In order to improve the problems of traditional one-dimensional chaotic mapping, such as small chaotic interval, discontinuous chaotic interval, simple chaotic behavior and low initial value sensitivity, a two-dimensional chaotic system based on 1D-LSE (Logistic self-embedding) chaotic mapping is proposed and further extended to a three-dimensional. Taking the improved two-dimensional chaotic system as an example, various performance indicators, such as the Lyapunov exponent, bifurcation diagram, sensitivity to initial values, bit change rate, and sequence randomness, are analyzed. The experimental simulation results show that the proposed two-dimensional chaotic system has a continuous chaotic interval, a larger chaotic interval, better performance in generating random sequences, higher sensitivity to initial values, and more complex chaotic characteristics.

A blind-watermark algorithm is proposed for protecting MP3 copyright in DWT and DCT mixed domain,it is based on characteristics of MP3 compression attack and imagination concealment.In order to improve the security of watermarking system,chaos is introduced in audio frequency watermark algorithm,the binary image comprised by copyright and key is encrypted by chaotic sequence and embedded in the original signal's frequency domain.The watermark signal can be extracted without the original audio signal and the algorithm is a blind-watermark algorithm.Simulation results show that the algorithm is robust and security.