CV_GRAY2BGR in ch8/direct_method.cpp and ch8/optical_flow.cpp is the usage of OpenCV3, but ch8 project uses OpenCV4. It will raise errors and i have changed all of it to COLOR_GRAY2BGR, the alternatives of CV_GRAY2BGR in OpenCV4. I have compiled and tested the project.
CV_GRAY2BGRinch8/direct_method.cppandch8/optical_flow.cppis the usage of OpenCV3, butch8project uses OpenCV4. It will raise errors and i have changed all of it toCOLOR_GRAY2BGR, the alternatives ofCV_GRAY2BGRin OpenCV4. I have compiled and tested the project.