Fixing ffmpeg dll copying on Windows

3rdparty/ffmpeg/CMakeLists.txt

@@ -9,8 +9,18 @@ set(module_name "${CMAKE_CURRENT_SOURCE_DIR}/${module_bare_name}")
 
 message(STATUS "ffmpeg output dir: ${EXECUTABLE_OUTPUT_PATH}")
 
-add_custom_target(opencv_ffmpeg ALL
-                  COMMAND ${CMAKE_COMMAND} -E copy "${module_name}" "${EXECUTABLE_OUTPUT_PATH}/${module_bare_name}"
-                  COMMENT "Copying ${module_name} to the output directory")
+if(CMAKE_VERSION VERSION_GREATER "2.8.2")
+  add_custom_target(opencv_ffmpeg ALL
+                    COMMAND ${CMAKE_COMMAND} -E copy "${module_name}" "${EXECUTABLE_OUTPUT_PATH}/$<CONFIGURATION>/${module_bare_name}"
+                    COMMENT "Copying ${module_name} to the output directory")
+elseif(MSVC)
+  add_custom_target(opencv_ffmpeg ALL
+                    COMMAND ${CMAKE_COMMAND} -E copy "${module_name}" "${EXECUTABLE_OUTPUT_PATH}/${CMAKE_BUILD_TYPE}/${module_bare_name}"
+                    COMMENT "Copying ${module_name} to the output directory")
+else()
+  add_custom_target(opencv_ffmpeg ALL
+                    COMMAND ${CMAKE_COMMAND} -E copy "${module_name}" "${EXECUTABLE_OUTPUT_PATH}/${module_bare_name}"
+                    COMMENT "Copying ${module_name} to the output directory")
+endif()
 
 install(FILES ${module_name} DESTINATION bin COMPONENT main)