Now showing 1 - 10 of 37
  • Publication
    Digital signatures based on invertible watermarks for video authentication
    ( 2005)
    Hauer, E.
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    Dittmann, J.
    ;
    Steinebach, M.
  • Publication
    Design principles for active audio and video fingerprinting
    ( 2005)
    Steinebach, M.
    ;
    Dittmann, J.
  • Publication
    Advanced audio watermarking benchmarking
    ( 2004)
    Dittmann, J.
    ;
    Steinebach, M.
    ;
    Lang, A.
    ;
    Zmudizinski, S.
    Digital watermarking is envisaged as a potential technology for copyright protection and manipulation recognition. A key issue in the usage of robust watermarking is the evaluation of robustness and security. StirMark Benchmarking has been taken to set a benchmarking suite for audio watermarking in addition to existing still image evaluation solutions. In particular we give an overview of recent advancements and actual questions in robustness and transparency evaluations, in complexity and performance issues, in security and capacity questions. Further more we introduce benchmarking for content-fragile watermarking by summarizing design aspects and concluding essential benchmarking requirements.
  • Publication
    A high-capacity block based video watermark
    ( 2004)
    Thiemert, S.
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    Vogel, T.
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    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
    Capacity-optimized mp2 audio watermarking
    ( 2003)
    Steinebach, M.
    ;
    Dittmann, J.
    Today a number of audio watermarking algorithms have been proposed, some of them at a quality making them suitable for commercial applications. The focus of most of these algorithms is copyright protection. Therefore, transparency and robustness are the most discussed and optimised parameters. But other applications for audio watermarking can also be identified stressing other parameters like complexity or payload. In our paper, we introduce a new mp2 audio watermarking algorithm optimised for high payload. Our algorithm uses the scale factors of an mp2 file for watermark embedding. They are grouped and masked based on a pseudo-random pattern generated from a secret key. In each group, we embed one bit. Depending on the bit to embed, we change the scale factors by adding 1 where necessary until it includes either more even or uneven scale factors. An uneven group has a 1 embedded, an even group a 0. The same rule is later applied to detect the watermark. The group size can be increased or decreased for transparency/payload trade-off. We embed 160 bits or more in an mp2 file per second without reducing perceived quality. As an application example, we introduce a prototypic Karaoke system displaying song lyrics embedded as a watermark.
  • 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
    Digitale Wasserzeichen - Grundlagen - Anwendungen - Grenzen
    ( 2002)
    Steinebach, M.
    ;
    Dittmann, J.
    Digital watermarking has become an often-discussed approach for digital rights management (DRM). Owner authentication, identification of pirates and even prevention of illegal copies are addressed. We provide an overview of watermarking technology. Furthermore we identify problems in watermarking-based DRM and show application scenarios: H2O/sub 4/M provides a combined security approach including PKI and biometrics. Transmark is a DRM example for media on demand. We discuss new methods of advertisement and content-protection for digital media.