Could not find module FindOpenCV.cmake ( Error in

Question

I wrote a CMakeLists.txt for a project in C++, which uses OpenCV libraries. When I try to create the project using cmake, I get the next configuration problem:

CMake Error at CMakeLists.txt:15 (find_package):
  Could not find module FindOpenCV.cmake or a configuration file for package
  OpenCV.

  Adjust CMAKE_MODULE_PATH to find FindOpenCV.cmake or set OpenCV_DIR to the
  directory containing a CMake configuration file for OpenCV.  The file will
  have one of the following names:

    OpenCVConfig.cmake
    opencv-config.cmake

The fact is that I have an environment variable for the path which I use in Visual Studio with no problems. If I don't include OpenCV, then I can configure and generate with no problem, but I need to solve the problem. I don't understand why cmake cannot find the OpenCV path or how to fix it.

I also used the recommendations mentioned in this link: FindOpenCV.cmake

Does anybody had this problem too?

Answer 1

Followed @hugh-pearse 's and @leszek-hanusz 's answers, with a little tweak. I had installed opencv from ubuntu 12.10 repository (libopencv-)* and had the same problem. Couldn't solve it with export OpenCV_DIR=/usr/share/OpenCV/ (since my OpenCVConfig.cmake whas there). It was solved when I also changed some lines on the OpenCVConfig.cmake file:

# ======================================================
# Include directories to add to the user project:
# ======================================================

# Provide the include directories to the caller

#SET(OpenCV_INCLUDE_DIRS "${OpenCV_INSTALL_PATH}/include/opencv;${OpenCV_INSTALL_PATH}/include")

SET(OpenCV_INCLUDE_DIRS "/usr/include/opencv;/usr/include/opencv2")
INCLUDE_DIRECTORIES(${OpenCV_INCLUDE_DIRS})

# ======================================================
# Link directories to add to the user project:
# ======================================================

# Provide the libs directory anyway, it may be needed in some cases.

#SET(OpenCV_LIB_DIR "${OpenCV_INSTALL_PATH}/lib")

SET(OpenCV_LIB_DIR "/usr/lib")

LINK_DIRECTORIES(${OpenCV_LIB_DIR})

And that worked on my Ubuntu 12.10. Remember to add the target_link_libraries(yourprojectname ${OpenCV_LIBS}) in your CMakeLists.txt.

Answer 2

On my Fedora machine, when I typed "make" I got an error saying it could not find "cv.h". I fixed this by modifying my "OpenCVConfig.cmake" file.

Before:

SET(OpenCV_INCLUDE_DIRS "${OpenCV_INSTALL_PATH}/include/opencv;${OpenCV_INSTALL_PATH}/include")

SET(OpenCV_LIB_DIR "${OpenCV_INSTALL_PATH}/lib64")

After:

SET(OpenCV_INCLUDE_DIRS "/usr/include/opencv;/usr/include/opencv2")

SET(OpenCV_LIB_DIR "/usr/lib64")

Answer 3

I am using Windows and get the same error message. I find another problem which is relevant. I defined OpenCV_DIR in my path at the end of the line. However when I typed "path" in the command line, my OpenCV_DIR was not shown. I found because Windows probably has a limit on how long the path can be, it cut my OpenCV_DIR to be only part of what I defined. So I removed some other part of the path, now it works.

Answer 4

I had this exact same problem. I fixed it by adding the following line to my FindOpenCV.cmake file. Put it anywhere at the top before the rest of the code.

set (OpenCV_DIR /home/cmake/opencv/compiled) #change the path to match your complied directory of opencv

Basically you are telling FindOpenCV.cmake where to find opencv files assuming the other compilation can find the FindOpenCV.cmake

Answer 5

if you are on windows, you can add opencv path to OpenCV_DIR yourself. (OpenCV_DIR is in the red region)

the path is like "D:/opencv244/build".

you can find file "OpenCVConfig.cmake" under the path.

Answer 6

If you are on Linux, you just need to fill the OpenCV_DIR variable with the path of opencv (containing the OpenCVConfig.cmake file)

export OpenCV_DIR=<path_of_opencv>