facsimile 1.0.0

Removes the paper background from photos of stamps and signatures to make transparent facsimiles for documents, printing or e-signing.

example/lib/main.dart

import 'package:facsimile/facsimile.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Facsimile Demo',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: const MyHomePage(title: 'Facsimile Demo'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  Uint8List? _original;
  Uint8List? _processed;
  bool _loading = false;
  String? _error;

  Future<void> _loadAndProcess() async {
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      final buf = await rootBundle.load('assets/img1_137.jpg');
      final bytes = buf.buffer.asUint8List();
      final processed = const Facsimile().removeBackground(bytes);
      setState(() {
        _original = bytes;
        _processed = processed;
      });
    } catch (e) {
      setState(() {
        _error = e.toString();
      });
    } finally {
      setState(() {
        _loading = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    const size = Size(320, 320);
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      floatingActionButton: FloatingActionButton.extended(
        onPressed: _loading ? null : _loadAndProcess,
        icon: const Icon(Icons.auto_fix_high),
        label: const Text('Make facsimile'),
      ),
      body: Center(
        child: _loading
            ? const CircularProgressIndicator()
            : _error != null
                ? Padding(
                    padding: const EdgeInsets.all(16),
                    child: Text(_error ?? 'Error'),
                  )
                : Wrap(
                    spacing: 16,
                    crossAxisAlignment: WrapCrossAlignment.center,
                    children: [
                      if (_original != null)
                        _Preview(label: 'Original', image: _original!, size: size),
                      if (_processed != null) ...[
                        _Preview(
                          label: 'Facsimile',
                          image: _processed!,
                          size: size,
                        ),
                        _Preview(
                          label: 'Stamped on green',
                          image: _processed!,
                          size: size,
                          showOnColor: Colors.green,
                        ),
                      ] else
                        const Padding(
                          padding: EdgeInsets.all(16),
                          child: Text(
                            'Press the button to load the sample '
                            'signature photo and remove its background.',
                          ),
                        ),
                    ],
                  ),
      ),
    );
  }
}

class _Preview extends StatelessWidget {
  const _Preview({
    required this.label,
    required this.image,
    required this.size,
    this.showOnColor,
  });

  final String label;
  final Uint8List image;
  final Size size;
  final Color? showOnColor;

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        Text(label),
        const SizedBox(height: 4),
        Container(
          width: size.width,
          height: size.height,
          color: showOnColor,
          child: Image.memory(image, fit: BoxFit.contain),
        ),
      ],
    );
  }
}