[python] cmake error 'the source does not appear to contain CMakeLists.txt'

I'm installing opencv in ubuntu 16.04. After installing the necessary prerequisites I used the following command:-

kvs@Hunter:~/opencv_contrib$ mkdir build
kvs@Hunter:~/opencv_contrib$ cd build

but it produced an error:-

CMake Error: The source directory "/home/kvs/opencv_contrib" does not appear to contain CMakeLists.txt.
Specify --help for usage, or press the help button on the CMake GUI.

I used the command provided in the folder 'module' documentation. How do I solve it? I tried the answers here at stack-overflow and a few other question but still can't figure it out.

Project Git repository here.

This question is related to python opencv

The answer is

This reply may be late but it may help users having similar problem. The opencv-contrib (available at https://github.com/opencv/opencv_contrib/releases) contains extra modules but the build procedure has to be done from core opencv (available at from https://github.com/opencv/opencv/releases) modules.

Follow below steps (assuming you are building it using CMake GUI)

  1. Download openCV (from https://github.com/opencv/opencv/releases) and unzip it somewhere on your computer. Create build folder inside it

  2. Download exra modules from OpenCV. (from https://github.com/opencv/opencv_contrib/releases). Ensure you download the same version.

  3. Unzip the folder.

  4. Open CMake

  5. Click Browse Source and navigate to your openCV folder.

  6. Click Browse Build and navigate to your build Folder.

  7. Click the configure button. You will be asked how you would like to generate the files. Choose Unix-Makefile from the drop down menu and Click OK. CMake will perform some tests and return a set of red boxes appear in the CMake Window.

  8. Search for "OPENCV_EXTRA_MODULES_PATH" and provide the path to modules folder (e.g. /Users/purushottam_d/Programs/OpenCV3_4_5_contrib/modules)

  9. Click Configure again, then Click Generate.

  10. Go to build folder

# cd build
# make
# sudo make install
  1. This will install the opencv libraries on your computer.

Since you add .. after cmake, it will jump up and up (just like cd ..) in the directory. But if you want to run cmake under the same folder with CMakeLists.txt, please use . instead of ...