Abstract: Groups of streams of encoded data having different predetermined bit rates are selected for transmission to a client application based on available bandwidth. Common values for at least a part of the decoding parameters are determined so that the decoder can use the same decoding parameter values for decoding stream elements within each group of streams of various bit rates.

Abstract: The invention relates to a Push-to-Talk application enabling the transmission of different types of content, for example voice content and video content. In Push-to-Talk applications, only one user of a group can talk at a time and a floor control procedure is used to control access to the floor by the users of the group. According to the invention, separate implementations of the floor control procedure are used with the framework of one single session for managing access to the floor for the transmission of different types of content. For example a first implementation of the floor control procedure is used to manage floor access for the transmission of voice content and a second independent implementation of the floor control procedure is used to manage floor access for the transmission of picture content.

Abstract: The invention proposes a method of transmitting a multimedia content from a server to a client device upon request of the client device, said method allowing adaptation of the characteristics of the encoder used for encoding the multimedia content based on the network transmission rate and/or client preference or preferences. The method of the invention consists in encoding the content with various encoder characteristics, thereby providing several encoded multimedia contents, slicing the encoded multimedia contents, thereby providing a plurality of file-based contents, downloading the content file by file while switching from one encoded multimedia content to another so as to change the encoding characteristics, thereby adapting to the network transmission rate and/or client preferences.

Abstract: The present invention relates to a method of receiving a multimedia signal in a communication apparatus, said multimedia signal comprising at least a sequence of video frames (VF) and a sequence of audio frames (AF) associated therewith. Said method comprises the steps of: processing (21) and displaying (25) the sequence of audio frames and the sequence of video frames,—buffering (24) audio frames in order to delay them, detecting (22) if the face of a talking person is included in a video frame to be displayed, selecting (23) a first display mode (m1) in which audio frames are delayed by the buffering step in such a way that the sequence of audio frames and the sequence of video frames are synchronized, and a second display mode (m2) in which the sequence of audio frames and the sequence of video frames are displayed without delaying the audio frames, the first display mode being selected if a face has been detected and the second display mode being selected otherwise.

Abstract: Method of synchronizing the playback of an audio broadcast on a plurality of network output devices. The present invention relates to method of synchronizing the playback of an audio broadcast on a plurality of network output devices. Said method comprises the steps of: detecting (11) a set of network output devices located in a same neighborhood which are able to play the audio broadcast, selecting (12) at least one network output device from among the set of network output devices, preventing (13) the network output devices of the set other than the at least one selected network output device to play the audio broadcast.

Abstract: The present invention relates to a method of visualizing a large still picture on a display having a size smaller than the large still picture, said method comprising the steps of dividing the large still picture into a set of pieces, said pieces having a size substantially equal to the display size; ranking the pieces of the large still picture according to a predetermined scanning order; and encoding the set of pieces using a predictive block-based compression technique according to said predetermined scanning order so as to obtain a video sequence.

Abstract: The present invention proposes a media packet structure comprising an insensitive part (ISP) comprising a block of media data (BMD) and a sensitive part (SP), said sensitive part being protected by a checksum (CS), said sensitive part comprising error correction codes (FEC) for correcting the block of media data (BMD) contained in said insensitive part (ISP). With the invention, media packets with damages in their insensitive part are not rejected, but repaired using the error correction codes (FEC).

Abstract: The invention proposes to divide a content to be transmitted via a network into a set of slices and to generate a set of files from this set of slices. The slices (or the files) are encrypted before downloading in such a way that the client cannot use the slice (or the file) before having acquired the associated decryption key. The invention thereby allows protecting a downloaded content on a slice-by-slice basis (or on a file-by-file basis) rather than protecting a downloaded content as a whole. The transmission (in download mode) between the server and the client is ruled by the HTTP protocol that is accepted by all firewalls and NAT. Consequently, the transmitted content is accessible for any client device that has access to the Web without restriction. Advantageously, the slices can be decoded independently of each other.

Abstract: The invention applies to the transmission of a multimedia content from a server to a client terminal. The multimedia content is available from the server as one or more sets of files. Upon reception of an initial request from the client, the server sends a document back to the client, said document causing the client to repetitively send fetching request. Upon reception of a fetching request, the server selects the file to download.

Abstract: The invention relates to a method of streaming multimedia for providing seamless stream switching. The method consists in streaming multimedia data from a server (15) to a client (14) over a network (13) having a variable bandwidth. The client is intended to decode a subset of streams within a set of streams having various predetermined bit rates. The decoded subset of streams has bit rates compatible with the network bandwidth. The method comprises the steps of configuring the client so that the client can decode all the streams within the set of streams, playing all the streams within the set of streams and muting all the streams within the set of streams, except the subset of streams.

Abstract: The method of streaming multimedia data over a network having a variable bandwidth comprises the steps of encoding data coming from a multimedia source and supplying a set of encoded streams formed with stream elements containing encoded multimedia data. The encoded streams have various predetermined bit rates associated with specific decoding parameter values to be transmitted to a client application decoder for enabling the client decoder to decode the stream elements with respect to their specific decoding parameter values. The encoding step comprises a preliminary step of determining common values for at least a part of the decoding parameters so that the decoder can use the same decoding parameter values for decoding streams elements within at least a group of streams, and a step of building said group of streams, to which common decoding parameter values are assigned.

Abstract: The invention relates to a method and a device for encoding video data consisting of one or several bitstreams according to the MPEG-4 standard. In order to avoid any problem when mapping the video elements into the system elements, a specific alignment/fragmentation mechanism is chosen. According to this mechanism, when said video bitstreams are encoded using the syntax mode corresponding to the fragmentation of the Video Object Planes (VOPs) contained in said video data into Video Packets (VPs)and of Video Packets into Data Partitions (DPs), a Video Data Partition is mapped into one or more SL packets (SL1, SL2, SL3, SL4, . . .), the first Video Data Partition (DP1) start is always mapped to an SL packet start, and the last SL packet transporting the first Data Partition includes the separation marker and up to 7 subsequent bits of the second Data Partition (DP2) in order to obtain byte alignment, the next SL packet starting on the next bit of the second Data Partition.

Abstract: The invention relates to a method and a device for encoding video data consisting of one or several bitstreams according to the MPEG-4 standard. In order to avoid any problem when mapping the video elements into the system elements, a specific alignment/fragmentation mechanism is chosen. According to this mechanism, when said video bitstreams are encoded using the syntax mode corresponding to the fragmentation of the Video Object Planes (VOPs) contained in said video data into Video Packets (VPs) and of Video Packets into Data Partitions (DPs), a Video Data Partition is mapped into one or more SL packets (SL1, SL2, SL3, SL4, . . . ), the first Video Data Partition (DP1) start is always mapped to an SL packet start, and the last SL packet transporting the first Data Partition includes the separation marker and up to 7 subsequent bits of the second Data Partition (DP2) in order to obtain byte alignment, the next SL packet starting on the next bit of the second Data Partition.

Abstract: This data receiver (1) is intended to receive many digital programs coming from the Internet, for example. This receiver comprises a plurality of program receiving devices (40, 41, 42, 43, 44, . . . ) for receiving programs according to a pre-established criterion. A remote control box (32) displays a part of the programs. A shift of this list clears and loads one of the receiving devices on the basis of another program.

Abstract: The present invention relates to a multimedia player providing a generic and easy to use mechanism for accurate task scheduling. Said multimedia player processes a encoded digital data stream (IS) in order to supply audio and video signals (SO, SC) to an audio-visual production system (LS, MON). The multimedia player in accordance with the invention comprises a demultiplexer (DEMUX) for splitting the encoded digital data stream into an audio stream (AS) and several video streams (VS1 to VSn). The multimedia player also performs the tasks of audio decoding and rendering (DR), to decode (ADEC) the audio stream, to filter the decoded audio frames (AF) provided by the decoding and to render (AREN) said audio frames; decoding (DEC) the video streams, to provide video objects whose decoded video frames (VF1 to VFn) are stored in video buffers (BUF1 to BUFn); and rendering (REN) the decoded video frames stored in the video buffers.

Abstract: The invention relates to an MPEG-4 encoder in which the encoded content is stored in the .mp4 file format together with specific additional hint tracks. These tracks include a pre-segmentation information indicating how to fragment the encoded data, organized in Access Units, in order to match the size of the packets used for a packetized transmission (ATM, MPEG-2 TS, IP, . . . ). According to the invention, the fragmentation information, structuring the coded bitstream into independent entities, is stored during encoding in a fragment structure independent from the .mp4 file. The invention also relates to a coded signal available at the output of such an encoder, and to a terminal receiving said coded signal and reading it according to a file structure having the appropriate syntax.

Abstract: Information is extracted from a hand-written text by means of a graphics tablet (1). The curves thus obtained make it possible to recognize primitives, namely basic forms, representing a way of writing a part of a letter. More accomplished forms, called allographs, are constructed from primitives in order to construct a letter or in even a group of two or three letters. When the series of codes corresponds to a known object from a dictionary of allographs (3), each defined by the sequence of codes of its primitives, the corresponding allograph is recognized. The genetic algorithm is used to improve the population of strings. "Descendants", obtained by combining two starting strings (7), are constructed from a limited-quantity selection of strings (9), from among which descendants the most appropriate are in turn chosen, this gradually optimizing the population. Applications: recognition of cursive writing.

Abstract: On the basis of a device without hidden neurons, arbitrary samples are taken from a set of learning samples so as to be presented as objects to be classified. Each time if the response is not correct, a hidden neuron (H.sub.i) is introduced with a connection to the output neuron (O.sub.j) of the class of the sample, whereas if the response is correct, no neuron whatsoever is added. During this introduction phase for hidden neurons, the neurons are subdivided into groups by searching for each of the introduced neurons whether it falls within an existing group, in which case it is incorporated therein; otherwise a new group is created around this neuron. The association with a group is defined as a function of the distance from the "creator" neuron. Application: character recognition systems.

Abstract: On the basis of a device without hidden neurons, arbitrary samples are taken from a set of learning samples so as to be presented as objects to be classified. Each time if the response is not correct, a hidden neuron (H.sub.i) is introduced with a connection to the output neuron (O.sub.j) of the class of the sample, whereas if the response is correct, no neuron whatsoever is added. During this introduction phase for hidden neurons, the neurons are subdivided into groups by searching for each of the introduced neurons whether it falls within an existing group, in which case it is incorporated therein; otherwise a new group is created around this neuron. The association with a group is defined as a function of the distance from the "creator" neuron. This device could be applied in character recognition systems as one example.

Abstract: Method and device having a neural network for classifying data, and verification device for signatures.The device includes a neural network with an input layer 3, an internal layer 4, and an output layer 5. This network is designed to classify data vectors to classes, the synaptic weights in the network being determined through programming on the basis of specimens whose classes are known. Each class is defined during programming as corresponding to a set of neurons of which each represents a domain which contains a fixed number of specimens. The network includes a number of neurons and synaptic weights which have been determined as a function of the classes thus defined.