Abstract:
L'invention vise un procédé d'augmentation de la sensibilité d'un détecteur de filigrane. Le procédé est relatif à l'extraction d'un filigrane composé par la répétition des composantes élémentaires de la charge à transmettre dans un canal de couverture. Le procédé comprend : - une étape d'extraction de composantes élémentaires répétées; puis - une étape d'évaluation de la qualité individuelle (par exemple la fiabilité) de chaque répétition de chaque composante élémentaire; - une étape de sélection des individualités formant la répétition de chaque composante élémentaire; - une étape de fusion des lauréats de la sélection précédente pour déterminer la valeur de chaque composante élémentaire constituant l'information filigranée au signal de couverture.
Abstract:
A method of embedding a watermark in video data includes generating a watermark to be embedded in the video data, generating a bit string based on a generated watermark, and embedding a watermark in the video data by changing a quantization parameter of the video data by a predetermined value based on the bit string.
Abstract:
Various implementations are provided for, for example, determining watermarking data, performing the watermarking, and processing watermarked data. At least one implementation watermarks AVC bitstream that uses CAVLC entropy coding. The watermarking data may be determined in a pre-processing stage and stored for later use in watermark a bitstream. One method accesses (810) variable-length encoded data including an encoding of information identifying an actual reference used to predictively encode an image. The encoding of the information has a particular value. The method determines (830) an alternative value that is different from the particular value, such that the alternative value is an encoding of alternative information that identifies a different reference from the actual reference. The alternative value is for use in watermarking the variable-length encoded data.
Abstract:
The invention relates to a method of detecting the watermarking of a digital signal (S') that has been watermarked with the application of a watermarking function to pre-determined attributes of the signal. The inventive method comprises the application of a watermarking key extraction function in order to: select (50) the watermarked attributes and to locate the co-ordinates thereof in a reference partition comprising as many zones (Z
Abstract:
Disclosed is a method of embedding both a robust and a fragile watermark in an information signal which is compressed so as to include first signal samples having a first given value and further signal samples having a different value, wherein embedding the robust watermark. The method comprises the steps of: modifying signal samples in accordance with a watermark pattern if the act of modifying results in the modified signal sample assuming the first value; and wherein embedding the fragile watermark comprises the steps of: counting the number of ‘ones’ remaining (R) in the signal as a result of embedding the robust watermark; counting the number of ‘ones’ discarded (D) from the signal as a result of embedding the robust watermark; and determining a fragile payload on the basis of said remaining ( R ) and discarded (D) ‘ones’.
Abstract:
A method and arrangement are disclosed for processing a compressed media signal, for example, embedding a watermark in an MPEG2 video signal. The watermark, a spatial noise pattern (140), is embedded (123) by selectively discarding the smallest quantized DCT coefficients. The discarded coefficients are subsequently merged in the runs of other run/level pairs. To compensate for a too large reduction of the bit rate, some of the new run/level pairs are not variable-length encoded (124) but represented by longer code words according to further coding rule (125) providing such longer code words, for example, MPEG's "Escape coding".
Abstract:
A data processing device for burying additional information in coded data created by encoding image data and correctly reproducing the image data and the additional data from the coded data without increasing the amount of coded data. A burying compression-encoder (11) encodes image data according to a predetermined encoding rule and destroys the encoding rule according to the additional information so as to bury the additional information. A decoder (12) restores burying coded data generated by burying the additional information in the coded data to the coded data encoded according to the encoding rule, and thereby the additional information is decoded and the coded data is decoded to image data.
Abstract:
Method and system for embedding information and authenticating a H.264 video using a digital watermark. It comprises a watermarking and H.264 video stream generation module (100) for embedding a watermark in non-entropy-coded H.264 syntax elements (H.264 SE ), processing each frame j to pseudorandomly determine whether a given macroblock is a candidate macroblock for conveying the watermark and check whether a determined set of conditions to watermark a selected coefficient (COEFS) of a selected block (BLOCKS) of the candidate macroblock are met, which are met when the candidate macroblock is a 4×4 intra coded macroblock (I4x4) and the selected block of the candidate macroblock to convey the watermark belongs to a predefined set of candidate blocks and the intra prediction modes of its successive adjacent blocks do not take as input the value of the selected block. The module (100) then embed the watermark in the selected coefficient (COEFS) of the selected block (BLOCKS) meeting the set of conditions.
Abstract:
Die Erfindung betrifft ein Verfahren zum Markieren von zumindest einem ersten Abschnitt eines Datenstroms mit einem Wasserzeichen, wobei der Datenstrom zumindest einen ersten Abschnitt und zumindest einen zweiten Abschnitt umfasst, bei dem zumindest einer der ersten Abschnitte in dem Datenstrom als zu markierender Abschnitt aufgrund eines Auswahlkriteriums ausgewählt wird, wobei das Auswahlkriterium angibt, dass der zu markierende Abschnitt bei einer Verarbeitung anderer erster und zweiter Abschnitte unberücksichtigt bleibt, ein geschützter Abschnitt durch Markieren des zu markierenden Abschnitts mit dem Wasserzeichen generiert wird, durch Einfügen des geschützten Abschnitts an die Stelle des zu markierenden Abschnitts in den Datenstrom ein geschützter Datenstrom erzeugt wird. Die Erfindung umfasst auch ein Verfahren zum Erkennen von geschützten Abschnitten eines geschützten Datenstroms und ein Verfahren zum Entfernen von Wasserzeichen aus zumindest einem geschützten Abschnitt des geschützten Datenstroms. Ferner betrifft die Erfindung auch eine Markierungsvorrichtung zum Durchführen des Verfahrens zur Markierung, eine Erkennungsvorrichtung zum Durchführen des Verfahrens zum Erkennen und eine Entfernungsvorrichtung zum Durchführen des Verfahrens zum Entfernen.
Abstract:
A method and a system for modifying a bitstream signal for enabling collusion resistant bitstream watermarking. The method comprises dividing a bitstream spectral signal X[k] of the bitstream signal bx into a first signal (302) and a second signal (304); multiplying the first signal (302) by a first modification signal (306) and outputting a modified first signal (314); performing a transform operation on said second signal (304) for obtaining a transformed second signal (308); multiplying said transformed second signal (308) by a second modification signal (310) and outputting a second modified signal (312); subtracting said second modified signal (312) from said first modified signal (314) and outputting a modified bitstream spectral signal X'[k] suitable for obtaining a modified bitstream signal b'x of said bitstream signal bx. Thus an efficient manner of applying a collusion resistant property for already encoded contents is provided.