ffipeg_builder library

Builder to generate Dart FFI bindings to FFmpeg with a simple library annotation.

ffipeg and ffipeg_builder allow you to automatically generate FFI bindings to FFmpeg by using the @FFmpegGen annotation on any Dart library in your project.

The builder has two steps:

A fast step which generates a configuration JSON file for FfiGen in the cache;
A slow step which runs FfiGen only when the configuration changes.

To use this package, add the following dependencies to your pubspec.yaml:

ffipeg
ffi
ffipeg_builder (under dev_dependencies)
build_runner (under dev_dependencies)

Then, annotate a library (anywhere in your project) with @FFmpegGen, specifying the FFmpeg functions, structs, enums, and other elements you want to include or exclude. The bindings will be generated automatically when you run the build process.

Finally, run dart run build_runner build -d or dart run build_runner watch -d in your project.

A my_library.ffipeg.dart file will be generated with the FFI bindings, e.g. if your library is named my_library.dart.

Example usage (all fields are optional unless required by your system config; please review annotation docs):

@FFmpegGen(
  versionSpec: '>=7.1 <8.0',
  headerPaths: {'/usr/local/include', '/opt/ffmpeg/include'},
  llvmPaths: {'/usr/local/opt/llvm', '/opt/llvm'},
  libraries: {FFmpegLibrary.avCodec, FFmpegLibrary.avFormat},
  excludeAllByDefault: true,
  functions: FFInclude({
    'av_compare_ts',
    'av_interleaved_write_frame',
    'av_log_set_level',
  }),
  structs: FFInclude({'AVFormatContext', 'AVIOContext', 'AVPacket'}),
  enums: FFInclude({'AVMediaType'}),
  unnamedEnums: FFInclude({'UNNAMED_ENUM'}),
  unions: ffAllowAll,
  globals: ffDenyAll,
  macros: FFInclude({'AVIO_FLAG_WRITE', 'AV_NOPTS_VALUE'}),
  typedefs: ffAllowAll,
  className: 'FFmpegBindings',
  excludeHeaders: {'libavcodec/jni.h', ...defaultExcludeHeaders},
)
library;

import 'my_library.ffipeg.dart'; // Use the generated bindings

The generated file can be imported and used in your project, allowing direct access to the FFmpeg C API through Dart's FFI (Foreign Function Interface).

For a full working example, please see the ffipeg_muxer package.

ffipeg_builder library

Functions

ffipeg_builder package

ffipeg_builder library