Allow to control C++ standard to use

.github/workflows/cmake-ci.yml

@@ -20,13 +20,16 @@ jobs:
         os: [ubuntu-latest, macos-latest]
         build_type: [Release, Debug]
         skip_meson: [false]
+        cxx_latest: [On]
         include:
           - os: ubuntu-20.04
             build_type: Release
             skip_meson: true
+            cxx_latest: Off
           - os: ubuntu-20.04
             build_type: Debug
             skip_meson: true
+            cxx_latest: Off
 
 
     # The CMake configure and build commands are platform agnostic and should work equally
@@ -40,12 +43,13 @@ jobs:
       OS_NAME: ${{ matrix.os }}
       BUILD_TYPE: ${{ matrix.build_type }}
       SKIP_MESON: ${{ matrix.skip_meson }}
+      CXX_LATEST: ${{ matrix.cxx_latest }}
 
     steps:
     - uses: actions/checkout@v3
 
     - name: Dump environment variables
-      run: echo "OS_NAME=$OS_NAME, BUILD_TYPE=$BUILD_TYPE, SKIP_MESON=$SKIP_MESON"
+      run: echo "OS_NAME=$OS_NAME, BUILD_TYPE=$BUILD_TYPE, SKIP_MESON=$SKIP_MESON, CXX_LATEST=$CXX_LATEST"
 
     - name: Install packages for Linux
       if: ${{ matrix.os != 'macos-latest' && matrix.os != 'windows-latest' }}
@@ -58,7 +62,7 @@ jobs:
     - name: Configure CMake
       # Configure CMake in a 'build' subdirectory. `CMAKE_BUILD_TYPE` is only required if you are using a single-configuration generator such as make.
       # See https://cmake.org/cmake/help/latest/variable/CMAKE_BUILD_TYPE.html?highlight=cmake_build_type
-      run: cmake -B ${{github.workspace}}/build -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
+      run: cmake -B ${{github.workspace}}/build -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -DAV_CXX_LATEST=${{ matrix.cxx_latest }}
 
     - name: Build
       # Build your program with the given configuration

CMakeLists.txt

@@ -12,10 +12,16 @@ set(FFMPEG_PKG_CONFIG_SUFFIX "" CACHE STRING "This suffix uses for FFmpeg compon
 set(AV_ENABLE_STATIC On CACHE BOOL "Enable static library build (On)")
 set(AV_ENABLE_SHARED On CACHE BOOL "Enable shared library build (On)")
 set(AV_BUILD_EXAMPLES On CACHE BOOL "Build example applications (On)")
+set(AV_CXX_LATEST On CACHE BOOL "Use most modern C++ compiler features (On), otherwise use C++17")
 
-# Compiler-specific C++11 activation.
-set(CMAKE_CXX_STANDARD 20)
-set(CMAKE_CXX_STANDARD_REQUIRED no)
+# Compiler-specific Modern C++ activation.
+if (AV_CXX_LATEST)
+    set(CMAKE_CXX_STANDARD 23)
+    set(CMAKE_CXX_STANDARD_REQUIRED no)
+else()
+    set(CMAKE_CXX_STANDARD 17)
+    set(CMAKE_CXX_STANDARD_REQUIRED yes)
+endif()
 
 # Warnings
 set (AVCPP_WARNING_OPTIONS