OpenCV CUDA CMake error

Problem

I was building OpenCV using CMake and got this error:

CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake files:
opencv_dep_CUDA_nppi_LIBRARY

Solution

The error was related to CUDA and probably some dependency on the NVIDIA Performance Primitives (NPP) library. Since, I needed neither, I rebuilt OpenCV without CUDA support as described here by setting WITH_CUDA=OFF.