Flutter Steganograph

Flutter Steganograph is a digital image encoding package that embeds a message (text or image) into a cover image/text using the least significant bit (LSB) technique with minimal alteration to the original cover image/text.

Installation 🛸

Add flutter_steganograph to your pubspec.yaml:

dependencies:
  flutter_steganograph: ^0.1.0

Usage 📦

Importing the Package

import 'package:flutter_steganograph/flutter_steganograph.dart';

Embed a secret text into a cover text ♟️

Embeds a secret text inside a cover text using zero-width characters. Returns a string with the secret message embedded inside cover text, invisible to normal readers.

import 'package:flutter_steganograph/src/flutter_steganograph.dart';

final steganograph = Steganograph();

String embeddedText = steganograph.embedTextInText(
    coverText: 'cover text sample', 
    secretMessage: 'super secret text to hide',
    );
print(embeddedText);

Extract the secret text from cover text ♖

Extracts a text message embedded in a text using zero-width characters. Returns the extracted secret message. If no secret message is found, returns a message indicating this.

import 'package:flutter_steganograph/src/flutter_steganograph.dart';

final steganograph = Steganograph();

String secretText = steganograph.extractTextFromText(
    encodedText: 'cover text sample',
    );
print(secretText);

Embed a text into an image 🔩

Embeds a text string into an image. Optional saveImage argument to download embedded image to gallery. Returns the encoded bytes -> Uint8List.

import 'package:image/image.dart' as dImage;
import 'package:flutter_steganograph/src/flutter_steganograph.dart';

final steganograph = Steganograph();
final coverImage = dImage.decodePng(File('/cover_image.png').readAsBytesSync())!;

final embeddedTextImage = steganograph.embedText(
    image: coverImage, 
    text: 'super secret text',
    saveImage: true
    );
// to covert to material image
Image.memory(embeddedTextImage);

Extract the secret text from the encoded image 🔬

Extracts a secret text string from an encoded image. Returns the extracted secret String

import 'package:image/image.dart' as dImage;
import 'package:flutter_steganograph/src/flutter_steganograph.dart';

final steganograph = Steganograph();
final encodedImage = dImage.decodePng(File('/encoded_image.png').readAsBytesSync())!;
int secretLength = secretText.length;

String secretText = steganograph.extractText(
    image: encodedImage, 
    length: secretLength,
    );

Embed a secret Image inside a cover image 🖼️

Embed/encode a secret image inside a cover image. secret image dimensions are smaller than cover image dimensions. Returns the embedded bytes -> Uint8List of encoded image.

import 'package:image/image.dart' as dImage;
import 'package:flutter_steganograph/src/flutter_steganograph.dart';

final steganograph = Steganograph();
final coverImage = dImage.decodePng(File('/cover_image.png').readAsBytesSync())!;
final secretImage = dImage.decodePng(File('/secret_image.png').readAsBytesSync())!;

Uint8List embeddedImage = steganograph.embedImage(
        coverImage: coverImage,
        secretImage: secretImage,
      );
//to covert to material image
Image.memory(embeddedImage);

Extract the secret Image from an encoded image 🧮

decode a secret image from the encoded image. Returns the embedded bytes -> Uint8List of secret image.

import 'package:image/image.dart' as dImage;
import 'package:flutter_steganograph/src/flutter_steganograph.dart';

final steganograph = Steganograph();
final encodedImage = dImage.decodePng(File('/encodedImage_image.png').readAsBytesSync())!;
int secretImageHeight;
int secretImageWith;

Uint8List extractedImage = steganograph.extractImage(
        embeddedImage: encodedImage!,
        secretWidth: secretImageHeight,
        secretHeight: secretImageHeight,
      );
//to covert to material image
Image.memory(extractedImage);

Coming soon

encryption 🔒 of secret text and image

Contribution

Feel free to open pull requests that improve the quality of images or performance of the library. Any bugs should be submitted to Issues

Libraries

flutter_steganograph