Image Authentication based on Histogram Shifting method using Arnold’s Cat Map

1Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI)    2Chennai Mathematical Institute (CMI)   

Abstract

Digital watermarking is a crucial technique for embedding and extracting hidden information in digital media, including medical images. Image authentication plays a critical role in ensuring the integrity and authenticity of digital medical images, which are essential for accurate diagnosis, treatment planning, and research. The project focuses on the development of a robust watermarking algorithm for images authentication using methods, including techniques like Haar Transform, Histogram Shifting, Arnold’s Cat Map. The methods aim to embed an imperceptible watermark into images, which can later be extracted to verify the authenticity and integrity of the images.

Project Overview

This project demonstrates a reversible data hiding technique for image authentication. It combines Histogram Shifting with Arnold's Cat Map to embed watermarks securely without significant image degradation.

  • Watermark embedding & extraction through reversible data hiding.
  • Histogram Shifting for imperceptible watermarking.
  • Arnold's Cat Map scrambling for enhanced security.
  • Performance metrics: PSNR, SSIM, and NCC.
  • Resistance to common image processing attacks.

Methodology

Descriptive alt text
2D DWT

Embedding Process

  1. Convert the image using Haar Wavelet Transform.
  2. Divide the image into LL, HL, LH, and HH sub-bands.
  3. Scramble the watermark with Arnold's Cat Map.
  4. Encode the watermark with SHA-256 hashing.
  5. Embed the scrambled watermark in the HH sub-band and the hash in the LL sub-band using Histogram Shifting.
  6. Perform the inverse Haar Transform to reconstruct the stego image.

Extraction Process

  1. Apply Haar Transform to the stego image to retrieve LL and HH components.
  2. Recover the watermark from HH and extract the SHA-256 hash from LL.
  3. Reverse Arnold's Cat Map to obtain the original watermark.
  4. Verify the watermark integrity using SHA-256 validation.

Result

Results after embedding without attack on samples images from USC SIPI database
Cover Image Secret Image PSNR MSE NCC SHA
airplane.tiffsplash.tiff59.534160.0723881TRUE
Barbara.tifsplash.tiff61.207610.049241TRUE
elaine.tiffsplash.tiff61.149790.04991TRUE
fishingboat.tiffsplash.tiff60.747990.0547371TRUE
Goldhill.tifsplash.tiff61.512820.0458981TRUE
house.tiffsplash.tiff60.318650.0604251TRUE
lena.tiffsplash.tiff60.402530.0592691TRUE
peeper.tiffsplash.tiff61.35440.0476041TRUE
sailboat.tiffsplash.tiff61.061720.0509221TRUE
tank.tiffsplash.tiff61.377090.0473561TRUE