Fragile Watermarking Using Finite Field Trigonometrical Transforms

TL;DR

This paper introduces a novel fragile watermarking scheme using finite field cosine and Hartley transforms, enabling tamper detection and authentication with high accuracy and invisibility.

Contribution

It presents a new watermarking method based on finite field transforms, enhancing authentication and tamper detection in images with error-free calculations.

Findings

Watermarked images are perceptually invisible.

The scheme allows precise tamper localization.

Finite field transform choice affects watermark invisibility.

Abstract

Fragile digital watermarking has been applied for authentication and alteration detection in images. Utilizing the cosine and Hartley transforms over finite fields, a new transform domain fragile watermarking scheme is introduced. A watermark is embedded into a host image via a blockwise application of two-dimensional finite field cosine or Hartley transforms. Additionally, the considered finite field transforms are adjusted to be number theoretic transforms, appropriate for error-free calculation. The employed technique can provide invisible fragile watermarking for authentication systems with tamper location capability. It is shown that the choice of the finite field characteristic is pivotal to obtain perceptually invisible watermarked images. It is also shown that the generated watermarked images can be used as publicly available signature data for authentication purposes.