Abstract: A method for determining the amplitude of a movement performed by a member of an articulated body comprises: obtaining a segment representative of the positioning of the member in a given reference frame at the end of said movement, generating a three-dimensional model of the member, positioned in said reference frame by means of the obtained segment, obtaining a cloud of three-dimensional points representing the member in said reference frame at the end of said movement, based on depth information provided by a sensor, said depth information defining a three-dimensional scene comprising at least a part of the articulated body including said member, repositioning the model of the member so as to minimize a predetermined error criterion between the obtained cloud of points and said model, and determining the amplitude of the movement, based on the new positioning of the model of the member.

Abstract: A method is described for converting an input image into an output image, the output image including an output luminance component made of elements. The method includes: obtaining an input luminance component from the input image; determining the output luminance component, the respective ranges of the output luminance component element values and input luminance component element values being of different range extension, the determining step including: —determining a first intermediate luminance component from the input luminance component and an exponent, —obtaining a mapping profile allowing for mapping a luminance component based on the input luminance component into the output luminance component, —determining a second intermediate luminance component from the input luminance component and the obtained mapping profile, —determining the output luminance component from the first and second intermediate luminance components; and converting the input image into the output image.

Abstract: A method for decoding a digital image from encoded data representative of the image. The image is divided into blocks processed in a defined order. The method includes, for a current block having a predetermined number (Mv) of lines and number (Mh) of columns: decoding coefficients of the current block from coded data; decoding an index representative of an identifier of a transform among a plurality of transforms and identifying the transform, a transform being expressed as a vertical subtransform of size Mv*Mv and a horizontal subtransform of size Mh*Mh; transforming the current block into a decoded block transformed, from the transform obtained, by successive application of the vertical subtransform and then the horizontal subtransform or respectively of the horizontal subtransform and then the vertical subtransform; and reconstructing the image from the transformed decoded block. The transforming includes: a modified use of core sub-transform coefficients, their absolute values being retained.

Abstract: A method for authenticating a user of a terminal equipment connected to a communication network, for access from this terminal equipment to a remote service hosted by a server equipment connected to the network. The method includes the following steps, implemented by the server: authenticating the user from credentials; in the event of successful user authentication, authenticating the client equipment from credentials stored in a first memory of the server in association with the user's credentials, including a command to render a first pattern, the command including parameters describing the first pattern and rendering the first pattern received from the client equipment, so-called reference pattern; deciding on authenticating the client equipment according to the evaluated score, a successful authentication being decided when the match score is greater than a predetermined threshold; and following the authentication decision, updating the credentials of the terminal equipment.

Abstract: Disclosed is a method for digitally generating a hologram in a screen plane of a hologram display device, including: obtaining intensity and depth maps of the scene corresponding to user viewpoint; projecting the points of the intensity map on planes parallel to the screen plane in a reference frame of the screen, one plane associated with one depth value of between minimum and maximum values of the depth map, a point of the intensity map projected on the plane of the planes associated with the depth value of the point in the depth map; compensating for distortion by modifying the planes of the scene, a point of one plane, called image point of an object point by conjugation of the convergent lens, being replaced by the object point; from the modified planes, propagating a complex sampled light wave to the screen plane and summation of the propagated light waves.

Abstract: A method for generating a pulse-position-modulated signal. The signal includes a temporal succession of waveforms among Ns waveforms obtained by time shift that is an integer multiple of an elementary time duration Tc. The method includes the following steps executed for a k rank symbol among Ns symbols: obtaining, a set of N modulation coefficients cl(k), a modulation coefficient of index n, cn(k), being expressed as the product of a reference modulation coefficient cn(r) coming from the Fourier series decomposition of a reference waveform associated with a symbol of rank r multiplied by a phase shift term the argument of which is proportional to n; and generating M temporal samples of a k-th waveform carrying the symbol of rank k by Fourier transformation of said set of N modulation coefficients cl(k).

Abstract: A method of decoding an encoded data stream representing at least one image subdivided into blocks. The method includes, for a current block of the image, and for each of at least two prediction modes available to predict the current block, obtaining a predictive block associated with the available mode; building a list having at least one of the available modes; for at least one mode included in the list, called a current mode, determining a distance measurement between the predictive block associated with the current mode and the other predictive blocks associated with the other available modes and obtained for the current block; modifying the list modified as a function of the determined measurement; decoding information identifying, for the current block, a prediction mode from the modified list from the encoded data stream; and rebuilding the current block from the predictive block associated with the identified prediction mode.

Abstract: Encoding a digital image divided into a plurality of blocks of pixels processed in a defined order, including the following steps, implemented for a current block, with preset sizes: predicting values of the current block from at least one block previously processed; calculating a residual block by subtracting the predicted values from the original values of the current block; obtaining a residual block by applying a transform to pixels of the residual block, said transformed residual block comprising coefficients; encoding the transformed residual block; calculating at least one characteristic representative of at least one transformed residual coefficient of the current block; determining initial identification data representative of a sub-list of at least one transform associated with said at least one calculated characteristic; and verifying that the transform applied to the current block is part of the sub-list identified by the initial data.

Abstract: A method for decoding a coded data stream representative of at least one image, the image being divided into blocks, a set of at least two prediction modes being available for predicting a current block. The method includes: obtaining at least two categories of prediction modes from the set; eliminating at least one category in accordance with at least one first predetermined elimination criterion; updating the categories not eliminated by deleting prediction modes that are common with the at least one eliminated category; and decoding, from the data stream, an information identifying for the current block a prediction mode among the modes of the updated categories.

Abstract: A method for coding a digital image divided into blocks. The method includes, for a current block: processing the current block to provide a vector of transformed coefficients; selecting a sequence of M signs of coefficients to be predicted in the coefficient vector, M being an integer greater than or equal to 2; predicting values of the signs from a plurality of assumptions of combinations and a cost function; and for a sign of the sequence, coding an indicator representing a difference between its actual value and its predicted value. The predicting includes, for at least one second, current assumption: obtaining a pixel vector associated with the current assumption, by linear combination of at least one pixel vector associated with a first assumption and at least one pattern vector obtained from the vector of transformed coefficients; an calculating the cost function for the current assumption from the pixel vector obtained.

Abstract: A method for decoding a stream having first and second portions portion and representing an image divided into blocks. The method includes a sequence test having a predetermined non-zero number of bits, including two at the power of the predetermined number (2N) iterations of the following substeps, for a current block: obtaining a sequence distinct from sequences already tested; decoding and reconstructing a version of the current block from the obtained sequence and from coded data in the first portion; evaluating a likelihood measurement associated with the reconstructed block; decoding information characteristic of a first sequence including the predetermined number of binary symbols from the second portion; selecting a sequence from the sequences tested, based on the likelihood measurements and the decoded information, the selected sequence being identified as the first sequence; and decoding and reconstructing the current block from the first sequence and the first portion.

Abstract: A method for decoding a current block of a digital image. The method includes: decoding coefficients of the current block; and transforming the current block into a decoded block, by implementing a first sub step to produce an intermediate block, that applies to the column and row vectors of the current block, and a second substep to produce a block of pixels that applies to the row and column vectors of the intermediate block, resulting from the first substep; and rebuilding the image from the decoded block. At least one of the first and second substeps includes, for an input row or column vector: forming a first subvector of size K<N or N respectively from adjacent elements of the input vector; transforming the first subvector into a first transformed subvector by applying a partial subtransform of size K×K; and building the transformed vector by inserting the first transformed subvector.

Abstract: A method for coding a digital image divided into blocks. The method includes, for a current block: processing the current block to provide a vector of transformed coefficients; selecting a sequence of M signs of coefficients to be predicted in the coefficient vector, M being an integer greater than or equal to 2; predicting values of the signs from a plurality of assumptions of combinations and a cost function; and for a sign of the sequence, coding an indicator representing a difference between its actual value and its predicted value. The predicting includes, for at least one second, current assumption: obtaining a pixel vector associated with the current assumption, by linear combination of at least one pixel vector associated with a first assumption and at least one pattern vector obtained from the vector of transformed coefficients; an calculating the cost function for the current assumption from the pixel vector obtained.

Abstract: A method for demodulating a received signal resulting from the modulation of a basic chirp signal including estimating of a symbol carried by the received signal, implementing the following sub-steps: determining N decision components from the received signal and from a reference chirp signal obtained by modulating the basic chirp signal by a reference symbol corresponding to a symbol of rank r, a decision component of index I, denoted as a component Dl, being a function of a term, the phase of which depends quadratically on I, with I being an integer from 0 to N?1; and deciding the rank {circumflex over (k)} of the symbol carried by the received signal, from the decision component, of index k, denoted as a component Dk, having an extremum value among the N decision components.

Abstract: A method for encoding a digital image divided into a plurality of blocks of pixels. The method includes, for a current block: processing the current block to provide a set of description elements; selecting a subset of description elements to be predicted; ordering the description elements of the subset into an ordered sequence; and encoding the elements of the sequence. Encoding includes scrolling the elements of the sequence and includes, for a current element: selecting a combination of predicted values of the description elements of the current sequence from a plurality of possible combinations based on a predetermined cost criterion and from the second element, values of description elements previously processed of the initial sequence; predicting the current element of the sequence by its value in the selected combination; and encoding an indicator representative of a difference between the actual value of the current element and its predicted value.

Abstract: A method for processing a digital image including image elements having a first luminance component. The first luminance component has a first value in a first predetermined interval. The display can render second values of second luminance components included in a second predetermined interval. The method includes: determining information representative of image brightness perceived by an observer, based on the first values of the first luminance component; calculating an expansion exponent as a function of the determined brightness information; transforming the first luminance components into the second luminance components, including calculating an intermediate luminance value by applying the calculated expansion exponent to the first luminance component value, multiplying the intermediate value by a length of the second interval, and obtaining the second value of the second luminance component based on the multiplied intermediate luminance value.

Abstract: Processing a request for delivery of data sent by a customer terminal to a remote server via a telecommunication network. The terminal accesses the network by at least two links of distinct access types. The data is encoded in a stream with a predetermined bit rate, which is cut into segments. Processing includes, for a segment of the stream: determining a sub-segment size based on the number of links and a size of the data stream to be delivered; calculating a partitioning of the segment into sub-segments according to the set size and a distribution of the sub-segments on the plurality of links, according to a scheduling of the sub-segments in the partitioning and a time constraint; and sending a plurality of sub-segment transmission requests to the server over the plurality of links, each request including an identifier of the segment and indexes of a sub-segment start and end.

Abstract: A method for digitally generating a hologram plane from a three-dimensional scene, cut into a plurality of planes parallel to the hologram plane. The method includes for a current plane: counting a number of points of the non-zero amplitude scene; choosing a first or second technique for propagating a light wave emitted by the current plane as a function of a number of points of non-zero amplitude included in the current plane and with a preset threshold value, the first, point-based technique calculating the propagation of a sum of light waves emitted by point sources constituted by the points of the scene portion of a non-zero amplitude of the current plane on a following plane, and the second, field-based technique, globally calculating a light wave emitted by the scene portion situated in the current plane on a given plane; and processing the current plane according to the chosen propagation technique.

Abstract: A method is proposed for generating an OFDM type multicarrier signal including OFDM blocks constituted by M carriers modulated by source symbols. The method includes the following steps: interleaving the M symbols of a block of source symbols into R sub-blocks of N interleaved symbols; obtaining a block of M time domain samples corresponding to the block of M source symbols; forming a peak vector containing N maximum amplitudes determined from among the M samples; attenuating the extrema of each sub-block of N time domain samples corresponding to the R sub-blocks of N interleaved symbols by a correction of symbols taking account of the peak vector and delivering R sub-blocks of N corrected interleaved symbols; de-interleaving the R sub-blocks of N corrected interleaved symbols delivering a block of M corrected source symbols; generating an OFDM block of the signals corresponding to the block of M corrected source symbols.

Abstract: A method for processing an intrusion in a communication network including a plurality of node equipment, including a current node, which: discovers of a neighborhood of the current node, including assigning a resilience group to the neighboring node, according to at least one piece of information representative of a resilience level of the neighboring node to at least one type of attack; detecting an intrusion affecting at least one suspect node of the neighborhood of the current node; establishing a consensus concerning the at least one suspect node in a neighborhood by counting a number of resilience groups having detected the intrusion in the neighborhood of the suspect node and a total number of resilience groups represented in the neighborhood of the suspect node; and deciding to change a status of the suspect node based on a result of the consensus by comparison of both numbers.