An Effective chaos-based image watermarking scheme using fractal coding

AbstractThe image watermarking technology is a technique of embedding hidden data in an original image. In this paper, a new watermarking method for embedding watermark bits based on Chaos-Fractal Coding is given. A chaotic signal is defined as being deterministic, pseudo periodic and presenting sensitivity to initial conditions. Combining a chaos system with Fractal Coding plays an important role in the security, invisibility and capacity of the proposed scheme. The main idea of the new proposed algorithm for coding is to determine a set of selective blocks for steady embedding. Simulation results show that the CFC algorithm (Chaos-Fractal Coding) has a confident capacity. The embedding technique that proposed in this paper is quite general, and can be applied to the extracting scheme with demanded changes

Fixed point in fractal image compression as watermarking

Conventional approaches to embedding digital watermarks [1] are done by adjusting spatial pixel values or frequency coefficients. We propose a novel way to achieve attack detection by calculating the image's fractal compression fixed point which is an approximation to the original image. After such transformation the fixed point image survives fractal image compression and is extremely sensitive to manipulations. A method to embed digital signatures into the fixed point is also presented in order to provide authentication