A Novel Large Capacity Image Hiding Method Based on the Orthogonal Chaotic Sequences

In this paper, a new scheme of hiding multiple secret images into the same cover image is proposed based on the orthogonal chaotic sequences and wavelet transform. Firstly, the secret images are spreaded spectrum with orthogonal pseudo-random chaotic sequences into the spreaded spectrum signals, where chaotic sequences are filtered according to their self-correlation and mutual-correlation characteristics, and they are also utilized as the keys while recovering the secret images because of their sensitivity to the initial values. Then, the secret images can be embedded into the same cover image in wavelet domain simultaneously because all the spreaded secret images are orthogonal. Different from the traditional methods, this method can not only be better in terms of imperceptibility, security and robustness, but also improve the information hidden capacity of a cover image. The experimental results show that the proposed method is able to achieve robustness, imperceptibility and authenticity in image hiding.