Thomson Licensing

Nextamp Sa

Séverine Baudry

Philippe Nguyen

Bertrand Chupeau

Antoine Robert

Frederic Lefebvre

Gwenael Doerr

Frédéric Lefebvre

Cesar Burini

Javier Franco-Contreras

Noémie Lechable

Corinne Naturel

Philippe Roudot

Selective data encryption of a file, in particular an H.264/MPEG-4 AVC data stream. If a first unit in the data stream is to be encrypted, it is encrypted and the encryption is put into a further unit, preferably in the data stream. A substitution unit is generated and put in the place of the first unit; if necessary, at least one header value is taken from the first unit for use in the substitution unit. A decryptor receives the encrypted data stream, extracts and decrypts the further unit and replaces the substitution unit with a regenerated first unit.

Methods and devices for selective format-preserving data encryption

The invention relates to a method for assessing the presence of a watermark in a video wherein the video comprises at least a sequence of frames. The method comprises for at least one frame among one of the sequences of frames the steps of computing a set of axial cross-correlation values, wherein each axial cross-correlation value corresponds to a correlation between the frame and a reference watermark shifted along a spatial horizontal axis; obtaining a detection score by computing a weighted sum of values output by a function applied to said axial cross-correlation values; assessing the presence of a watermark according to the detection score. Such method is particularly well adapted to the detection of disparity coherent watermark but is compliant with any watermarking technique. A device implementing the method is further disclosed.

Method and device for assessing the presence of a watermark in a video

The invention relates to a method for decoding a watermark embedded in a video comprising blocks of samples representative of the video comprising the steps of determining in the video a location of a watermarked block; determining a location for each reference block among a plurality of reference blocks wherein a reference block is associated to a watermark value among a plurality of watermark values; comparing the watermarked block with each reference block; and identifying watermark value for the watermarked block from the results of the plurality of comparison. The method is remarkable in that each reference block is equally located in the video, for instance the pirated video, so that the plurality of comparisons between the watermarked block and each reference block is performed among the same video.

Method for watermark detection using reference blocks comparison

The invention relates to a method for temporal video registration of a target video with a master video comprising steps of automatic selection a plurality of key frames for target video and a plurality of key frames for master video; sparse registration of a plurality of key frames for target video with a plurality of key frames for master video; dense registration of frames of target video with frames of master video belonging to a temporal segment including registered key frames.

Method for two-step temporal video registration

The invention relates to a method for watermark embedding in multi views video comprising a plurality of views captured with a plurality of cameras comprising for each view a step of projecting the view onto a domain invariant to the plurality of views and to intermediate synthesized view, which depends on the locations, orientations, and intrinsic parameters of the cameras, resulting into an invariant vector; a step of applying a watermarking algorithm to the invariant vector resulting into a watermarked invariant vector; and a step of modifying the view to obtain a watermarked view, wherein said watermarked view when projected onto the invariant domain results into the watermarked invariant vector. The invention also relates to a method for watermark detection in a rendered view comprising a step of projecting the rendered view onto an invariant domain to the plurality of views resulting into an invariant rendered vector; a step of applying a watermark detection algorithm to the invariant rendered vector in order to assess the presence of a watermark.

Method for watermarking free view video with blind watermark detection

A method for temporal registration of a first sequence of images and a second sequence of second images is described. The method comprises the following steps for:

Signature based registration method and method for signature calculation

The invention relates to a method of watermarking a binary stream resulting from the encoding of a set of coefficients comprising at least one coefficient encoded by predictive coding, called predictively coded coefficient. The method comprises the steps of:

Digital watermarking method

The invention relates to a method for watermarking at least one timestamp in a set of support data, comprising the following steps for each timestamp: association with the timestamp of the value at a given time of a reference timestamp signal, that is a determinist signal varying over time in a given temporal reference and being written as s(t), wherein t is incremented according to an incrementing step equal to one predetermined time unit; and watermarking of the value in the set of support data. The invention also relates to a corresponding decoding method comprising the following steps: reading, in the set of support data, of at least one value of a phase-shifted timestamp signal, of the same form as the reference timestamp signal but having in relation to this signal an unknown phase shift &#x3c6; in a given temporal reference, the previous watermarking of each timestamp consisting in a watermarking of the value at a given watermarking time of the reference timestamp signal; estimation of the phase shift &#x3c6; from the at least one read value of the phase-shifted timestamp signal and from the knowledge of the reference timestamp signal; and for the at least one read value, read at a given time t, determination of an associated timestamp h associated according to the read time tand the estimated phase shift &#x3c6;.

Method for time-stamped watermarking, method and device for time stamp decoding use

The invention relates to a method of watermarking a data set comprising the steps of:

Method for watermarking a digital data set and device implementing said method

The invention relates to a method of reading a watermark, of the type comprising a step of determining at least one watermarking message contained in a data set, possibly preceded by a step of determining at least one suite of parameters of a watermarking channel undergone by the data set, each suite of channel parameters comprising at least one channel parameter. The step of determining at least one watermarking message and/or the prior step of determining at least one suite of channel parameters comprises (comprise): an estimation phase, consisting in processing at least one batch of data comprising data of the data set, so as to obtain N estimated element(s), with N&#x2267;0; and a verification phase, consisting in validating or invalidating, in view of the entirety or of at least a subset of the data set, each estimated element. In the foregoing, each estimated element is an estimated watermarking message, in the case of the step of determining at least one watermarking message, and a suite of estimated-channel parameters, in the case of the prior step of determining at least one suite of channel parameters.

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Rennes, France

Séverine Baudry