yuv_ffi #

yuv_ffi is a Flutter/Dart package for high-performance image processing on YUV/BGRA frames using native C + FFI.

Features #

• YUV format conversions (i420, nv21, bgra8888)
• Crop, rotate, flip
• Grayscale, black/white, negate
• Mean/box/Gaussian blur
• Plane-based API with row/pixel stride support
• In-memory save/load helpers for frame serialization

Important format note (nv21) #

In this project, the nv21 label is intentionally used for a buffer with UV chroma order (practically closer to NV12), not classic VU NV21.

This is a deliberate internal contract.
When integrating with external camera/codec pipelines, swap U/V if needed.

Installation #

From pub.dev:

dependencies:
  yuv_ffi: ^0.1.0

Or from Git:

dependencies:
  yuv_ffi:
    git:
      url: https://github.com/Anfet/yuv_ffi.git

Quick start #

import 'package:yuv_ffi/yuv_ffi.dart';

final image = YuvImage.i420(1280, 720);
image.fromRgba8888(rgbaBytes); // rgbaBytes.length must be width * height * 4

final preview = image
    .rotate(YuvImageRotation.rotation90)
    .grayscale()
    .toBgra8888();

Public API (Dart) #

Exports from package:yuv_ffi/yuv_ffi.dart:

• YuvImage
• YuvPlane
• YuvFileFormat
• YuvImageRotation
• YuvImageWidget

Main constructors:

• YuvImage.i420(width, height, ...)
• YuvImage.nv21(width, height, ...)
• YuvImage.bgra(width, height, ...)

Platform support #

• Android: native FFI
• iOS: native FFI
• macOS: native FFI
• Windows: native FFI
• Linux: native FFI
• Web: package builds, but YuvImage processing is currently a stub/no-op implementation (placeholder only)

TODO #

• Implement a real web backend for YuvImage operations.
• Replace current web stub behavior (no-op placeholders, no native-quality processing).

Build notes #

Native code is in src/ and is built as a shared library per platform:

• Android/Linux: libyuv_ffi.so
• Windows: yuv_ffi.dll
• Apple platforms: platform-specific dynamic/static linkage via plugin build setup

Generated bindings #

Do not edit lib/src/functions/bindings/yuv_ffi_bingings.dart manually.
It is generated via ffigen from src/yuv_ffi.h using ffigen.yaml.

Regenerate with:

flutter pub run ffigen --config ffigen.yaml

License #

MIT