Abstract: A video encoder unit receives a video signal to encode along with auxiliary services such as audio streams and/or data streams. While the auxiliary streams are allotted a fixed bandwidth, the video encoder determines a required video bandwidth, which must be allocated in response to the request by a central allocator. Where economies are made in the auxiliary services for example by transmitting stereo audio instead of surround sound for example, the bandwidth requested from the central allocator is inflated by an amount corresponding to a proportion of the economized bandwidth. The extra bandwidth allocated on this basis may then be used for improving the quality of video encoding, and/or reserved for the transmission of asynchronous data.

Abstract: The invention relates to a device for coding video data comprising means to code a video stream as groups of pictures, each group of pictures comprising at least one description unit relevant to the coding of the said group of pictures. According to the invention, the coding device comprises means to insert in the stream of data at least one message indicating whether the description unit of the current group of pictures is identical to the description unit relevant to the preceding group of pictures. The invention also relates to a device for decoding video data comprising means to decode a stream of data coded with a device according to one of the preceding claims. According to the invention, the decoding device comprises means to analyze the said messages, means to decode the at least one next description unit if the said message indicates that this unit is different from the preceding description unit, otherwise, if it is identical, not to decode it.

Abstract: The present invention relates in particular to a synchronization system and method. The synchronization system comprises a specification unit for specifying synchronization signals associated with an audiovisual program, the latter comprising an audiovisual content and control information, a recognition unit for recognizing the synchronization signals in a transmitted stream carrying this program, by recognition of at least one extracted portion of the audiovisual content, and an activation unit triggering an action in case of detection of these signals. The specification unit prepares and transmits to the recognition unit recognition elements making it possible to obtain this extracted portion, as well as at least one action timeout lag in case of detection of the synchronization signals. The recognition or activation unit then delays the triggering of this action according to the lag transmitted, in case of detection of the synchronization signals.

Abstract: The present invention relates in particular to a synchronization system and process. The synchronization system comprises a specification unit for specifying synchronization signals associated with an audiovisual program, the latter comprising an audiovisual content and control information, a recognition unit for recognizing these synchronization signals in a stream carrying this program transmitted via a broadcasting network, by recognizing at least one extracted portion of the audiovisual content, and an activation unit triggering an action in case of detection of these signals. The specification unit prepares and transmits to the recognition unit recognition elements making it possible to obtain this extracted portion, which comprise instructions for extracting the portion of content from at least one stream of an audiovisual program previously received by the recognition unit via the broadcasting network. In variants, the recognition elements are obtained independently of the specification unit.

Abstract: The invention relates to a method for coding a sequence of images, comprising the following steps: determining, for the image data, the prediction image data from reference image data, calculating residual data from image data and prediction image data, quantizing the residual data with a quantization step, reconstructing the image data into reconstructed image data, filtering the reconstructed image data according to at least one filtering parameter with a view to their use as reference image data, coding the quantized residual data, selecting a function representing the variations of at least one filtering parameter according to a quantization step value of a set of at least two functions from a predetermined value representative of a filtering intensity, determining the value of at least one filtering parameter from the function selected and the quantization step.

Abstract: The invention relates to a method for coding a sequence of images, comprising the following steps: determining, for the image data, the prediction image data from reference image data, calculating residual data from image data and prediction image data, quantizing the residual data with a quantization step, reconstructing the image data into reconstructed image data, filtering the reconstructed image data according to at least one filtering parameter with a view to their use as reference image data, coding the quantized residual data, selecting a function representing the variations of at least one filtering parameter according to a quantization step value of a set of at least two functions from a predetermined value representative of a filtering intensity, determining the value of at least one filtering parameter from the function selected and the quantization step.

Abstract: The invention concerns a method for transmitting binary data in a video transmission system. The method comprises the steps of providing ATVEF announcements on a first predefined IP multicast address; providing ATVEF trigger and/or content transmission on a first range of IP multicast addresses; providing non-ATVEF announcements on a second predefined multicast address different from said first address; and providing non-ATVEF data transmission on a second range of IP multicast addresses, exclusive of the first range. The invention also concerns an emitter and a receiver for implementing the method.

Abstract: The method is it comprises the following steps: determination of the prediction window type related to the motion vector, non-outgoing or outgoing according to whether the prediction window is positioned entirely or in part inside the reference image. if the prediction window is of outgoing type, filling a prediction buffer area having dimensions at least equal to that of the prediction window and positioned so as to include the prediction window, with the pixels of the reference image that are common to the prediction area and, for the remaining part, by copying, from said pixels, those located on the edge of the image, calculating the predictor from the pixels of the buffer area located in the prediction window. The applications relate to compression in H 264 or MPEG 4 part 10 format.

Abstract: The present invention concerns a device and a process for signing digital streams, each of them comprising contents, related to audiovisual information, and a signaling. The device applies encrypting to selectively determined descriptors of the signaling, called authenticated descriptors, to obtain signature. The invention also concerns corresponding authentication device and process. Application to authentication of DVB/MPEG digital streams, notably for MHP.

Abstract: The invention relates to a device for coding video data comprising means to code a video stream as groups of pictures, each group of pictures comprising at least one description unit relevant to the coding of the said group of pictures. According to the invention, the coding device comprises means to insert in the stream of data at least one message indicating whether the description unit of the current group of pictures is identical to the description unit relevant to the preceding group of pictures. The invention also relates to a device for decoding video data comprising means to decode a stream of data coded with a device according to one of the preceding claims. According to the invention, the decoding device comprises means to analyse the said messages, means to decode the at least one next description unit if the said message indicates that this unit is different from the preceding description unit, otherwise, if it is identical, not to decode it.

Abstract: The invention relates to a method and a device for coding video data comprising means for coding the pictures in data groups. According to the invention, the device comprises means for inserting, into the coded data groups, a message comprising parameters originating from the coding of the said group and allowing, during a subsequent decoding, a reconstruction of the said data in the event of error during the coding or during the decoding.

Abstract: The invention relates to a device and a method for coding video data. The device comprising means for coding each picture in slices of pictures, each slice being coded independently of the other slices. According to the invention, the device comprises means for inserting into the data stream at least one message indicating the structure relating to the breakdown of the pictures into slices. The invention also relates to a system for decoding and a method for decoding video data, the said video data having been coded in slices, each of the slices being coded independently of the other slices. According to the invention, the coding system comprises means for analysing the video data in order to ascertain the breakdown of the data into slices, means for decoding the video data slice by slice, means for reconstructing the various video data after they have been decoded in order to reconstruct the decoded video data.

Abstract: The present invention relates in particular to a synchronization system and method. The synchronization system comprises a specification unit for specifying synchronization signals associated with an audiovisual programme, the latter comprising an audiovisual content and control information, a recognition unit for recognizing the synchronization signals in a transmitted stream carrying this programme, by recognition of at least one extracted portion of the audiovisual content, and an activation unit triggering an action in case of detection of these signals. The specification unit prepares and transmits to the recognition unit recognition elements making it possible to obtain this extracted portion, as well as at least one action timeout lag in case of detection of the synchronization signals. The recognition or activation unit then delays the triggering of this action according to the lag transmitted, in case of detection of the synchronization signals.

Abstract: The present invention relates to a conditional decision device and method for the execution of services received, having predetermined life spans. This device receives and identifies information relating to computer programs required for the execution of these services. It checks the local availability of these programs and allows the services to be executed if the associated programs are available locally. Furthermore, it is capable of triggering a downloading of the programs when the latter are not available locally, and allowing or preventing such a download, at least according to information associated with the services. The invention also relates to a device and a method for compiling associated messages. Application to ATVEF and MHP standards.

Abstract: The present invention concerns a device and a process for signing digital streams, each of them comprising contents, related to audiovisual information, and a signaling. The device applies encrypting to selectively determined descriptors of the signaling, called authenticated descriptors, to obtain signature. The invention also concerns corresponding authentication device and process. Application to authentication of DVB/MPEG digital streams, notably for MHP.

Abstract: The present invention relates in particular to a synchronization system and process. The synchronization system comprises a specification unit for specifying synchronization signals associated with an audiovisual programme, the latter comprising an audiovisual content and control information, a recognition unit for recognizing these synchronization signals in a stream carrying this programme transmitted via a broadcasting network, by recognizing at least one extracted portion of the audiovisual content, and an activation unit triggering an action in case of detection of these signals. The specification unit prepares and transmits to the recognition unit recognition elements making it possible to obtain this extracted portion, which comprise instructions for extracting the portion of content from at least one stream of an audiovisual programme previously received by the recognition unit via the broadcasting network. In variants, the recognition elements are obtained independently of the specification unit.

Abstract: The present invention relates to a process for synchronizing the transmission of programs to users and the incorporation of transmission contents into said programs. It also applies to corresponding devices and products. According to the synchronizing process, programs enhanced with the contents are produced by sending command instructions to a transmission device and to a transmission server in a time-organized manner, and by incorporating forthwith the contents produced by the server into the programs produced by the device. Instructions relating to processings of data and which are incomprehensible to this server are in particular submitted to the latter, which routes them immediately to a service operator. The latter immediately executes the commands emanating from these instructions. The transmission of the programs is thus synchronized with the operations relating to the data processings.

Abstract: The present invention relates to a security device (3) and process for protecting messages (MSG) despatched to a receiver (2) comprising means of control of identification (21) by a modifiable current identification key (K′i). It also relates to a corresponding device (4) and a corresponding process for identifying messages. The security device comprises a unit for control of enciphering (11) of at least a part of each of these messages by means of a modifiable current enciphering key (Ki), in such a way as to produce a signature added to the message. It also comprises a unit (12) for changing the current enciphering key, selecting this key from a predetermined set (16) of available enciphering keys (K1 Kn), as well as a unit (13) for registering a key identifier (KeyID) in this message.

Abstract: The invention concerns a method for transmitting binary data in a video transmission system. The method comprises the steps of providing ATVEF announcements on a first predefined IP multicast address; providing ATVEF trigger and/or content transmission on a first range of IP multicast addresses; providing non-ATVEF announcements on a second predefined multicast address different from said first address; and providing non-ATVEF data transmission on a second range of IP multicast addresses, exclusive of the first range. The invention also concerns an emitter and a receiver for implementing the method.

Abstract: The present invention relates to a device and to a process for transmitting control instructions for access to functionalities of receivers (2), as well as to a corresponding device and process for implementing control instructions.