flutter_bicubic_resize library

Fast, consistent bicubic image resizing for Flutter.

This library provides native C-based bicubic image resizing that produces identical results on iOS and Android. Uses Catmull-Rom interpolation (same as OpenCV and PIL/Pillow).

Features

• 100% Native C performance (stb_image + stb_image_resize2)
• Identical results on iOS and Android
• Bicubic interpolation with multiple filter options
• Full native pipeline: decode -> resize -> encode
• RGB and RGBA support
• JPEG and PNG support with alpha channel preservation

Quick Start

import 'package:flutter_bicubic_resize/flutter_bicubic_resize.dart';

// Resize JPEG
final resized = BicubicResizer.resizeJpeg(
  jpegBytes: originalBytes,
  outputWidth: 224,
  outputHeight: 224,
);

// Resize PNG
final resizedPng = BicubicResizer.resizePng(
  pngBytes: originalBytes,
  outputWidth: 224,
  outputHeight: 224,
);

Available Filters

• BicubicFilter.catmullRom - Default. Same as OpenCV/PIL. Best for ML.
• BicubicFilter.cubicBSpline - Smoother, more blurry.
• BicubicFilter.mitchell - Balanced between sharp and smooth.

See the API documentation for detailed usage information.

Classes

BicubicResizer

Enums

BicubicFilter

Available bicubic filter types

CropAnchor

Crop anchor positions

CropAspectRatio

Crop aspect ratio modes

EdgeMode

Edge handling modes for resize operations

ImageFormat

Supported image formats for resize operations

Exceptions / Errors

UnsupportedImageFormatException

Exception thrown when an unsupported image format is detected.