ffmpeg dart code generated by dart_js_facade_gen with @ffmpeg/ffmpeg

ffmpeg.dart

@JS()
library node_modules._ffmpeg.ffmpeg.src;

import "package:js/js.dart";
import "package:js/js_util.dart" show promiseToFuture;

@JS()
external dynamic
    /*{
    writeFile: (fileName: string, binaryData: Uint8Array) => void,
    readFile: (fileName: string) => Uint8Array,
    unlink: (fileName: string) => void,
}*/
    get FS; /*type FSMethodNames = { [K in keyof typeof FS]: (typeof FS)[K] extends (...args: any[]) => any ? K : never }[keyof typeof FS];*/
/*
 Warning: Mapped types are not supported in Dart. Uses of this type will be replaced by dynamic.
type FSMethodArgs = { [K in FSMethodNames]: Parameters<(typeof FS)[K]> };
*/
/*
 Warning: Mapped types are not supported in Dart. Uses of this type will be replaced by dynamic.
type FSMethodReturn = { [K in FSMethodNames]: ReturnType<(typeof FS)[K]> };
*/
typedef dynamic LogCallback(
    dynamic /*{ type: string; message: string }*/ logParams);
typedef dynamic ProgressCallback(dynamic /*{ ratio: number }*/ progressParams);

@anonymous
@JS()
abstract class CreateFFmpegOptions {
  /// path for ffmpeg-core.js script
  external String get corePath;
  external set corePath(String v);

  /// a boolean to turn on all logs, default is false
  external bool get log;
  external set log(bool v);

  /// a function to get log messages, a quick example is ({ message }) => console.log(message)
  external LogCallback get logger;
  external set logger(LogCallback v);

  /// a function to trace the progress, a quick example is p => console.log(p)
  external ProgressCallback get progress;
  external set progress(ProgressCallback v);
  external factory CreateFFmpegOptions(
      {String corePath,
      bool log,
      LogCallback logger,
      ProgressCallback progress});
}

@anonymous
@JS()
abstract class FFmpeg {
  /// Determine whether the Core is loaded.
  external bool isLoaded();

  /// Run FS operations.
  /// For input/output file of ffmpeg.wasm, it is required to save them to MEMFS
  /// first so that ffmpeg.wasm is able to consume them. Here we rely on the FS
  /// methods provided by Emscripten.
  /// Common methods to use are:
  /// ffmpeg.FS('writeFile', 'video.avi', new Uint8Array(...)): writeFile writes
  /// data to MEMFS. You need to use Uint8Array for binary data.
  /// ffmpeg.FS('readFile', 'video.mp4'): readFile from MEMFS.
  /// ffmpeg.FS('unlink', 'video.map'): delete file from MEMFS.
  /// For more info, check https://emscripten.org/docs/api_reference/Filesystem-API.html
  external dynamic /*dynamic/*FSMethodReturn*/[Method]*/ FS/*<Method extends dynamic[keyof dynamic]>*/(
      dynamic /*Method*/ method,
      [args1,
      args2,
      args3,
      args4,
      args5]);
  external void setProgress(ProgressCallback progress);
  external void setLogger(LogCallback log);
  external void setLogging(bool logging);
  external void exit();
}

@anonymous
@JS()
abstract class _FFmpeg {
  external Promise<void> load();
  external Promise<void> run(
      [String args1, String args2, String args3, String args4, String args5]);
}

extension FFmpegExtensions on FFmpeg {
  Future<void> load() {
    final Object t = this;
    final _FFmpeg tt = t;
    return promiseToFuture(tt.load());
  }

  Future<void> run(
      [String args1, String args2, String args3, String args4, String args5]) {
    final Object t = this;
    final _FFmpeg tt = t;
    return promiseToFuture(tt.run(args));
  }
}

/// Create ffmpeg instance.
/// Each ffmpeg instance owns an isolated MEMFS and works
/// independently.
/// For example:
/// ```
/// const ffmpeg = createFFmpeg({
/// log: true,
/// logger: () => {},
/// progress: () => {},
/// corePath: '',
/// })
/// ```
/// For the usage of these four arguments, check config.js
@JS()
external FFmpeg createFFmpeg([CreateFFmpegOptions options]);

@JS()
abstract class Promise<T> {
  external factory Promise(
      void executor(void resolve(T result), Function reject));
  external Promise then(void onFulfilled(T result), [Function onRejected]);
}

Usage

Add js package to pubspec.yaml.

dependencies:
  js: ^0.6.2

Add script to index.html.

<!DOCTYPE html>
<html>
<head>
  ...
  <script src="https://unpkg.com/@ffmpeg/ffmpeg@0.10.0/dist/ffmpeg.min.js"></script>
  ...
</head>
...
</html>

And add ffmpeg.dart listed above to your project, then you can use liff.

final ffmpeg = createFFmpeg();
await ffmpeg.load();
ffmpeg.FS('writeFile', 'test.avi', await fetchFile('./test.avi'));
await ffmpeg.run('-i', 'test.avi', 'test.mp4');
await fs.promises.writeFile('./test.mp4', ffmpeg.FS('readFile', 'test.mp4'));

References

• @ffmpeg/ffmpeg
• ffmpeg.wasm/docs/api.md
• js
• js_facade_gen