MACRO(USE_VIDEOINPUT)
  FIND_PACKAGE(VideoInput)
  IF ((NOT VideoInput_FOUND) AND (${ARGC} LESS 1))
    USING_MESSAGE("Skipping because of missing VideoInput")
    RETURN()
  ENDIF((NOT VideoInput_FOUND) AND (${ARGC} LESS 1))
  IF(NOT VideoInput_USED AND VideoInput_FOUND)
    SET(VideoInput_USED TRUE)
    ADD_DEFINITIONS(-D HAVE_VIDEOINPUT)  
    
    INCLUDE_DIRECTORIES(SYSTEM ${VideoInput_INCLUDE_DIR})
    SET(EXTRA_LIBS ${EXTRA_LIBS} ${VideoInput_LIBRARIES})
    IF(UNIX AND NOT APPLE)
      SET(EXTRA_LIBS ${EXTRA_LIBS})
    ENDIF()
  ENDIF()
ENDMACRO(USE_VIDEOINPUT)