Abstract
The widely available multimedia editing tools and their large reconstruction capabilities make digital multimedia content more sensitive to malicious tampering and manipulations. Therefore, ensuring digital image integrity has become a crucial issue. Watermarking became a popular technique for image authentication. The goal of this paper is to propose a new semi-fragile watermarking scheme for image authentication, localization, and recovery, by using two different watermarks jointly. The embedded information watermark for content recovery is computed from discrete wavelet transform (DWT) approximation coefficients of second level decomposition of the original image and compressed by using Data Representation through Combination (DRC) in order to reduce watermark payload. On another hand, authentication watermark used for both authentication and localization of image tampering is computed by using the block-based watermarking algorithm. Three pseudo-random maps are generated in order to improve the security of the proposed scheme against local attack. Both watermarks are embedded into approximation sub-band of the first wavelet decomposition. Experimental results show that our proposed approach has not only an extremely high accuracy of tampering localization but also a relatively very high recovery rate. Besides, the scheme is able to detect perfectly the difference between malicious attacks and non-malicious attacks such as JPEG compression.