Despite the success of watermarking technique for protecting depth image-based rendering (DIBR) 3-D videos, existing methods still can hardly ensure the robustness against geometric attacks, lossless video quality, and distinguishability between different videos simultaneously. In this article, we propose a novel zero-watermarking scheme to address this challenge. Specifically, we design CT-SVD features to ensure both distinguishability and robustness against signal processing and DIBR conversion attacks. In addition, a logistic–logistic chaotic system is utilized to encrypt features for the enhanced security. Moreover, a rectification mechanism based on salient map detection and SIFT matching is designed to resist geometric attacks. Finally, we establish an attention-based fusion mechanism to explore the complementary robustness of rectified and unrectified features. Experimental results demonstrate that our proposed method outperforms the existing schemes in terms of losslessness, distinguishability, and robustness against geometric attacks.

Zero-watermarking is a key technique for achieving lossless and flexible copyright protection of depth image-based rendering (DIBR) videos. Existing approaches extract features of both 2D frames and depth maps via a single mechanism to protect them simultaneously. However, it is difficult for these schemes to fully satisfy the copyright protection requirements of the two components, including the remarkable discriminative capability of 3D videos and robustness against various attacks. Hence, in this paper, we propose a novel multiple-feature-based zero-watermarking scheme to protect the copyright of DIBR 3D videos. To the best of our knowledge, this is the first scheme that integrates multiple features to improve both the discriminative capability and robustness against various attacks. Specifically, dual-tree complex wavelet transform and discrete cosine transform features enhance the robustness against DIBR conversion and noise addition, respectively, while ring-partition statistical residual features ensure robustness against geometric attacks and provide sufficient discriminative capacity. In addition, we use a logistic-logistic chaotic system to encrypt these multiple features for enhanced security and design an attention based fusion approach to offer an optimal copyright protection solution. Extensive experimental results demonstrate that our proposed scheme has stronger robustness and discriminative capacity compared to state-of-the-art zero-watermarking methods. (C) 2022 The Author(s). Published by Elsevier Inc.

In recent years, coverless image steganography attracts significant attentions due to its distortion-free trait on carrier images to avoid the detection by steganalysis tools. Despite this advantage, current coverless methods face several challenges, e.g., vulnerability to geometrical attacks and low hidden capacity. In this paper, we propose a novel coverless steganography algorithm based on chaotic encrypted dual radial harmonic Fourier moments (DRHFM) to tackle the challenges. In specific, we build mappings between the extracted DRHFM features and secret messages. These features are robust to various of attacks, especially to geometrical attacks. We further deploy the DRHFM parameters to adjust the feature length, thus ensuring the high hidden capacity. Moreover, we introduce a chaos encryption algorithm to enhance the security of the mapping features. The experimental results demonstrate that our proposed scheme outperforms the state-of-the-art coverless steganography based on image mapping in terms of robustness and hidden capacity.

The authenticity and copyright protection of volumetric medical images has become extremely important when these images are distributed online for diagnosis and education purpose. Compared to the authenticity and copyright protection of conventional images, there are two additional challenges for protecting the volumetric medical images. On one hand, the content of the protected medical images must be distortion-free to ensure unbiased diagnosis. On the other hand, it requires enhanced distinguishability to avoid misclassification of non-protected images into the protected set because volumetric medical images of different persons in the same modality share similar visual structures. To address these issues, a novel multi-slice feature based zero-watermarking scheme with enhanced distinguishability and robustness for volumetric medical imaging is proposed. In this scheme, ring statistics are deployed to guarantee both the watermarking distinguishability and robustness. In addition, an intra-slice variation based mechanism is designed to further enhance the watermarking distinguishability. Finally, a logistic-logistic system based chaotic map is used to ensure the watermarking security. Our experimental results demonstrate that the proposed scheme not only satisfies the lossless quality requirement but also ensures the watermarking distinguishability and robustness, which outperforms the state-of-the-art schemes.

Copyright protection of depth image-based rendering (DIBR) 3D videos is crucial due to the popularity of these videos. Despite the success of recent watermarking schemes, it is still challenging to ensure the robustness against strong geometric attacks when both lossless quality and distinguishability of protected videos are required. In this paper, we pro-pose a novel zero-watermarking scheme to improve the performance under strong geometric attacks when satisfying the other two requirements. In our scheme, CT-SVD-based features are extracted to ensure both distinguishability and robustness against signal processing and DIBR conversion at-tacks, while a SIFT-based rectication mechanism is designed to resist geometric attacks. Further, an attention-based fusion strategy is proposed to complement the robustness of rectied and unrectied CT-SVD features. Experimental results demonstrate that our scheme outperforms the existing zero-watermarking schemes in terms of distinguishability and robustness against strong geometric attacks such as rotation, cyclic translation and shearing.