CMake Error at E:/AutonomousNavigationRobot/Opencv3.0/opencv_contrib-master/opencv_contrib-master/modules/dnn/cmake/download_protobuf.cmake:23 (ocv_download):
Unknown CMake command "ocv_download".
Call Stack (most recent call first):
E:/AutonomousNavigationRobot/Opencv3.0/opencv_contrib-master/opencv_contrib-master/modules/dnn/cmake/download_protobuf.cmake:51 (ocv_protobuf_download)
E:/AutonomousNavigationRobot/Opencv3.0/opencv_contrib-master/opencv_contrib-master/modules/dnn/cmake/OpenCVFindLibProtobuf.cmake:30 (include)
E:/AutonomousNavigationRobot/Opencv3.0/opencv_contrib-master/opencv_contrib-master/modules/dnn/CMakeLists.txt:38 (include)