问题：
CMake Error at CMakeLists.txt:3 (find_package):
By not providing "FindOpenCV.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "OpenCV", but
CMake did not find one.
Could not find a package configuration file provided by "OpenCV" with any
of the following names:
OpenCVConfig.cmake
opencv-config.cmake
Add the installation prefix of "OpenCV" to CMAKE_PREFIX_PATH or set
"OpenCV_DIR" to a directory containing one of the above files. If "OpenCV"
provides a separate development package or SDK, be sure it has been
installed.
解决方法：
打开你的CMakeLists.txt，添加set(OpenCV_DIR D:/Opencv2.4/opencv/build) 注意这是你的OpenCVConfig.cmake的路径（注意路径中的斜杠方向）
再编译就可以啦