video_forge 1.0.0

High-performance Rust video processing engine for Flutter. Hardware-accelerated video transcoding, frame-accurate previews, audio mixing, and fast thumbnail generation powered by FFmpeg. Low-level eng [...]

video_forge

pub package License

Open-source project maintained by the community. Found a bug or want to contribute? PRs and issues are welcome.

High-performance Rust video processing engine for Flutter — hardware-accelerated transcoding, frame-accurate previews, audio mixing, and fast thumbnail generation. Powered by native FFmpeg with platform codecs (MediaCodec, VideoToolbox).

Note

This is a low-level engine — raw FFI bindings to Rust + FFmpeg. Provides hardware-accelerated transcoding, frame-accurate previews, audio mixing, and thumbnail generation.

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Platform Support

Platform	Status
Android	Tested (SDK 24+, MediaCodec)
iOS	Tested (13.0+, VideoToolbox)
macOS	Tested (10.15+, VideoToolbox)
Windows	In progress
Linux	In progress
Web	Not supported

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Quick Start

import 'package:video_forge/video_forge.dart';

// Call once at app startup
await initialize();

// Probe video metadata
final info = await getMediaInfo(path: '/path/to/video.mp4');
print('${info.width}x${info.height} ${info.durationMs}ms');

// Compress with progress stream
final progress = startCompress(options: CompressOptions(
  inputPath: '/path/to/video.mp4',
  outputPath: '/path/to/output.mp4',
));
await for (final event in progress) {
  print('${event.phase}: ${event.fps} fps');
}

// Extract a thumbnail
final thumbPath = await thumbnail(options: ThumbnailOptions(
  inputPath: '/path/to/video.mp4',
  positionMs: 1500,
  outputPath: '/path/to/thumb.jpg',
));

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What You Can Do

• Video transcoding — Async compression with hardware acceleration (MediaCodec, VideoToolbox). Phase-based progress reporting with FPS and ETA.
• Metadata probing — Fast MP4 inspection (mp4parse) with FFmpeg fallback. Dimensions, duration, framerate, codecs, rotation, Dolby Vision markers.
• Thumbnails & filmstrips — Frame-accurate single/batch extraction with optimized GOP seek. Output to files or in-memory byte arrays.
• Frame-accurate previews — Decode frames to raw RGBA or Apple zero-copy CVPixelBuffer. No temp files.
• Audio mixing — Mix external audio tracks with source video. Per-track offsets, durations, and volume.
• Overlay burn-in — Composite PNG overlays (watermarks, stickers) onto video frames with fade transitions.
• Playback sessions — Decoder-driven playback with seek, play/pause, and custom frame-rate ticks.
• Buffer pool — Recycled byte vectors to eliminate allocations during scrub sessions.

For the full API, see the Dart API reference.

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Pros & Cons

Pros	Cons
Hardware-accelerated video processing	No web support
Async jobs with progress updates	FFmpeg libraries add significant app size
Android, iOS, macOS (Windows & Linux in progress)	FFmpeg setup can be involved (especially macOS VT)
Frame-accurate previews without temp files	FFmpeg is LGPL — requires license notice in your app
Built-in audio mixing for timeline editors	Needs native build toolchain, not pure Dart
Fast thumbnail and filmstrip generation	Large binary from bundled video codecs

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App Size

The package includes native Rust code plus external FFmpeg libraries:

Component	Est. Size
Rust engine (transcoding, preview, thumbnails, audio mix)	~5–8 MB
FFmpeg libraries (libavcodec, libavformat, libavfilter, libswscale)	~15–30 MB
Total	~20–38 MB

FFmpeg is the dominant cost. The Rust engine itself is modest — most of the weight comes from video/audio codec libraries. Android uses App Bundles, so users only download their device's ABI.

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Installation

flutter pub add video_forge

Prerequisites:

• Rust toolchain on your development machine
• FFmpeg libraries (libavcodec, libavformat, libavfilter, libswscale) on your linker path
• macOS with VideoToolbox: Build FFmpeg with VT support
• Android: NDK configured in local.properties; install Android Rust targets:

  rustup target add aarch64-linux-android armv7-linux-androideabi \
    x86_64-linux-android i686-linux-android
  

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More Examples

Batch thumbnails (filmstrip)

final result = await batchThumbnails(options: BatchThumbnailOptions(
  inputPath: '/path/to/video.mp4',
  positionsMs: [0, 5000, 10000, 15000],
  outputDir: '/tmp/thumbs',
));

// Or in-memory for UI display
final frames = await batchThumbnailBytes(options: BatchThumbnailBytesOptions(
  inputPath: '/path/to/video.mp4',
  positionsMs: [0, 5000, 10000, 15000],
));

Frame-accurate preview decode

final frame = await decodePreviewFrameRgba(
  inputPath: '/path/to/video.mp4',
  positionMs: BigInt.from(4200),
  maxEdge: 720,
);
// frame.width, frame.height, frame.data (RGBA bytes)

Cancel a running job

final jobId = /* from startCompress */;
await cancelJob(jobId: jobId);
print('Active jobs: ${await activeJobCount()}');

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Contributing

This package is part of the MediaForge monorepo. Issues and pull requests are welcome on GitHub.

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Links

• GitHub Repository
• Issue Tracker