Chaos based fragile watermarking algorithm for JPEG images

In this paper we propose a new fragile watermarking algorithm that provides the means to verify the integrity of JPEG images. We begin by presenting the cryptanalysis of CWSA (Chaotic Watermarking Scheme for the Authentication of JPEG Images), an existing fragile watermarking algorithm. We analyse its weaknesses and we propose a new version that is resistant to those attacks, faster and less perceptible. The proposed algorithm uses the JPEG quantized DCT coefficients and embeds the watermark information in their LSB. It uses robust chaotic generators for the generation of dynamic keys and watermarking information. One of the applications of the proposed algorithm is verifying data integrity for images transferred over the Internet.