Abstract: A secure media storage device for an imaging device, comprising an interface (40) for receiving digital data, a memory (44) for storing the digital data and for allowing read out of the digital data and a security layer (42) integrated onto the storage device for embedding security data onto the digital data to enable verification of the integrity of the digital data.

Abstract: The invention provides a method and apparatus for watermarking a document, the method comprising: associating the document with an identification number; generating (70) a first set of numbers using a seed for the number generation comprising or derived from the identification number; applying a transform (62) to at least a portion of an image of the document to form a transform of the image; defining a second set of numbers comprising transform coefficients from the transform of the image; forming a modified second set of numbers based on the first set and the second set; substituting the modified second set for the second set in the transform of the image to form a modified transform (72); and applying an inverse (74) of the transform to the modified transform to thereby produce a modified image of the document; whereby the modified image of the document or an output of the modified image constitutes the watermarked document.

Abstract: The invention provides a method and apparatus for watermarking a document, the method comprising: associating the document with an identification number; generating (70) a first set of numbers using a seed for the number generation comprising or derived from the identification number; applying a transform (62) to at least a portion of an image of the document to form a transform of the image; defining a second set of numbers comprising transform coefficients from the transform of the image; forming a modified second set of numbers based on the first set and the second set; substituting the modified second set for the second set in the transform of the image to form a modified transform (72); and applying an inverse (74) of the transform to the modified transform to thereby produce a modified image of the document; whereby the modified image of the document or an output of the modified image constitutes the watermarked document.

Abstract: A method for embedding an entire image, audio or video watermark sequence within another image, audio or video data sequence with minimum loss of data quality is presented. The method exploits the de-correlation property of data coefficients in the orthogonal transform domain, similar to the application in data compression through transform coding. The present invention describes the usage of a Discrete Cosine Transform as the embedding domain. However, other orthogonal transforms such as Fourier, Walsh-Hadamard, Haar, Sine and Wavelet can also be used for this operation. A unique key derived adaptively from spatial locations registering the thresholds of the ac transform energies is used to unlock or de-watermark the embedded image or audio sequence. Moreover, an exponential filter has been developed to compress and expand the watermark coefficients prior to the embedding and retrieval process.