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Fragile watermarking using finite field trigonometrical transforms / R. J. Cintra in Signal processing. Image communication, Vol. 24 N° 7 (Août 2009) 

Public ISBD [article]  in Signal processing. Image communication > Vol. 24 N° 7 (Août 2009) . - pp. 587-597 Titre : Fragile watermarking using finite field trigonometrical transforms Type de document : texte imprimé Auteurs : R. J. Cintra, Auteur ; V.S. Dimitrov, Auteur ; H.M. de Oliveira, Auteur Article en page(s) : pp. 587-597 Note générale : Electronique Langues : Anglais (eng) Mots-clés : Fragile  watermarking  Number  theoretic  transforms  Finite  field  trigonometry Index. décimale : 621.382 Dispositifs électroniques utilisant les effets des corps solides. Dispositifs semi-conducteurs Résumé : Fragile digital watermarking has been applied for authentication and alteration detection in images. Utilizing the cosine and Hartley transforms over finite fields, a new transform domain fragile watermarking scheme is introduced. A watermark is embedded into a host image via a blockwise application of two-dimensional finite field cosine or Hartley transforms. Additionally, the considered finite field transforms are adjusted to be number theoretic transforms, appropriate for error-free calculation. The employed technique can provide invisible fragile watermarking for authentication systems with tamper location capability. It is shown that the choice of the finite field characteristic is pivotal to obtain perceptually invisible watermarked images. It is also shown that the generated watermarked images can be used as publicly available signature data for authentication purposes. DEWEY : 361.382 ISSN : 0923-5965 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235640%23 [...] [article] Fragile watermarking using finite field trigonometrical transforms [texte imprimé] / R. J. Cintra, Auteur ; V.S. Dimitrov, Auteur ; H.M. de Oliveira, Auteur . - pp. 587-597. Electronique Langues : Anglais (eng) in Signal processing. Image communication > Vol. 24 N° 7 (Août 2009) . - pp. 587-597 Mots-clés : Fragile  watermarking  Number  theoretic  transforms  Finite  field  trigonometry Index. décimale : 621.382 Dispositifs électroniques utilisant les effets des corps solides. Dispositifs semi-conducteurs Résumé : Fragile digital watermarking has been applied for authentication and alteration detection in images. Utilizing the cosine and Hartley transforms over finite fields, a new transform domain fragile watermarking scheme is introduced. A watermark is embedded into a host image via a blockwise application of two-dimensional finite field cosine or Hartley transforms. Additionally, the considered finite field transforms are adjusted to be number theoretic transforms, appropriate for error-free calculation. The employed technique can provide invisible fragile watermarking for authentication systems with tamper location capability. It is shown that the choice of the finite field characteristic is pivotal to obtain perceptually invisible watermarked images. It is also shown that the generated watermarked images can be used as publicly available signature data for authentication purposes. DEWEY : 361.382 ISSN : 0923-5965 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235640%23 [...]