ffmpeg-m

FFmpeg as C++ modules for mcpp — built entirely from source, API unchanged.

import std;
import ffmpeg.av;   // the whole FFmpeg surface, Python `import av` style

int main() {
    AVFormatContext* fmt { nullptr };
    avformat_open_input(&fmt, "video.mp4", nullptr, nullptr);
    // ... the exact same C API you already know — just no #include
}

• Source build, no CMake/configure at build time. The compat.ffmpeg index package carries the frozen configure snapshot + exact source list; mcpp compiles all of FFmpeg 8.1.2 (2124 .c + 157 NASM .asm, x86 SIMD included) directly — cold build ≈ 21 s on 32 cores. This repo is only the thin module layer.
• API and habits unchanged. Every public function, type, enum, and enum constant is re-exported under its upstream global name (avcodec_open2, AVFrame, AV_CODEC_ID_H264, …).
• Full-feature profile. All internal components are on: 600+ decoders, 350+ demuxers, encoders, muxers, filters, swscale/swresample — hermetic (no host libraries probed), LGPL-2.1+ clean.

Modules

import	contents
ffmpeg.av	everything below (recommended default)
ffmpeg.avutil / ffmpeg.avcodec / ffmpeg.avformat / ffmpeg.avfilter / ffmpeg.avdevice / ffmpeg.swscale / ffmpeg.swresample	one library each; dependencies are re-exported (import ffmpeg.avformat; brings avcodec + avutil)
ffmpeg	lib-root alias of ffmpeg.av

Macros and header-only helpers

Named modules cannot export macros or static inline helpers. Everything with linkage comes from the import; for the macro spellings (AVERROR, AV_NOPTS_VALUE, AVIO_FLAG_WRITE, MKTAG, …) and inline utilities (av_q2d, av_clip, …) add the optional side header before the import:

#include <ffmpeg-m/macros.h>
import ffmpeg.av;

C-only compound-literal macros get C++ replacements exported from the module: av_err2str → av_err2string(err).c_str(), av_ts2str → av_ts2string, av_ts2timestr → av_ts2timestring, av_fourcc2str → av_fourcc2string.

Using

[dependencies]
ffmpeg = "0.0.1"

Or start from the template: mcpp new myplayer --template ffmpeg (decode skeleton). Examples: examples/probe (no input needed), examples/decode_frames.

Validate the package: mcpp build && mcpp test (self-contained encode→decode roundtrip + API-surface tests).

Layout

src/*.cppm            module layer (GMF include + export using)
src/gen_exports/      generated export lists + skip reports
include/ffmpeg-m/     optional macros side header
tools/                fetch_upstream.sh (pinned official tarball),
                      gen_exports.py (headers → export lists)
templates/  examples/ project template + runnable consumers

Upstream sources are NOT vendored: they reach consumers through the compat.ffmpeg mcpp-index package (official ffmpeg.org tarball, GLOBAL + CN mirror, sha256-pinned). Its descriptor — config snapshot inlined as generated_files plus the make -n source list — is maintained in mcpp-index (tools/compat-ffmpeg/). FFmpeg bump: bump compat.ffmpeg there first, then update the pin in tools/fetch_upstream.sh, run python3 tools/gen_exports.py, and review the export-list diffs.

Notes

• Hardware-acceleration headers that need external SDKs (libavutil/hwcontext_cuda.h, VAAPI, …) are not part of the module export surface; with the SDK present, include them textually next to the import.
• Optional variants (external codecs, GPL components, slim profiles) are planned as mcpp features backed by per-profile config snapshots.
• License: this wrapper repo is MIT; the upstream sources arrive via compat.ffmpeg under LGPL-2.1-or-later (no --enable-gpl/nonfree components); source distribution satisfies LGPL relinking by construction.