Add opencv optional dependency to superbuild project

Documentation/VeloView_Developer_Guide.md

@@ -157,6 +157,11 @@ The following packages are needed to build on Ubuntu 16.04:
 - freeglut3-dev
 - pkg-config
 
+### If opencv if enabled:
+- libavformat-dev
+- libavdevice-dev
+- libavcodec-dev
+
 
 ### Linux build instructions <a name="linux-build-instructions"></a>
 1. clone VeloView's source code repository to a directory of your chosing, for example:

Superbuild/CMakeLists.txt

@@ -72,6 +72,7 @@ function (superbuild_find_projects var)
     eigen
     liblas
     freetype
+    opencv
     paraview
     pcap
     png

Superbuild/Projects/opencv.cmake

+superbuild_add_project(opencv
+  
+  CMAKE_ARGS
+  -DCMAKE_CXX_STANDARD=11
+  -DCMAKE_CXX_STANDARD_REQUIRED=true
+  -DEIGEN_INCLUDE_PATH=<INSTALL_DIR>/include/eigen3
+  -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>/opencv
+  -DWITH_FFMPEG=ON
+  -DWITH_TBB=ON
+  -DWITH_GTK=ON
+  -DWITH_V4L=ON
+  -DWITH_OPENGL=ON
+  -DWITH_CUBLAS=ON
+  -DCUDA_NVCC_FLAGS=-D_FORCE_INLINES
+  -DWITH_LIBV4L=ON
+  -DBUILD_TESTING=false
+  -DBUILD_EXAMPLES=false
+  -DGFLAGS=false
+  )

Superbuild/versions.cmake

@@ -65,3 +65,7 @@ superbuild_set_revision(qhull
 superbuild_set_revision(flann
   GIT_REPOSITORY git://github.com/mariusmuja/flann.git
   GIT_TAG 1.9.1)
+
+superbuild_set_revision(opencv
+  GIT_REPOSITORY https://github.com/opencv/opencv.git
+  GIT_TAG 4.0.0)

VelodyneHDL/CMakeLists.txt

@@ -108,6 +108,15 @@ if (ENABLE_Ceres)
   include_directories(${SYSTEM_OPTION} ${CERES_INCLUDE_DIRS})
 endif(ENABLE_Ceres)
 
+#--------------------------------------
+# Opencv dependency
+#--------------------------------------
+option(ENABLE_OpenCV OFF "OpenCV is required for handling lidar-camera multisensor systems")
+if (ENABLE_OpenCV)
+  find_package(OpenCV REQUIRED)
+  include_directories(${SYSTEM_OPTION} ${OpenCV_INCLUDE_DIRS})
+endif(ENABLE_OpenCV)
+
 #-----------------------------------------------------------------------------
 # Build Paraview Plugin
 #-----------------------------------------------------------------------------