An Efficient Watermarking for Protecting Signature Biometric Template

Digital watermarking is a process by which we can embed the message in security key as watermark to provide copyright protection to various text, image, audio and video documents. The Choice of optimal efficient watermarking technique is an challenging task. Many scientists have used large number of watermarks for the task which leads not only to poor performance of the algorithm but also to higher computational cost. In this paper, we propose an efficient watermarking technique which uses map based security key for offline signature which is used as an input signature biometric template. The watermark is introduced in the grayscale image by Exclusive–OR operation. The way avoids problematical computations because of its simplicity and non-fragility nature of the scheme. Experimental results show that the inserted watermark is perceptually invisible and robust to various geometric operations viz. rotation, scaling etc. and also to signal processing attacks like salt & pepper noise, speckle noise etc. The advantage of technique is that there is no reduction of image quality after watermark. Image quality constraints such as Peak Signal to Noise Ratio (PSNR), Bit Correct Ratio (BCR) are measured to validate the proposed method.