Fault-tolerant VQ-style Secret Image Sharing

Abstract

In this paper, we propose a fault-tolerant secret image sharing scheme based on vector quantization (VQ). The proposed method uses some of the n host images to generate the codebooks for VQ, and compresses the secret image by VQ with the generated codebooks. The VQ indices are thus created and then shared among n shadows. After obtaining the n shadows, they are embedded together with the mixed information of the generated codebooks into the n host images to form the n stego-images. When collecting any r (r <= n) of the n stego-images, the VQ indices and codebooks can be retrieved to recover the secret image. However, no information about the secret image can be revealed if obtaining less than r stego-images. Because of using VQ, the secret image is compressed to the VQ indices, and thus easier to be hidden than the non-compressed one. The quality of the recovered image is the same as the one of the ordinary VQ.