Now showing 1 - 10 of 62
  • Publication
    Digital signatures based on invertible watermarks for video authentication
    ( 2005)
    Hauer, E.
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    Dittmann, J.
    ;
    Steinebach, M.
  • Publication
    Secure production of digital media
    ( 2005)
    Steinebach, M.C.
    ;
    Dittmann, J.
    Today more and more media data is produced completely in the digital domain without the need of analogue input. This brings an increase of flexibility and efficiency in media handling, as distributed access, duplication and modification are possible without the need to move or touch physical data carriers. But this also reduces the security of the process: Without physical originals to refer to, changes in the material can remain unnoticed, at the end making the manipulated data the new original. Theft and illegal copies in the digital domain can happen without notice and loss of quality. We therefore see the need of setting up secure media production environments, where access control, integrity and copyright protection as well as traceability of individual copies are enabled. Addressing this need, we design a framework for media production environments, where mechanisms like encryption, digital signatures and digital watermarking help to enable a flexible yet secure handling and processing of the content.
  • Publication
    Design principles for active audio and video fingerprinting
    ( 2005)
    Steinebach, M.
    ;
    Dittmann, J.
  • Publication
    A high-capacity block based video watermark
    ( 2004)
    Thiemert, S.
    ;
    Vogel, T.
    ;
    Dittmann, J.
    ;
    Steinebach, M.
  • Publication
    Watermarking-based digital audio data authentication
    ( 2003)
    Steinebach, M.
    ;
    Dittmann, J.
    Digital watermarking has become an accepted technology for enabling multimedia protection schemes. While most efforts concentrate on user authentication, recently interest in data authentication to ensure data integrity has been increasing. Existing concepts address mainly image data. Depending on the necessary security level and the sensitivity to detect changes in the media, we differentiate between fragile, semifragile, and content-fragile watermarking approaches for media authentication. Furthermore, invertible watermarking schemes exist while each bit change can be recognized by the watermark, which can be extracted and the original data can be reproduced for high-security applications. Later approaches can be extended with cryptographic approaches like digital signatures. As we see from the literature, only few audio approaches exist and the audio domain requires additional strategies for time flow protection and resynchronization. To allow different security levels, we have to identify relevant audio features that can be used to determine content manipulations. Furthermore, in the field of invertible schemes, there are a bunch of publications for image and video data but no approaches for digital audio to ensure data authentication for high-security applications. In this paper, we introduce and evaluate two watermarking algorithms for digital audio data, addressing content integrity protection. In our first approach, we discuss possible features for a content-fragile watermarking scheme to allow several postproduction modifications. The second approach is designed for high-security applications to detect each bit change and reconstruct the original audio by introducing an invertible audio watermarking concept. Based on the invertible audio scheme, we combine digital signature schemes and digital watermarking to provide a public verifiable data authentication and a reproduction of the original, protected with a secret key.
  • Publication
    Digitale Audiowasserzeichen im Archivbereich - Das H2O4M Projekt
    ( 2003)
    Steinebach, M.
    ;
    Hauer, E.
    ;
    Dittmann, J.
  • Publication
  • Publication
    Watermarking protocols for authentication and ownership protection based on timestamps and holograms
    ( 2002)
    Dittmann, J.
    ;
    Steinebach, M.
    ;
    Ferri, L.C.
    Digital watermarking has become an accepted technology for enabling multimedia protection schemes. One problem here is the security of these schemes. Without a suitable framework, watermarks can be replaced and manipulated. We discuss different protocols providing security against rightful ownership attacks and other fraud attempts. We compare the characteristics of existing protocols for different media like direct embedding or seed based and required attributes of the watermarking technology like robustness or payload. We introduce two new media independent protocol schemes for rightful ownership authentication. With the first scheme we ensure security of digital watermarks used for ownership protection with a combination of two watermarks: first watermark of the copyright holder and a second watermark from a Trusted Third Party (TTP). It is based on hologram embedding and the watermark consists of e.g. a company logo. As an example we use digital images and specify the properties of the embedded additional security information. We identify components necessary for the security protocol like timestamp, PKI and cryptographic algorithms. The second scheme is used for authentication. It is designed for invertible watermarking applications which require high data integrity. We combine digital signature schemes and digital watermarking to provide a public verifiable integrity. The original data can only be reproduced with a secret key.
  • Publication
  • Publication
    Combined fingerprinting attacks against digital audio watermarking: Methods, results and solutions
    ( 2002)
    Steinebach, M.
    ;
    Dittmann, J.
    ;
    Saar, E.
    The methods for secure customer identification by digital fingerprinting for audio data are discussed. The algorithms by D. Boneh et al. (Proc. CRYPTO'95, p.452-465, 1995) and Joerg Schwenk et al. (Proceedings of SPIE, vol. 3657, p.24-29, Jan. 1999) are discussed and are then combined with an audio watermarking algorithm for practical evaluation of their coalition resistance to detect illegal copies. Test results are provided and the security performance against different types of coalition attacks is evaluated.