Biblio

The paper proposes a method for image content recovery based on digital watermarking. Existing image watermarking systems detect the tampering and can identify the exact positions of tampered regions, but only a few systems can recover the original image content. In this paper, we suggest a method for recovering the regions of interest (ROIs). It embeds the semi-fragile watermark resistant to JPEG compression (for the quality parameter values greater than or equal to the predefined threshold) and such local tamperings as splicing, copy-move, and retouching, whereas is destroyed by any other image modifications. In the experimental part, the performance of the method is shown on the road traffic JPEG images where the ROIs correspond to car license plates. The method is proven to be an efficient tool for recovering the original ROIs and can be integrated into any JPEG semi-fragile watermarking system.

Cryptography is a widespread technique that maintains information security over insecure networks. The symmetric encryption scheme provides a good security, but the key exchange is difficult on the other hand, in the asymmetric encryption scheme, key management is easier, but it does not offer the same degree of security compared to symmetric scheme. A hybrid cryptosystem merges the easiness of the asymmetric schemes key distribution and the high security of symmetric schemes. In the proposed hybrid cryptosystem, Serpent algorithm is used as a data encapsulation scheme and Elliptic Curve Cryptography (ECC) is used as a key encapsulation scheme to achieve key generation and distribution within an insecure channel. This modification is done to tackle the issue of key management for Serpent algorithm, so it can be securely used in multimedia protection.