Protecting Metadata of Access Indicator and Region of Interests for Image Files With popularity of social network services, the security and privacy issues over shared contents receive many attentions. Besides, multimedia files have additional concerns of copyright violation or illegal usage to share over communication networks. For image file management, JPEG group develops new image file format to enhance security and privacy features. Adopting a box structure with different application markers, new standards for privacy and security provide a concept of replacement substituting a private part of the original image or metadata with an alternative public data. In this paper, we extend data protection features of new JPEG formats to remote access control as a metadata. By keeping location information of access control data as a metadata in image files, the image owner can allow or deny otherxe2x80x99s data consumption regardless where the media file is. License issue also can be resolved by applying new access control schemes, and we present how new formats protect commercial image files against unauthorized accesses.

Blind Multipurpose Image Watermarking Based on Secret Sharing In this paper, in order to accomplish two goals of multimedia authentication and copyright protection, we present a multipurpose watermarking method based on a commonly used cryptographic primitive called verifiable secret sharing scheme. Utilizing this primitive, our scheme achieves blindness meaning that it needs neither the original host image nor the embedded watermark. Our scheme also does not need two distinct watermarks to authenticate the images and at the same time protect their copyright. Experimental results show that the features of the shares, obtained by the used primitive from watermark, enables our method to reconstruct extracted tampered watermarks after various attacks such as JPEG compression, cropping, salt and pepper noise, median filtering, some combined attacks, etc. Comparisons are provided with other multipurpose watermarking methods which primarily aim at protecting copyright of media and authenticating it simultaneously. We also show the superiority of our proposed method to three watermarking methods attaining the goals of copyright protection and authentication.