docs_auto_sign

A Flutter package that automatically detects signature fields in a PDF and stamps a PNG signature image onto them.

Features

  • 📄 Automatically finds target words (e.g. signature, sign) in a PDF
  • 🖊️ Stamps a PNG signature image above each found word
  • 📦 Returns signed PDF as Uint8List
  • ⚙️ Fully customizable — target words, signature size

Installation

Add this to your pubspec.yaml:

dependencies:
  docs_auto_sign: ^0.0.1

Then run:

flutter pub get

Usage

import 'package:docs_auto_sign/docs_auto_sign.dart';

final result = await AutoSignService.applySignatureToPdf(
  originalPdfFile: myPdfFile,         // File
  signatureBytes: mySignaturePng,     // Uint8List (PNG)
  targetWords: ['signature', 'sign'], // words to find
);

print('Total signatures added: ${result.totalSignaturesAdded}');
print('Pages modified: ${result.pagesModified}');

// result.signedPdfBytes → Uint8List (signed PDF)

Parameters

Parameter Type Required Description
originalPdfFile File The original PDF file
signatureBytes Uint8List PNG signature image bytes
targetWords List<String> Words to search and sign
signatureWidth double Default: 120.0
signatureHeight double Default: 50.0

Result

Property Type Description
signedPdfBytes Uint8List Signed PDF bytes
totalSignaturesAdded int Total signatures stamped
pagesModified List<int> Pages that were modified

License

MIT

Libraries

docs_auto_sign