Home/ Questions/Q 7165457
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-28T14:15:11+00:00

I am trying to use the Qt new functions described here: http://opencv.willowgarage.com/documentation/cpp/qt_new_functions.html#cv-createbutton And I

  • 0

I am trying to use the Qt new functions described here:
http://opencv.willowgarage.com/documentation/cpp/qt_new_functions.html#cv-createbutton

And I also found this topic on SO:
openCV 2.2 createButton LNK 2019 error in Visual Studio 2010
but compiling with QT didn’t work.

Anyway, according to my searches it seems to be a linking problem. My doubt is that I already compiled OpenCV (without QT) but I can use the createTrackbar normally.

I tried using the createButton as this:

cv::createButton("buttonCanny",    buttonCallBackCanny,NULL,CV_RADIOBOX,true);

But I get this error:

undefined reference to `cv::createButton(std::string const&, void
()(int, void), void*, int, bool)’

I tried the cvCreateButton but I get the same error.

I have this setup
C/C++ Build -> Settings -> Tool Settings -> MingGW C++ Linker -> Libraries (all the .dll from compiled OpenCV)

  • libopencv_calib3d230
  • opencv_ffmpeg
  • libopencv_contrib230
  • libopencv_core230
  • libopencv_features2d230
  • libopencv_flann230
  • libopencv_gpu230
  • libopencv_highgui230
  • libopencv_imgproc230
  • libopencv_legacy230
  • libopencv_ml230
  • libopencv_objdetect230
  • libopencv_video230

C/C++ Build -> Settings -> Tool Settings -> MingGW C++ Linker -> Search Path (“C:\opencvbin\bin” where the Dll are)

C/C++ Build -> Settings -> Tool Settings -> GCC C++ Compiler -> Includes
“C:\OpenCV2.3\build\include”

Any suggestions?

Thank you!

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    Ok, I made some mistakes.

    Firstly, I wasn’t downloading the source code of QT, only the SDK, without source code.
    The necessary libs and executables where there.

    Secondly, I had to add some entries in the CMake Gui,

    I was ignoring this message:
    Could NOT find Qt4 (missing: QT_QMAKE_EXECUTABLE QT_MOC_EXECUTABLE QT_RCC_EXECUTABLE QT_UIC_EXECUTABLE QT_INCLUDE_DIR QT_LIBRARY_DIR QT_QTCORE_LIBRARY)

    then, I set

    • QT_QMAKE_EXECUTABLE = C:\Qt\4.8.0\bin\qmake.exe
    • QT_MOC_EXECUTABLE = C:\Qt\4.8.0\bin\moc.exe
    • QT_RCC_EXECUTABLE = C:\Qt\4.8.0\bin\rcc.exe
    • QT_UIC_EXECUTABLE = C:\Qt\4.8.0\bin\uic.exe
    • QT_INCLUDE_DIR = C:\Qt\4.8.0\include

    and it worked fine.

    Trackbar seems to work without Qt, so they probably use their own implementation of a trackbar when there is no Qt available.

    Thanks!

    • 0