Reversible Image Watermarking for Health Informatics Systems Using Distortion Compensation in Wavelet Domain

TL;DR

This paper presents a reversible watermarking method for medical images that increases embedding capacity and reduces distortion by using a novel distortion compensation approach in the wavelet domain.

Contribution

It introduces a new distortion compensation technique in wavelet-based reversible watermarking to enhance capacity and minimize image distortion in medical images.

Findings

Maximum capacity of 1.5 BPP achieved

Method outperforms state-of-the-art in capacity and distortion

Effective on various medical image types

Abstract

Reversible image watermarking guaranties restoration of both original cover and watermark logo from the watermarked image. Capacity and distortion of the image under reversible watermarking are two important parameters. In this study a reversible watermarking is investigated with focusing on increasing the embedding capacity and reducing the distortion in medical images. Integer wavelet transform is used for embedding where in each iteration, one watermark bit is embedded in one transform coefficient. We devise a novel approach that when a coefficient is modified in an iteration, the produced distortion is compensated in the next iteration. This distortion compensation method would result in low distortion rate. The proposed method is tested on four types of medical images including MRI of brain, cardiac MRI, MRI of breast, and intestinal polyp images. Using a one-level wavelet transform, maximum capacity of 1.5 BPP is obtained. Experimental results demonstrate that the proposed method is superior to the state-of-the-art works in terms of capacity and distortion.