Use system FFmpeg for VP9 playback on Linux

.github/workflows/build.yml

@@ -289,9 +289,15 @@ jobs:
             clang \
             glslang-tools \
             libasound2-dev \
+            libavcodec-dev \
+            libavfilter-dev \
+            libavformat-dev \
+            libavutil-dev \
             libdbus-1-dev \
             libgl1-mesa-dev \
             libpulse-dev \
+            libswresample-dev \
+            libswscale-dev \
             libudev-dev \
             libwayland-dev \
             libx11-dev \
@@ -304,6 +310,7 @@ jobs:
             libxss-dev \
             lld \
             ninja-build \
+            pkg-config \
             wayland-protocols
 
       - name: Install Qt 6.10.3

3rdparty/CMakeLists.txt

@@ -88,6 +88,13 @@ set(SPDLOG_FMT_EXTERNAL ON CACHE BOOL "" FORCE)
 set(SPDLOG_NO_EXCEPTIONS ON CACHE BOOL "" FORCE)
 add_subdirectory(spdlog EXCLUDE_FROM_ALL)
 
+if (NOT TARGET FFmpeg::ffmpeg AND CMAKE_SYSTEM_NAME STREQUAL "Linux")
+	find_package(PkgConfig REQUIRED)
+	pkg_check_modules(FFMPEG REQUIRED IMPORTED_TARGET GLOBAL
+		libavformat libavcodec libswscale libavutil libavfilter libswresample)
+	add_library(FFmpeg::ffmpeg ALIAS PkgConfig::FFMPEG)
+endif()
+
 if (NOT TARGET FFmpeg::ffmpeg)
 	# On macOS the target arch is driven by CMAKE_OSX_ARCHITECTURES, not the host
 	# CMAKE_SYSTEM_PROCESSOR (which reports arm64 even for an x86_64/Rosetta build).

CMakeLists.txt

@@ -317,24 +317,10 @@ endif()
 
 set(kyty_emulator_link_libraries common Vulkan::Headers spirv-tools-opt spirv-tools SDL2-static imgui xxhash FFmpeg::ffmpeg fmt::fmt nlohmann_json::nlohmann_json LibAtrac9 kyty_git_version Zydis::Zydis xbyak::xbyak)
 
-# Linux system libraries required by the static FFmpeg archive.
+# Linux system libraries.
 if(LINUX)
 	find_package(Threads REQUIRED)
 	list(APPEND kyty_emulator_link_libraries m ${CMAKE_DL_LIBS} Threads::Threads)
-
-	# Optional FFmpeg dependencies.
-	find_package(ZLIB)
-	if(ZLIB_FOUND)
-		list(APPEND kyty_emulator_link_libraries ZLIB::ZLIB)
-	endif()
-	find_library(KYTY_BZ2_LIBRARY bz2)
-	if(KYTY_BZ2_LIBRARY)
-		list(APPEND kyty_emulator_link_libraries ${KYTY_BZ2_LIBRARY})
-	endif()
-	find_library(KYTY_LZMA_LIBRARY lzma)
-	if(KYTY_LZMA_LIBRARY)
-		list(APPEND kyty_emulator_link_libraries ${KYTY_LZMA_LIBRARY})
-	endif()
 endif()
 
 set(inc_headers

README.md

@@ -165,13 +165,14 @@ The finished application and its runtime dependencies will be placed in
 
 ### Building on Linux
 
-Install the toolchain and the libraries the bundled SDL2 needs. Without the audio, Wayland and
+Install the toolchain, system FFmpeg, and the libraries the bundled SDL2 needs. Without the audio, Wayland and
 udev development packages SDL2 quietly configures itself without those backends, and the resulting
 build has no working sound and no gamepad hotplug:
 
 ```bash
 sudo apt-get install --no-install-recommends \
-  clang lld ninja-build cmake git glslang-tools \
+  clang lld ninja-build cmake git glslang-tools pkg-config \
+  libavformat-dev libavcodec-dev libswscale-dev libavutil-dev libavfilter-dev libswresample-dev \
   libgl1-mesa-dev libx11-dev libxcursor-dev libxext-dev libxfixes-dev \
   libxi-dev libxrandr-dev libxss-dev libxkbcommon-dev \
   libasound2-dev libpulse-dev libudev-dev libdbus-1-dev libwayland-dev wayland-protocols
@@ -192,7 +193,8 @@ cmake --install _Build/linux --prefix _Build/linux/install
 ```
 
 The install step copies the Qt libraries and plugins next to the binaries, so
-`_Build/linux/install` runs without a matching system Qt.
+`_Build/linux/install` runs without a matching system Qt. The emulator still requires
+the system FFmpeg runtime libraries matching those used to build it.
 
 As on Windows, the MSVC compiler is not used; Clang is required. `cl.exe` is rejected at configure
 time.

src/libs/avPlayer.cpp

@@ -384,6 +384,16 @@ static bool codec_is_supported_for_source(AvPlayerSourceType source_type, AVMedi
 	}
 }
 
+static const AVCodec* find_decoder(AVCodecID codec_id) {
+	const auto* decoder = avcodec_find_decoder(codec_id);
+	if (decoder == nullptr && codec_id == AV_CODEC_ID_VP9) {
+		Log::WriteToConsoleAndLog(
+		    "WARNING: AvPlayer: The game requested VP9 video, but FFmpeg has no VP9 "
+		    "decoder. Use FFmpeg with VP9 decoding enabled.\n");
+	}
+	return decoder;
+}
+
 struct PacketDeleter {
 	void operator()(AVPacket* packet) const { av_packet_free(&packet); }
 };
@@ -1064,7 +1074,7 @@ private:
 			     static_cast<int>(s->codecpar->codec_id), static_cast<uint32_t>(source_type));
 			return false;
 		}
-		if (avcodec_find_decoder(s->codecpar->codec_id) == nullptr) {
+		if (find_decoder(s->codecpar->codec_id) == nullptr) {
 			LOGF("\t decoder not found: stream=%d codec=%d\n", id,
 			     static_cast<int>(s->codecpar->codec_id));
 			return false;
@@ -1073,7 +1083,7 @@ private:
 	}
 	bool OpenCodec(int id, AVCodecContext** out) {
 		auto* s   = fmt->streams[id];
-		auto* dec = avcodec_find_decoder(s->codecpar->codec_id);
+		auto* dec = find_decoder(s->codecpar->codec_id);
 		if (dec == nullptr) {
 			LOGF("\t avcodec_find_decoder failed: stream=%d codec=%d\n", id,
 			     static_cast<int>(s->codecpar->codec_id));

src/libs/libFont.cpp

@@ -38,7 +38,12 @@
 #endif
 
 extern "C" {
+#include <libavutil/version.h>
+#if LIBAVUTIL_VERSION_MAJOR < 61
 extern const uint8_t avpriv_vga16_font[4096];
+#else
+const uint8_t* avpriv_vga16_font_get(void);
+#endif
 }
 
 namespace Libs {
@@ -950,10 +955,15 @@ static void init_image(std::array<uint8_t, FONT_BITMAP_MAX_DIM * FONT_BITMAP_MAX
 
 	const auto width  = static_cast<uint32_t>(scaled_font_width(font));
 	const auto height = static_cast<uint32_t>(scaled_font_height(font));
+#if LIBAVUTIL_VERSION_MAJOR < 61
+	const auto* vga_font = avpriv_vga16_font;
+#else
+	const auto* vga_font = avpriv_vga16_font_get();
+#endif
 
 	for (uint32_t y = 0; y < height; y++) {
 		const uint32_t src_y = std::min<uint32_t>((y * 16u) / height, 15u);
-		const uint8_t  row   = avpriv_vga16_font[code * 16 + src_y];
+		const uint8_t  row   = vga_font[code * 16 + src_y];
 		for (uint32_t x = 0; x < width; x++) {
 			const uint32_t src_x = std::min<uint32_t>((x * 8u) / width, 7u);
 			if ((row & (0x80u >> src_x)) != 0) {

src/libs/videoDec2Decoder.cpp

@@ -92,6 +92,11 @@ public:
 	[[nodiscard]] bool Initialize() {
 		const AVCodec* decoder = avcodec_find_decoder(GetAvCodecId(m_config.codec_type));
 		if (decoder == nullptr) {
+			if (m_config.codec_type == CODEC_TYPE_VP9) {
+				Log::WriteToConsoleAndLog(
+				    "WARNING: Videodec2: The game requested VP9 video, but FFmpeg has no VP9 "
+				    "decoder. Use FFmpeg with VP9 decoding enabled.\n");
+			}
 			LOGF("Videodec2: FFmpeg decoder is unavailable for codec type %u\n",
 			     m_config.codec_type);
 			return false;