Medical Images Authentication through Repetitive Index Modulation Based Watermarking

Abstract

In this work we propose a Repetitive Index Modulation (RIM) based digital watermarking scheme for authentication and integrity verification of medical images. Exploiting the fact that many types of medical images have significant background areas and medically meaningful Regions Of Interest (ROI), which represent the actual contents of the images, the scheme uses the contents of the ROI to create a content-dependent watermark and embeds the watermark in the background areas. Therefore when any pixel of the ROI is attacked, the watermark embedded in the background areas will be different from the watermark calculated according to the attacked contents, thus raising alarm that the image in question is inauthentic. Because the creation of the watermark is content-dependent and the watermark is only embedded in the background areas, the proposed scheme can actually protect the content/ROI without distorting it.

A Heuristic Automatic and Robust ROI Detection Method for Medical Image Warermarking

“…The other solution is to ignore ROI during the watermarking process by having this part left without embedding any data and by concentrating on embedding data into the region of non interest (RONI) through reversible [14][15][16][17][18][19] or non-reversible methods [20][21][22][23][24][25][26].…”

“…For example, in [14,16,18,20,22,25,[31][32][33][34], the ROI is manually assigned by defining a rectangle box around it, and in [15,17,21,27,28], the polygonal ROI is specified manually. In automatic ROI partitioning [19,23,24,26,29,30], there are some problems which will be highlighted later in this paper.…”