Abstract: The invention relates to a system for embedding a watermark into an input media signal. A plurality of sub-band signals of a sub-band encoded input signal is obtained; preferably by de-multiplexing of the corresponding bitstream. A set of sub-band signals is filtered by a sub-band filter (507) which has a response associated with the watermark. The sub-band filter (507) thereby generates a set of filtered sub-band signals which are combined into an output signal having the desired watermark. The output signal is preferably a compressed sub-band bitstream signal. A low complexity approach for embedding a watermark into a media signal by filtering in the sub-band domain is thus achieved obviating the requirement for decoding and re-encoding of the media signal.

Abstract: The invention relates to a system for re-encoding bitstreams for content signals. A re-encoder (101) receives a bit-stream comprising e.g. an MPEG-2 encoded signal. The receiver (109) feeds the bitstream to an extraction processor (111) which extracts non-essential information from the bitstream thereby generating a reduced bitstream which is still MPEG-2 compliant. The non-essential information, which specifically may be higher frequency transform coefficients, is re-encoded in a re-encode processor (113) using a non-MPEG-2 encoding principle. The encoding may be optimised for the characteristics of the non-essential information resulting in a more efficient encoding. The re-encoded data is inserted in user data section of the reduced bit stream by a combine processor (115). Thus, an effective reduction in the size of the bitstream may be achieved.

Abstract: The present invention relates to a methods, devices, a media signal as well as an information storage medium related to embedding additional data in a media signal. A first adding unit (12) mixes the media signal (x) with a noise signal (n) in order to provide a modified media signal (x+n), and a combiner unit (14) combines additional data (w) with the modified media signal (x+n) through multiplying the modified media signal with the additional data in order to provide a host modifying media signal (mw). In this way the additional data can be detected with a higher certainty in an output signal (y) if the media signal (x) includes few frequency components.

Abstract: A watermark detection method is disclosed which is based on computing the cross-correlation between a suspect signal and a watermark. In order to be more robust against prolonged dominant signal components that adversely affect the correlation, the sequence of signal samples (61) to be correlated with the watermark is divided into sub-sequences (A(k)). The sub-sequences are processed, by a weighting function, to obtain modified sub-sequences (B(k)) that individually exhibit the original signal variations, but collectively (62) exhibit a flatter distribution of sample values. Dominant peaks in the signal are thereby substantially reduced.

Abstract: The invention relates to methods, devices and a signal, where an encoder compresses a first piece of information in the form of at least a first limited part of an image, provides perceptible additional information (38) related to the image, and provides the compressed first piece of information (40) in the image (36) and a decoder retrieves the image including the compressed first piece of information in the form of at least a first limited part of the image as well as the perceptible additional information, retrieves the perceptible additional information, and decompresses at least the compressed piece of information essentially without the losses for provision of at least one of image and perceptible additional information essentially without losses. The invention also relates to an image editor, a computer program product and a computer program element for processing additional information (38) such that the original image is restorable.

Abstract: The invention relates to an information carrier (101) intended to be put into a rotary motion, said information carrier (101) comprising: display means (102) designed to display image data, said display means (102) being spatially located by a spatial position, processing means (103) for periodically sending to said display means (102) image data having the same spatial position as said display means (102).

Abstract: Fingerprinting is a technique to identify multimedia signals by extracting robust perceptual features of the signal contents and searching the extracted features in a database where titles, artists, etc. are stored. Watermarking is a technique of embedding payload data in a signal in an unobtrusive manner. The invention combines both techniques. A fingerprint (M(i)) is extracted (1) from a host signal (x) and stored in a database (5). A watermark (w(i)) is embedded (2) in the host signal by modifying (21) the signal, such that the fingerprint (M?(i)) of the modified signal (x?) differs slightly from the original fingerprint. The difference is so small that the database considers them to be similar. At the receiver end, the fingerprint is extracted (3) from the watermarked signal and applied to the database, which responds by returning the original fingerprint of the signal.