Abstract: The invention relates to a method of qualitatively evaluating a digital audio signal. It calculates a quality indicator consisting of a vector associated with each time window in real time, in continuous time, and in successive time windows. For example, the generation of a quality indicator vector calculates, for a reference audio signal and for an audio signal to be evaluated, the spectral power density of the audio signal, the coefficients of a prediction filter, using an autoregressive method, a temporal activity of the signal or the minimum value of the spectrum in successive blocks of the signal. To evaluate the deterioration of the audio signal, the method may calculate a distance between the vectors of the reference audio signal and the audio signal to be evaluated associated with each time window.

Abstract: The invention concerns a method for spectral enhancement and a device therefor. The inventive method is a method for enhancing spectral content of a signal having an incomplete spectrum including a first spectral band, the method including the following steps: at least transposing the spectral content of the first band into a second spectral band not included in the spectrum to generate a transposed spectrum signal, with spectrum limited to the second spectral band; transforming the spectrum of the transposed spectrum signal to obtain an enhancing signal; combining the incomplete spectrum signal and the enhancing signal to produce a spectrum enhanced signal. The invention is characterized in that the spectral content is subjected to a whitening step.

Abstract: The invention relates to a method of qualitatively evaluating a digital audio signal. It calculates a quality indicator consisting of a vector associated with each time window in real time, in continuous time, and in successive time windows. For example, the generation of a quality indicator vector calculates, for a reference audio signal and for an audio signal to be evaluated, the spectral power density of the audio signal, the coefficients of a prediction filter, using an autoregressive method, a temporal activity of the signal or the minimum value of the spectrum in successive blocks of the signal. To evaluate the deterioration of the audio signal, the method may calculate a distance between the vectors of the reference audio signal and the audio signal to be evaluated associated with each time window.

Abstract: The invention relates to a method of qualitatively evaluating a digital audio signal. It calculates a quality indicator consisting of a vector associated with each time window in real time, in continuous time, and in successive time windows. For example, the generation of a quality indicator vector calculates, for a reference audio signal and for an audio signal to be evaluated, the spectral power density of the audio signal, the coefficients of a prediction filter, using an autoregressive method, a temporal activity of the signal or the minimum value of the spectrum in successive blocks of the signal. To evaluate the deterioration of the audio signal, the method may calculate a distance between the vectors of the reference audio signal and the audio signal to be evaluated associated with each time window.

Abstract: The invention concerns a method for spectral enhancement and a device therefor. The inventive method is a method for enhancing spectral content of a signal having an incomplete spectrum including a first spectral band, the method including the following steps: at least transposing the spectral content of the first band into a second spectral band not included in the spectrum to generate a transposed spectrum signal, with spectrum limited to the second spectral band; transforming the spectrum of the transposed spectrum signal to obtain an enhancing signal; combining the incomplete spectrum signal and the enhancing signal to produce a spectrum enhanced signal. The invention is characterised in that the spectral content is subjected to a whitening step.

Abstract: The present invention relates to a spectral enhancement method and to an apparatus carrying out this method. The method of the invention enhanced the spectral content of a signal having an incomplete spectrum including a first spectral frequency band, the method comprising the following stages: at least one spectral content transposition of said first frequency band into a second spectral frequency band not included in said spectrum for the purpose of generating a transposed spectrum signal having a spectrum limited to said second spectral frequency band, shaping the spectrum of the transposed spectrum signal for the purpose of producing an enhanced signal, combining an incomplete spectrum signal and the enhanced signal for the purpose of producing an enhanced spectrum signal, characterized in that said spectral content is subject to a stage of whitening.

Abstract: The invention relates to a method of synchronizing first and second digital signals presenting digital elements to be put into correspondence, on the basis of time references. The method includes preliminary synchronization of the two digital signals using time references, by putting time references recognized as having the same value in the first and second digital signals into correspondence; and fine synchronization on the basis of a characteristic parameter obtained from the binary streams of the digital elements, and computed for each of the first and second digital signals.

Abstract: A method enabling a personal computer to be authenticated by a server is provided. The method comprises the step, which includes for the user in launching the execution of a log-on procedure software, introducing personal identifiers providing access to a signature private key for long-term use relative to the duration of the session. The log-on procedure software produces: identification data of the session Id, a public ephemeral module, a public exponent and at least a pair of ephemeral pubic numbers and ephemeral private numbers related by a generic equation of the type: G=Qv (mod n) or G×Qv=1 (mod n), an ephemeral certificate linking, by means of said signature private key, Id and public ephemeral module. The public ephemeral module is of reduced size relative to the signature private key.

Abstract: A method for enabling a personal computer to be authenticated by a server is provided. The method comprises the step, which includes for the user in launching the execution of a log-on procedure software, introducing personal identifiers providing access to a signature private key for long-term use relative to the duration of the session. The log-on procedure software produces: identification data of the session Id, a public ephemeral module, a public exponent and at least a pair of ephemeral pubic numbers and ephemeral private numbers related by a generic equation of the type: Gi?Qiv (mod n) or Gi·Qiv?1 (mod n), an ephemeral certificate linking, by means of said signature private key, Id and public ephemeral module. The public ephemeral module is of reduced size relative to the signature private key.

Abstract: A method is provided for receiving a multicarrier signal in a receiver implementing at least two distinct reception channels. After receiving the multicarrier signal during a first step, and in order to optimize subsequent processing (such as synchronization, confidence computing, . . . ), information representing the reception quality is associated to each corresponding reception channel during a second step. An embodiment of the disclosure relies on a new way of computing this information, called absolute confidence, which takes account on the one hand of the reception quality of the considered channel compared to the other channels (total confidence) and on the other hand of the reception quality of each source data (carrier) compared to the others, in the considered channel (relative confidence), to determine an absolute confidence for each data of each channel.

Abstract: Method of demodulating a signal in a transmission system where the modulation includes several substantially orthogonal subcarriers, the vector of the propagation channel H[n,k] being known, or the received signal including at least pilot symbols emitting reference data. It comprises at least one step of estimating the symbol a[n,k] emitted on the kth subcarrier of the nth symbol of the modulation with the aid of a recombination weighting the various signals received after synchronization and demodulation x[n,k].

Abstract: The invention concerns a system for developing interactive applications transmitted through a network. The system comprises, activated by the operation of a computer, an electronic editor (E) for simulating a display screen of a display monitor, and an interface controlling (MCS) a control module associated with said display monitor. A module generating virtual objects (GOV) specific to the application to be developed is provided, the virtual objects being selected at least among images in point mode, video files, textual files, capable of being edited, displayed, represented by the editor (E) for forming a scene of the pplication. A control module (COR) for correlating event/action pairs is provided, an event corresponding to the imbalance of the state of an operation system and an action corresponding to an initialization or a modification of the display or the representation of one or several scenes constituting the applications.

Abstract: The invention relates to a reception device implementing at least two reception paths supplied with data flows, each conveying the same source symbols, each of said paths comprising estimation means, associating, with each source symbol received, an estimated path value and a corresponding path confidence information element, and comprising means for the combination of said estimated path values into an adapted estimated value, said combination taking account of said path confidence information elements to weight said estimated path values. Said estimation means advantageously comprises means for the estimation of the transmission channel, delivering said path confidence information elements. Said combination means may advantageously associate an adapted confidence information element with each of said adapted estimated values, as a function of said path confidence information elements.

Abstract: To avoid searching for a new location for very high hectometric wave antennas, an antenna according to the invention comprises an existing vertical structure having a height of at least approximately ten meters and including at least one electrically conductive element connected to the ground, and an excitation conductor wire (4a) that is essentially electrically conductive, disposed at least in part in the vicinity of and outside the structure and connected to a emitter (E) so that the structure radiates substantially hectometric waves. The existing structure may be a broadcasting tower, a water tower, a chimney, a lighthouse or a lamp standard, wherein the excitation wire merges visually. The wire can be replaced by a conductive loop a few meters long, magnetically coupled to the structure.

Abstract: The invention provides a method of evaluating the quality of an audiovisual sequence by: a) training, comprising allocating a subjective score NSi to each of N0 training sequences Si (where i=1, 2, . . . , N0) presenting degradations identified by a training vector MO1 which is given to each sequence Si in application of a first vectorizing method, in order to build up a database of N0 training vectors MOi with subjective scores NS1; b) classifying the N0 training vectors MOi into k classes of scores as a function of the subjective scores NS1 that have been allocated to them, so as to form k training sets EA (where j=1, 2, . . . , k) which have k significant training scores NSRj allocated thereto; c) for each audiovisual sequence to be evaluated, generating a vector MO using said first vectorization method; and d) allocating to the audiovisual sequence for evaluation the significant training score NSRj that corresponds to the closest training set EAj.

Abstract: A method of modulating a multicarrier signal involves obtaining a set of 2M representative complex coefficients of transmitted data. 2LM linear combinations are calculated so as to leave 2M obtained complex coefficients. Coefficients of balancing used in these combinations represent a prototype function g(t). The 2LM coefficients are summed in given areas of memory. The 2LM memory sites represent 2L groups of M distinct partial sums. The transmitted samples are sent so as to gradually form M samples to transmit, in the memory sites, over a defined duration.

Abstract: The invention relates to a method of synchronizing two digital data streams with the same content, the method comprising the steps of: a) generating at given intervals for each of the two digital data streams S1 and S2 at least two characteristic numbers expressing at least one parameter characteristic of their content; b) generating from said numbers points D1 and D2 for each of the two streams S1 and S2 representing at least one of said characteristic parameters in a space of at least two dimensions, the points D1 corresponding to the stream S1 and the points D2 corresponding to the stream S2 that are situated in a time period T defining trajectories representative of the data streams S1 and S2 to be synchronized; c) shifting the time periods of duration T assigned to the digital data streams S1 and S2 relative to each other by calculating a criterion of superposition of said trajectories having an optimum value representing the required synchronization; d) choosing the shift between the time periods corres

Abstract: The invention concerns a method for receiving a signal using a multiple carrier and code division multiple access modulation, comprising a demodulating step by application of a mathematical transform of the temporal domain to the frequency domain, a step which consists in equalizing the transformed signal and a step which consists in despreading the equalized signal. The invention is characterised in that said equalizing step takes into account, for each of the components of said transformed signal, perturbations affecting the carrier bearing said component and at least one other of said carriers and at least some of said spread codes.

Abstract: The invention relates to a method for coding an image that is to be coded, characterized in that said method comprises the following steps: definition of a hierarchical mesh structure having at least two levels of interconnected meshing formed from mesh units which are defined by peaks; determination, for each of said mesh units, of information concerning an error between the image which is to be coded and an interpolated image obtained from the peaks of the mesh units pertaining to the level of the meshing of the mesh unit in question; termination (33) of the refinement of mesh units having error information below a first predetermined threshold; implementation of a specific coding (35) for the mesh units having error information above a second predetermined threshold; continuation (34) of the refinement of mesh units having error information above the first predetermined threshold and below the second predetermined threshold.

Abstract: An image coding method for a domain corresponding to at least one portion of an image. A minimal triangular partition covering the domain is defined. A square matrix is associated with each of the source triangles by a first reversible transformation so that each matrix represents a specific source triangle. A second reversible decorrelation transformation is applied to each square matrix, resulting in transformed matrixes. The method may be used in isolation, or as a supplement to another coding of the hierarchic type. A corresponding decoding method is also provided.