// Register a callback for frame‑ready events using FrameCallback = std::function<void(const Frame&)>; void setFrameCallback(MediaHandle, FrameCallback); private: // Implementation hidden – pImpl idiom to keep ABI stable struct Impl; std::unique_ptr<Impl> pImpl_; ;
int main() mkv::EngineConfig cfg; cfg.videoBackend = mkv::EngineConfig::Backend::Vulkan; cfg.decoder = mkv::EngineConfig::Decoder::Hybrid; mkv::CinemaEngine engine(cfg); mkvcinemas.h
// Query state PlaybackState state(MediaHandle h) const noexcept; // Register a callback for frame‑ready events using
// Target framerate (e.g., 24, 30, 60) unsigned int targetFps = 60; quality trade‑offs, making mkvcinemas
Why it mattered : By exposing only a thin, interface, the header let developers allocate and destroy the engine without worrying about memory leaks. The internal Impl could evolve (add Vulkan, DirectX12, or Apple‑Metal back‑ends) while the public API stayed constant. 2.2 struct EngineConfig struct EngineConfig // Choose rendering backend (auto‑detect by default) enum class Backend Auto, OpenGL, Vulkan, DirectX12, Metal ; Backend videoBackend = Backend::Auto;
// Custom allocator (optional) std::function<void*(std::size_t)> alloc = nullptr; std::function<void(void*)> dealloc = nullptr; ; Why it mattered : EngineConfig gave the control over performance vs. quality trade‑offs, making mkvcinemas.h suitable for everything from low‑power ARM tablets to high‑end 8‑K home theaters. 2.3 struct Frame struct Frame const uint8_t* data; // Pointer to raw pixel data (RGB, YUV, etc.) std::size_t stride; // Bytes per row uint32_t width, height; PixelFormat fmt; // Enum: RGB24, YUV420, etc. std::chrono::nanoseconds pts; // Presentation timestamp bool isKeyFrame; ; Why it mattered : By handing out a const view of the frame, mkvcinemas.h let applications render directly into a GPU texture or write to a custom compositor without copying. The pts field ensured perfect synchronization with audio. Chapter 3 – The First Test: “Midnight at the Oasis” Mara invited her friends— Leo (a graphics guru), Tara (audio engineer), and Sam (the UI designer)—to a demo night. They compiled a minimal program:
// Load a media container (MKV, MP4, AVI, …) MediaHandle load(const std::filesystem::path& file);