Abstract: The invention relates to a method for decoding an image based on a base layer (Cbase) and enhancement information (Iam), said method comprising the following steps: decoding said base layer (Cbase) in order to obtain at least one base component (Ydecbase, Udecbase, Vdecbase), oversampling the at least one base component (Ydecbase, Udecbase, Vdecbase) in order to obtain at least one oversampled component (Ysurech, Usurech, Vsurech), decoding the enhancement information (Iam) by means of a part (B) at least of artificial neural network in order to obtain enhancement values (Vam), reconstructing the image based on the at least one oversampled component (Ysurech, Usurech, Vsurech) and the enhancement values (Vam). The invention also relates to associated encoding method, electronic decoding device, electronic encoding device and signal.

Abstract: A method for interpolating a sound field captured by a plurality of N microphones each outputting the encoded sound field in a form including at least one captured pressure and an associated pressure gradient vector. Such a method includes an interpolation of the sound field at an interpolation position outputting an interpolated encoded sound field as a linear combination of the N encoded sound fields each weighted by a corresponding weighting factor. The interpolation includes an estimation of the N weighting factors at least from: the interpolation position; a position of each of the N microphones; the N pressures captured by the N microphones; and an estimated power of the sound field at the interpolation position.

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 digital interpolation filter delivering a series of output samples approximating a signal x(t) at sampling instants of the form (n+d)T s based on a series of input samples of the signal x(t) taken at sampling instants of the form nT s. Such a filter implements a transfer function in the Z-transform domain, H c<i/>d (Z?1), expressed as a linear combination between: a first transfer function H 1 d<i/>(Z?1) representing a Lagrange polynomial interpolation of the input samples implemented according to a Newton structure (100); and a second transfer function H 2 d (Z?1) representing another polynomial interpolation of the input samples implemented according to another structure comprising at least the Newton structure; the linear combination being a function of at least one real combination parameter c.

Abstract: A method for encoding or decoding at least one image, an image being split into blocks of elements. The method includes, for at least one block: splitting the block into at least two areas; and processing at least one of the areas. The processing includes scanning the elements of the area according to a predetermined scanning order, and for at least one scanned element, called a current element: selecting at least one predictor element previously encoded or decoded according to a prediction function; and predicting the current element: from the at least one predictor element, if the at least one predictor element belongs to the area; or from at least one replacement value, otherwise.

Abstract: A method for forming an image sequence that is an output sequence, from an input image sequence, is provided. The input image sequence has an input spatial resolution and an input temporal resolution. The output sequence has an output temporal resolution equal to the input temporal resolution and an output spatial resolution equal to a predetermined fraction 1/N of the input spatial resolution by an integer number N higher than or equal to 2. The method, implemented for a sub-sequence of the input frame sequence that is a current input sub-sequence and including a preset number of images, includes: obtaining a temporal frequency that is an image frequency, associated with the current input sub-sequence; processing the current input sub-sequence to obtain an output sub-sequence; and inserting the output sub-sequence and the associated image frequency into an output container.

Abstract: A method for predicting a three-dimensional representation in a three-dimensional scene, using one or more two-dimensional representations, obtained from at least one image generated by a camera. The method includes obtaining a forest of regression trees, and for the at least one image: extracting a 2D representation associated with one or more positions within the image; predicting a 3D representation, corresponding to the extracted 2D representation, using the regression tree forest includes a set of possible associations between at least one 2D representation and a 3D representation, each possible association resulting from a predictive model; evaluating one or more of the possible associations of the regression tree forest, according to a predetermined confidence criterion; and updating the regression tree forest including a deactivation of one or more possible associations, depending on the evaluation of the possible associations.

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 estimating a camera pose in a frame of reference of a three-dimensional scene, including: obtaining an image of colour intensities of the scene; extracting points of interest, which are invariant by geometric transformation of the image; forming patches in the image, each including an extracted point of interest; predicting 3D locations of the points of interest by applying an automatic prediction system, trained by a training set including patches from images acquired from plural points of view, an image being associated with a 2D position of its point of interest in a frame of reference of the image and with a 3D position of its point of interest in the frame of reference of the scene; estimating the pose of a camera, by mapping the 2D positions of the points of interest and reprojections in the current image frame of reference of the predicted 3D locations.

Abstract: Disclosed is a method for generating a digital hologram representing a 3D scene including an object, an object being defined by points and their associated intensity. For each object, a prior step of calculating an “omnidirectional” angular spectrum of the light field emitted by an object in the scene on the surface of a geometric solid centered on the object, a surface of the solid being sampled according to a predetermined grid, a sample of the grid being associated with a vector frequency; for the scene, the following steps: —obtaining a pose of an observer in the world frame of reference; —deriving the hologram from the scene as a function of the pose obtained from the “multidirectional” angular spectra calculated for each object. The step of calculating an angular spectrum of the light field for each object of the scene takes into account predetermined viewing directions.

Abstract: A method for estimating a wireless communication channel between a transmitter and a receiver, including a plurality of paths for propagation of a wave, at least one of the transmitter and the receiver being formed of a plurality of antennas. The method includes: for at least one path, determining a characteristic matrix, which depends on a first element representative of at least one propagation direction associated with the path, and a second element representative of a propagation distance associated with the path; and estimating the communication channel from the at least one obtained characteristic matrix.

Abstract: A method for decoding an encoded data stream representative of at least one image, which is divided into blocks. The decoding method includes, for a current block: evaluating a plurality of value hypotheses of at least one description element of the current block, by calculating a likelihood measurement per hypothesis; calculating a disparity in the likelihood measurements obtained; determining at least one parameter of a decoder based on the calculated disparity; decoding, using the determined decoder, complementary information for identifying at least one of the hypotheses; and identifying at least one of the hypotheses using the decoded complementary information and obtaining a value of the at least one description element for the current block, from the at least one identified hypothesis.

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.