cpp -lQtCore
returns an error message that there is no file or directory called QtCore.
I have also tried to directly use the QtCore source code, but have received the following error message:
/tmp/ccljEHOY.o: In function main':
test.cpp:(.text+0xa): undefined reference toqVersion()'
collect2: error: ld returned 1 exit status
What am I doing wrong here?
Thanks
Ips
The compiler was not able to find QtCore file because you need to add path with Qt to the list of directories to be searched for header files.
You can use the pkg-config to get proper flags:
$:pkg-config QtCore --cflags
-DQT_SHARED -I/usr/include/qt4 -I/usr/include/qt4/QtCore
For linking:
$:pkg-config QtCore --libs
-lQtCore
You can use pkg-config when calling the compiler:
g++ test.cpp `pkg-config QtCore --cflags --libs`
or
g++ `pkg-config QtCore --cflags` test.cpp `pkg-config QtCore --libs`
Note that the following way won't work:
g++ `pkg-config QtCore --cflags --libs` test.cpp
I'm using Kubuntu and have some Problems with linking OpenCv ( 2.4.6.1 ) Librarys ( I guess ).
So I've been using this tutorial http://karytech.blogspot.de/2012/05/opencv-24-on-ubuntu-1204.html and got the installation tested ok ( section: ./opencv_test_core ). Then I downloaded the testfile below but could make it work. Tried some other code always the same error:
g++ -L/usr/local/lib -lcv -lcxcore -lcvaux -lhighui -lm hello.cpp
/usr/bin/ld: cannot find -lcv
/usr/bin/ld: cannot find -lcxcore
/usr/bin/ld: cannot find -lcvaux
/usr/bin/ld: cannot find -lhighui
collect2: Fehler: ld gab 1 als Ende-Status zurück ( ld exit status is 1 )
( as for the strange library names in the tutorial i also tried -lopencv_calib3d ... )
then tried it in code::blocks and get this:
main.c undefined reference to cvGetRows
Headers are in /usr/local/include/opencv
/usr/local/include/opencv2
Librarys are in usr/local/lib
( If that helps ):
$ pkg-config --cflags opencv
returns: -I/usr/local/include/opencv -I/usr/local/include
$ pkg-config --libs opencv
returns: /usr/local/lib/libopencv_calib3d.so /usr/local/lib/libopencv_contrib.so ...
$ apt-cache search opencv
returns: opencv-doc - OpenCV documentation and examples
python-opencv - Python-Anbindungen für die OpenCV-Bibliothek
libavcodec-extra-53 - Libav codec library ...
To link against OpenCV, you have to pass g++ (which will run ld internally) where the libraries are (if they are not standard ones). You can do it manually, if you want to link only some of them.
But the fastest way is to rely on pkg-config:
g++ faceDetect.cpp $(pkg-config --libs opencv --cflags)
However, in the package there's a Makefile, just cd the directory you've extracted that archive, and run make.
I want to use OpenCV as a static library. After compiling the library as a static library now i'm testing with some examples to see all the dependencies.
The dependencies added to compile are -staticpkg-config --libs opencv-lpthread -ljpeg -ltiff -lz -ljasper -lpng12
But obtain the following Error message:
g++ -c -g -Wall -O2 `pkg-config --cflags opencv` formas.cpp
g++ -g -Wall -O2 `pkg-config --cflags opencv` formas.o -o paint -static `pkg-config --libs opencv` -lpthread -ljpeg -ltiff -lz -ljasper -lpng12
/usr/local/lib/libopencv_core.a(system.o): In function `cv::tempfile(char const*)':
system.cpp:(.text._ZN2cv8tempfileEPKc+0x3a): warning: the use of `tmpnam' is dangerous, better use `mkstemp'
/usr/local/lib/libopencv_core.a(system.o): In function `cv::getTickCount()':
system.cpp:(.text._ZN2cv12getTickCountEv+0x2a): undefined reference to `clock_gettime'
/usr/local/lib/libopencv_highgui.a(grfmt_png.o): In function `cv::PngDecoder::readHeader()':
grfmt_png.cpp:(.text._ZN2cv10PngDecoder10readHeaderEv+0xde): undefined reference to `png_set_longjmp_fn'
/usr/local/lib/libopencv_highgui.a(grfmt_png.o): In function `cv::PngEncoder::write(cv::Mat const&, std::vector<int, std::allocator<int> > const&)':
grfmt_png.cpp:(.text._ZN2cv10PngEncoder5writeERKNS_3MatERKSt6vectorIiSaIiEE+0x134): undefined reference to `png_set_longjmp_fn'
/usr/local/lib/libopencv_highgui.a(grfmt_png.o): In function `cv::PngDecoder::readData(cv::Mat&)':
grfmt_png.cpp:(.text._ZN2cv10PngDecoder8readDataERNS_3MatE+0x141): undefined reference to `png_set_longjmp_fn'
collect2: ld returned 1 exit status
make: *** [all] Error 1
I made something wrong or there an error in OpenCV library.
OpenCV version: 2.3.1 (latest version)
formas --> example which create an image an draw some figures and save into a file. So simple.
Thanks in advance.
It seems you have compiled OpenCV with libpng 1.4 or newer but trying to link with libpng 1.2
What cmake command have you used to configure OpenCV?
Update:
You need to add -lrt to the list of libraries you link for the clock_gettime function.