lumen-engine-ffmpeg

lumen-engine-ffmpeg is Lumen's lower-level FFmpeg integration crate. It wraps the FFmpeg C APIs needed for demuxing, decoding, encoding, muxing, and GPU video frame interop.

This crate is experimental. The API is built around Lumen's current renderer and server needs, and may change.

Platform Notes

Supported render/media targets today are:

• Linux with Vulkan and CUDA/NVENC for GPU interop and hardware encode paths.
• macOS with Metal and VideoToolbox-oriented frame/encode paths.

CPU decode/encode helpers exist, but Lumen's production renderer is GPU-first and should be treated as requiring GPU-capable machines.

Features

• avcodec, avformat, swresample, swscale: FFmpeg component features enabled by default.
• metal: enables CoreVideo/Metal interop types used on macOS.
• vulkan: enables Vulkan video frame interop types.
• cuda: enables CUDA interop via cudarc and NVENC helpers. Kernel sources live under crates/ffmpeg/cuda/ and are compiled to PTX with nvcc at build time (requires the CUDA toolkit on Linux). Override the target with LUMEN_CUDA_ARCH (default sm_50) or the compiler with CUDA_NVCC.
• build-ffmpeg: asks ffmpeg-sys-next to build FFmpeg.
• gpl: enables GPL FFmpeg build licensing through ffmpeg-sys-next.
• nonfree: enables nonfree FFmpeg build licensing through ffmpeg-sys-next.

Development

cargo check -p lumen-engine-ffmpeg
cargo test -p lumen-engine-ffmpeg
cargo check -p lumen-engine-ffmpeg --features vulkan,cuda