Abstract: 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.

Abstract: The invention relates in particular to a stream-wise method of watermarking independent of the compression parameters used (for example type of the transform) so as to allow the reading of the watermarking inserted independently of the format of the data received. The watermarking method according to the invention consists in generating a contribution matrix in the transformation space, in projecting it into another domain and in watermarking the data in this domain on the basis of the projected matrix so as to allow a watermark reader operating in the transformed transformation space to read back the inserted watermarking in the transformation space. The contribution matrix representing the modifications induced on the coefficients in the transformation space by insertion of the watermarking cue in this same domain.

Abstract: 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: a) identifying, in the binary stream, a first binary word representing the predictively coded coefficient; b) computing a modified coefficient from the predictively coded coefficient on the basis of at least one watermarking bit; c) encoding the modified coefficient into a second binary word; and d) replacing in the binary stream the first binary word with the second binary word.

Abstract: 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?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.

Abstract: The invention relates to a digital data set watermarking method including the following steps: a. Generating, from at least one part of the digital data set, a first set of M n-uplets representative of the digital data set where n and M are integers, M?1 and n?1, b. Determining, in a predefined batch of K n-uplets, a set of M n-uplets, called second set, closest in the sense of predefined metrics to the first set where K is an integer and K?M, and c. Modifying at least one data item of the digital data set in such a way that the first set generated according to step a) from the modified data set is equal to the second set.

Abstract: In a device and a method for the determining local geometrical variations that have occurred in data, the data comprise a reference pattern X. The method comprises, for example, the following steps: modeling the local geometrical variations by means of an index variable J, said variable making it possible to place the samples of the distorted data in correspondence with those of the original data, estimating the local variations by using the reference pattern X included, a model of local distortion of the data and the distorted data.

Abstract: A process for watermarking images that includes embedding into the images before their transmission a message by modifying the data characteristic of the images. Further, a co-watermarking is performed by periodic embedding of a binary matrix into the image to determine on reception the co-ordinates of the origin of the initial image and allow the registration of the images received relative to this origin so as to make it possible to read the embedded message. Such a process may find particular application to the transmission of stationary or video images.

Abstract: In a device and a method for the determining local geometrical variations that have occurred in data, the data comprise a reference pattern X.