问题
I am trying to build OpenCV according to these instructions. After generating with CMake I opened OpenCV.sln in the build folder, switched to Release mode and built ALL_BUILD successfully. But when I try to build the INSTALL option under CMake, I get errors like this:
Error LNK2001 unresolved external symbol "public: virtual struct QMetaObject const * __cdecl cvv::qtutil::Signal::metaObject(void)const "
Error LNK2019 unresolved external symbol "public: void __cdecl cvv::qtutil::ZoomableImage::updateConversionResult(class cv::Mat const &,enum cvv::qtutil::ImageConversionResult)const "
...
I am installing OpenCV 4.2 on Windows 10 with Visual Studio 19. How can I solve this problem?
Here is an image of the error messages in Visual Studio:
回答1:
Turning my comments into an answer:
The GitHub issue described here references similar errors to those you have posted. While the suggested "solution" seems more like a work-around, it may help resolve the issue. First, try building without the cvv module (an interactive GUI component of OpenCV), by running CMake with the BUILD_opencv_cvv variable set to OFF:
cmake -DBUILD_opencv_cvv=OFF ...
You can also set the variable using the CMake GUI, by clicking the Add Entry button, and defining BUILD_opencv_cvv to OFF.
The GitHub issue further explains that if there are still undefined reference errors after making this change, you can also try setting BUILD_opencv_world to OFF as well.
cmake -DBUILD_opencv_cvv=OFF -DBUILD_opencv_world=OFF ...
This may help get things building successfully, but it should be noted that these disabled modules will be left out of your build.
来源：https://stackoverflow.com/questions/59753002/linking-errors-for-qt-and-cvv-when-building-opencv-in-windows-10