• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.2
• /
• pp.1020-1042
• /
• 2019

Reversible data hiding in encrypted images (RDHEI) provides some real-time cloud applications; i.e. the cloud, acting as a data-hider, automatically embeds timestamp in the encrypted image uploaded by a content owner. Many existing methods of RDHEI only satisfy user privacy in which the data-hider does not know the original image, but leaks owner privacy in which the receiver can obtains the original image by decryption and extraction. In the literature, the method of Zhang et al. is the one providing weak content-owner privacy in which the content-owner and data-hider have to share a data-hiding key. In this paper, we take care of the stronger notion, called strong content-owner privacy, and achieve it by presenting a new reversible data hiding in encrypted images. In the proposed method, image decryption and message extraction are separately controlled by different types of keys, and thus such functionalities are decoupled to solve the privacy problem. At the technique level, the original image is segmented along a Hilbert filling curve. To keep image privacy, segments are transformed into an encrypted image by using random permutation. The encrypted image does not reveal significant information about the original one. Data embedment can be realized by using pixel histogram-style hiding, since this property, can be preserved before or after encryption. The proposed method is a modular method to compile some specific reversible data hiding to those in encrypted image with content owner privacy. Finally, our experimental results show that the image quality is 50.85dB when the averaged payload is 0.12bpp.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.4 no.2
• /
• pp.57-66
• /
• 2008

There have been proposed various copyright protection protocols in network-based digital multimedia distribution framework. However, most of conventional copyright protection protocols are focused on the stability of copyright information embedding/extracting and the access control to data suitable for user's authority but overlooked the privacy of copyright owner and user in authentication process of copyright and access information. In this paper, we propose a solution that builds a privacy-preserving proof of copyright ownership of digital contents in conjunction with keyword search scheme. The appeal of our proposal is three-fold: (1) content providers maintain stable copyright ownership in the distribution of digital contents; (2) the proof process of digital contents ownership is very secure in the view of preserving privacy; (3) the proposed protocol is the copyright protection protocol added by indexing process but is balanced privacy and efficiency concerns for its practical use.

• Journal of Digital Contents Society
• /
• v.9 no.4
• /
• pp.697-705
• /
• 2008

The recent web technology has been developed by three mainsprings which include integration, virtualization, and socialization. The web technology provides the increment of the social networking ability. However it deepens the exposure of privacy about personal information as more complicating and difficult problems. Representatively, it is impossible to define and manage the specific relation, so the personal information and interest can be inferred from collecting and summarizing the contents. Also, there are some problems that it is hard to construct the information owner's own social network. Thus this paper proposes the RCBAC(Relationship-Content based Access Control) Model which applies both the concepts of Relationship and Content Semantic to the existing access control methods to protect the user's own digital contents in web 2.0 environment. This method prevents privacy such as personal inclination from being exposed and enables to define and manage the specific relation. By doing this the information owners can construct their social network. This social network can be applied and extended to web contents.

• ETRI Journal
• /
• v.42 no.3
• /
• pp.446-458
• /
• 2020

In this study, an efficient scheme for hiding data directly in partially encrypted versions of high efficiency video coding (HEVC) videos is proposed. The content owner uses stream cipher to selectively encrypt some HEVC-CABAC bin strings in a format-compliant manner. Then, the data hider embeds the secret message into the encrypted HEVC videos using the specific coefficient modification technique. Consequently, it can be used in third-party computing environments (more generally, cloud computing). For security and privacy purposes, service providers cannot access the visual content of the host video. As the coefficient is only slightly modified, the quality of the decrypted video is satisfactory. The encrypted and marked bitstreams meet the requirements of format compatibility, and have the same bit rate. At the receiving end, data extraction can be performed in the encrypted domain or decrypted domain that can be adapted to different application scenarios. Several standard video sequences with different resolutions and contents have been used for experimental evaluation.

• Journal of Community Nutrition
• /
• v.8 no.1
• /
• pp.9-15
• /
• 2006

Health care is one of the most popular reasons for accessing the Internet. Of concern is the amount of information from disreputable sources available on the Internet. A review of websites offering nutrition consulting services suggests sites are controlled by both registered dietitians and non-dietitian professionals marketing themselves as nutrition consultants. The purpose of this study was to investigate structure and content of websites controlled by registered dietitians and nondietitians professionals marketing themselves as nutritionists or nutrition consultants. Internet search queries of 'dietitian', 'dietitian consultant', and 'nutrition consultant' were completed for website selection. Thirty websites controlled by registered dietitians and 10 websites controlled by nutrition consultants were reviewed using an 18-item website evaluation instrument developed for this study. Five evaluators were recruited from the dietetics program at the University of Kentucky. Overall, websites controlled by registered dietitians ranked higher than websites controlled by nutrition consultants in a majority of categories. Sites controlled by registered dietitians ranked statistically higher for the following categories: 'accuracy of information'(p<.0001), 'inclusion of professional resume of owner or primary manager' (p<.05), and 'explanation of the affiliation to externallinks'(p<.05). A majority of sites controlled by both dietitians and nutrition consultants achieved a poor ranking in regards to provision of a legal disclaimer and inclusion of a privacy policy. Prior studies suggest personal privacy is the most important concern for consumers accessing health information on the Internet. Findings from this project will benefit dietitians to assist in development of reputable nutrition related websites.