Add OpenCV and FFMPEG to CMake

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.15)
 project (
     RoboMasterSDK
     VERSION 2.0.0
-    LANGUAGES C
+    LANGUAGES C CXX
 )
 
 set_property(GLOBAL PROPERTY C_STANDARD 17)
@@ -30,19 +30,27 @@ target_include_directories(robomaster
     include
 )
 
-include(FetchContent)
-FetchContent_Declare (
-    SDL2
-    GIT_REPOSITORY https://github.com/libsdl-org/SDL
-    GIT_TAG release-2.0.20
-    GIT_SHALLOW TRUE
-)
-FetchContent_MakeAvailable(SDL2)
+find_package(SDL2 REQUIRED)
+find_package(OpenCV REQUIRED)
+find_package(PkgConfig REQUIRED)
+
+pkg_check_modules(FFMPEG REQUIRED IMPORTED_TARGET libavcodec libavformat libavutil libswscale)
 
 add_executable(robomasterapp
-    src/sdl.c
+    src/sdl.cpp
 )
 target_link_libraries(robomasterapp
     robomaster
-    SDL2-static
+    SDL2::SDL2
+    ${OpenCV_LIBS}
+    PkgConfig::FFMPEG
+)
+
+add_executable(stream
+    src/stream.cpp
+)
+target_link_libraries(stream
+    SDL2::SDL2
+    ${OpenCV_LIBS}
+    PkgConfig::FFMPEG
 )