A high-capacity distortion-free information hiding algorithm for 3D polygon models

A high-capacity distortion-free information hiding algorithm for 3D polygon models is presented. We introduce a novel embedding approach called representation permutation to embed messages in the representation domain. The proposed approach embeds messages by permuting/rearranging vertex representation orders, triangle representation orders, and connectivity information. In contrast to the general data hiding schemes that embed messages by slightly modifying the appearance of cover media, the proposed approach will not degrade any perceptual quality of the cover model, that is, without visual distortion. In addition, the proposed approach can hide (∂_p +β_p) n_v bits on a polygon model (n_v represents the number of vertices, and the variables ∂_p and β_p are greater than 2.1 and 3.7, respectively). Furthermore, the proposed approach can easily combine with other spatial-based and spectral-based information hiding schemes to provide additional hiding capacity. Experimental results show that the proposed approach is efficient and can provide greater hiding capacity than recent techniques, while complying with the basic security requirement for steganography.