purego-ffmpeg

purego-ffmpeg

Go bindings for the FFmpeg C API using purego — no cgo required.

Early stage — API is not stable. Currently targets FFmpeg 7.x/8.x on Linux.

Architecture

Same approach as purego-cef: a code generator parses FFmpeg C headers and produces two layers of Go code.

purego-ffmpeg/
├── cmd/ffmpeggen/          # Code generator (regex-based header parser + templates)
│   └── internal/
│       ├── parser/         # FFmpeg C header parser
│       ├── model/          # AST models
│       └── emitter/        # Go code generator with templates
├── ffmpeg/                 # Public API (generated + hand-written)
│   ├── internal/raw/       # Generated: C struct layouts + purego symbol registration
│   ├── init.go             # Hand-written: library loading, version validation
│   ├── support.go          # Hand-written: error handling, string helpers
│   └── *.go               # Generated: wrappers, enums, function bindings
└── integration/            # Integration tests (requires FFmpeg runtime)

V1 Scope

Libraries bound:

• libavutil — error codes, frame, pixel/sample formats, dictionary, logging, rationals
• libavcodec — codec context, encoder/decoder lookup, packet send/receive
• libavformat — format context, demuxing, muxing, stream info
• libswscale — video scaling/conversion
• libswresample — audio resampling

Requirements

• Go 1.26+
• FFmpeg 7.x or 8.x shared libraries (libavutil.so.60, libavcodec.so.62, etc.)
• Linux (for now)

Usage

package main

import (
    "fmt"
    "github.com/bnema/purego-ffmpeg/ffmpeg"
)

func main() {
    if err := ffmpeg.Init(); err != nil {
        panic(err)
    }

    ver := ffmpeg.FormatVersion()
    fmt.Printf("avformat version: %d.%d.%d\n", ver>>16, (ver>>8)&0xFF, ver&0xFF)
}

Building

CGO_ENABLED=0 go build ./...
CGO_ENABLED=0 go test ./ffmpeg/

Integration Tests

Requires FFmpeg shared libraries at runtime:

go test -tags=ffmpeg_integration ./integration/ -v

Regenerating Bindings

go run ./cmd/ffmpeggen/ \
  --headers-dir=/usr/include \
  --raw-dir=ffmpeg/internal/raw \
  --public-dir=ffmpeg

License

MIT