Canon Kabushiki Kaisha

Ioana Donescu

Fabrice Le Leannec

Eric Nassor

Eric Nguyen

Patrice Onno

Pascal Viger

Frédéric Maze

Hervé Le Floch

Eric Majani

Frédérique Ehrmann Patin

This method of transmission of an animation in a digital image by a first server containing a descriptive file of the animation to a client, an animation being defined by a series of portions of a digital image according to a plurality of requests to be received from the client, comprises the steps of, at reception by the first server of a request from the client on the animation descriptive file, transmission () of the descriptive file to the client and to a second server. The second server is enabled to prepare () appropriate responses to a series of client requests deduced from the descriptive file and anticipating the plurality of requests to be received from the client.

Method and device for pre-processing requests related to a digital signal in an architecture of client-server type

The invention relates to a method of processing digital data constituting a signal in a distributed communication network comprising a plurality of communication apparatuses, the signal being identified by a unique identifier (ID), characterized in that the method comprises the following steps:

Method and device for processing digital data with a unique identifier

A method of allocating at least one service by a first peer (E) to a second peer (D), the peers being linked by means of a computer communication network, the first and second peers belonging respectively to a first and second group of peers adapted to share data, comprises the following steps:

Method of allocating a service by a first peer to a second peer in a communication network

The invention concerns a method of inserting a suppementary information item in a set of data reprenting physical quantities, the data having been processed by the steps of, a) partitioning (E) the set into subsets, b) entropic coding (E) of each of the subsets, c) selecting (E), for each of the subsets, a compression rate and distortion pair according to a global compression rate or a global distortion, d) writing, for each of the subsets, an index (T) representing the selected compression rate and distortion pair, in a file containing the coded subsets, characterised in that it also includes a step (E) of modifying the selected compression rate and distortion pairs, according to the supplementary information (w).

Insertion of supplementary information in digital data

The invention relates to a method of processing a digital signal identified by a unique identifier in a distributed communication network composed of several communication apparatuses, comprising the steps of:

Method and device for data processing in a communication network

In a method of controlling a document sharing support apparatus, there is received information representing the fact that a first computer is storing at least a low-resolution version of a document, and the low-resolution version of the document is acquired and stored. There is received a request for obtaining the document from a second computer, and the low-resolution version of the document in memory is made available to the second computer.

Method of distributing multiresolution digital documents

The invention concerns a method of inserting a message in an image, characterized in that it comprises the steps of:

Insertion and extraction of a message in an image

The invention proposes a method of inserting a message in a subset (VO) of digital data representing physical quantities, characterized in that it includes the steps of: The invention applies particularly to an object in a digital image.

Insertion of messages in digital data

A method for the prior monitoring of the detectability of a watermarking signal inserted by modulation in a set of coefficients representing for example a digital image. The method comprises the step of simulating a distortion on the set of modulated coefficients, the distortion corresponding to a given compression level of the set of coefficients before modulation, determined by optimisation of a ratio of transmission rate to distortion. The method further comprises the step of calculating a detectability test on the set of modulated coefficients after distortion, and a step of comparing the detectability test with a threshold detection value. The method is used notably for inserting a watermarking signal during the compression of a digital image.

Method for the prior monitoring of the detectability of a watermarking signal

A method of determining a partition into distinct regions of a set of coefficients representative of at least a part of an image in order to insert a watermark comprises the following steps: Use especially for determining an adaptative partition as a function of a criterion of detectability of an information bit inserted on each region.

Method for determining a partition in order to insert a watermark, and associated insertion and decoding methods

In order to decode a received digital signal which has been watermarked with a known watermark, at least part of the digital signal is decoded by using a parametrisable iterative decoder, the watermark is extracted from the decoded signal, the extracted watermark is compared with the known watermark, and at least one parameter of the decoder is modified if necessary, according to the result of the comparison.

Method and device for sending and receiving digital images using an image watermark for decoding

The invention concerns a method of processing a set of coefficients representing a digital image () with a view to an insertion of at least one item of watermarking information in said image, this image being liable to undergo a set of geometric transformations and said coefficients being grouped together in regions, said method being characterized in that it includes a step (E) of determining, amongst at least some of said regions, a set of so-called acceptable regions, adapted to receive said at least one item of watermarking information; and a step (E) of sequencing, according to at least one predetermined criterion, at least one part of said set of acceptable regions, in an order which is invariant with respect to at least one of said geometric transformations.

Method and device for processing and watermarking a set of coefficients representing a digital image

A method of inserting a watermark in digital data (I) includes the steps of multi-resolution spectral breakdown (E) of the digital data (I); extraction (E) of the components of lowest frequency; choice (E) of a subset of the components with the lowest frequency; modulation (E) of the components of said subset in order to insert the supplementary information (S); and reverse multi-resolution spectral recomposition (E) of the watermarked digital data (I').

Method and device for inserting and decoding a watermark in digital data

A method of inserting a watermarking signal (w) in a set (X) of coefficients (X ) representing a digital image (I), in which at least one subset of coefficients is modified by said watermarking signal (w), comprises, for each representative coefficient (X ) to be modified, a step of determining a neighborhood (V(X )) of the representative coefficient (X ) to be modified, in the image (I); a step of selecting a neighborhood (V ) in a dictionary of neighborhoods representing coefficients representing the image (I), according to a predetermined criterion of similarity with the neighborhood (V(X )) of the representative coefficient (X ) under consideration; and a step of modifying the representative coefficient (X ) as a function of the watermarking signal (w) and a predetermined masking data item (M(V )) representing the masking effect on a watermarking signal, of the neighborhood (V ) selected in the dictionary.

Method and device for inserting a watermarking signal in an image

The invention concerns a method of inserting an additional information item in a set of digital data representing physical quantities, the data having been processed by transformation, quantization and entropic coding in order to be compressed, characterized in that it comprises the steps of extracting a subset of low-frequency coefficients, from the set of data, entropic decoding of the coefficients of the subset, modulation of the decoded coefficients by a signal representing the additional information item, so as to form quantized watermarked coefficients, entropic coding of the watermarked coefficients, and insertion of the watermarked encoded coefficients in place of the coefficients of the subset, in the set of data.

Growing community of inventors

Rennes, France

Ioana Donescu