How to protect secret information is a most important issue in military technology. In this paper, a (p,n) secret sharing method using Blakley's concept is proposed to protect the security of secret images. Even though enemies know p−1 of n shadow images, they cannot obtain any information about the secret image. Only p or more than p shadow images can reconstruct it. Experimental results show that the proposed method has the advantage of smaller shared images, which can greatly reduce the storage space.
A copyright protection technique without using the original image in the process of copyright verification is demanded in most applications. In addition, robustness, imperceptibility, security, and unambiguity are also essential requirements for a copyright protection technique. In this paper, a robust copyright protection scheme for digital images, based on the low-band characteristic, is proposed to meet these requirements. Experimental results show that the proposed scheme not only can clearly verify the copyright of the digital images, but also is more robust than existing schemes against several attacks such as JPEG lossy compression, noise adding, sharpening, and blurring.
A copyright protection scheme based on chaos and secret sharing techniques is proposed. Instead of modifying the original image to embed a watermark in it, the proposed scheme extracts a feature from the image first. Then, the extracted feature and the watermark are scrambled by a chaos technique. Finally, the secret sharing technique is used to construct a shadow image. The watermark can be retrieved by performing an XOR operation between the shadow images. The proposed scheme has the following advantages. Firstly, the watermark retrieval does not need the original image. Secondly, the scheme does not need to modify the original image for embedding the watermark. Thirdly, compared with several schemes, the scheme is secure and robust in resisting various attacks.