Abstract:
A video consisting of data organized in the form of a plurality of images is transmitted in a communication network. The method comprises a step of coding images with motion compensation, which consists in compressing the images of the video and in creating dependencies between compressed images, a step of scheduling the transmission of packets representing the compressed images, which consists in sending the compressed images over the network in a selected order, and a step of controlling the rate of the video. At least one of reconsidering the selected order of sending already compressed but not yet transmitted images and deleting at least one compressed image is performed at the time of coding a new image. Furthermore, the dependencies between the new image to be compressed and the compressed images are selected by taking into account the reconsidered sending order at the time of coding the new image.
Abstract:
To transmit data between a server and at least one client in a communication network, this data having to comply with a first transmission latency, for a first processing to be carried out by a first client, and with a greater second latency, for a second processing to be carried out by a second client: the server determines, from the data, taking account of the variable available bandwidth, a first data stream having a rate compatible with the first latency; it transmits this first stream to the clients; it determines, from the data not included in the first stream, taking account of the variable available bandwidth, a second data stream having a rate compatible with the second latency; and it transmits this second stream to the second client. The calculation of the rate of the first stream takes account of the unsent quantity of data of the second stream.
Abstract:
A method of creating a video sequence representative of a digital video sequence, characterized in that it comprises the following steps: dividing the digital image video sequence into a plurality video sections, for at least one of said video sections of the digital video sequence: selecting at least one video portion of the video section, determining a video segment comprising said at least one selected video portion, associating with the determined video segment at least one item of identification information for identification of the corresponding video section and at least one item of location information for location within the digital video sequence of said at least one video portion included in the segment, and inserting the determined segment in the video sequence representative of the digital video sequence.
Abstract:
A video consisting of data organized in the form of a plurality of images is transmitted in a communication network. The method comprises a step of coding images with motion compensation, which consists in compressing the images of the video and in creating dependencies between compressed images, a step of scheduling the transmission of packets representing the compressed images, which consists in sending the compressed images over the network in a selected order, and a step of controlling the rate of the video. At least one of reconsidering the selected order of sending already compressed but not yet transmitted images and deleting at least one compressed image is performed at the time of coding a new image. Furthermore, the dependencies between the new image to be compressed and the compressed images are selected by taking into account the reconsidered sending order at the time of coding the new image.
Abstract:
A method and device for transmitting data packets from a server to at least one client concerns i) estimating a time lapse between the transmission of a successive first and second packet, on the basis of information relating to the first packet, the information being representative of whether or not the first and second packets transport image data from the same image, and ii) triggering and defining retransmission of the second packet, on the basis of said time lapse. In one embodiment, the client estimates the time lapse on the basis of the type of the second packet and on the basis of statistical results concerning the type of the second packet and requests the retransmission of a packet awaited for a longer time than that time lapse. In another embodiment, the server estimates the time lapse on the basis of the type of payload of a first packet to retransmit and of at least one second packet following the first packet to retransmit and spontaneously retransmits the second packet with the first packet on the basis of that time lapse.
Abstract:
The method of transmission of a datastream representing a sequence of images over a network in which the quantity of information that may be sent per unit of time varies substantially cyclically, said transmission extending over a plurality of cycles, comprises: a step (805 to 807, 809, 810) of determining times for which the quantity of information that may be sent per unit of time over the network is greater, and respectively less, than its average, on the basis of the substantially cyclical past variation in said quantity of information and a step (801 to 805, 812 to 816) of sending over said network, at said times, images corresponding to a greater, and respectively smaller, quantity of information than the average of the images. During the determining step, a period of cyclical variation of the quantity of information that may be sent over the network is determined.
Abstract:
To predict the transmission error rate in a stream of data packets transmitted between a server and at least one client in a communication network: the server sends at least one group of packets to the client; the client calculates a plurality of items of statistical information on the group of packets and transmits them to the server; the server analyzes the items of statistical information so as to obtain a network stability indicator; and the server calculates a prediction of the transmission error rate on the basis of the network stability indicator.
Abstract:
The present invention discloses a method of displaying a sequence for sharing digital data items with a set of recipients using a terminal capable of using at least two communication modes for communicating with the recipients. The method comprises the steps of obtaining a first list of recipients communicating with the terminal according to a first communication mode, obtaining at least one second list of recipients communicating with the terminal according to a second communication mode, displaying on the mobile terminal a representation of each recipient in the lists thus obtained, selecting at least one representation, determining the communication mode to be used according to the representation selected and sending data item to the recipient whose representation was selected according to the determined communication mode. The invention also describes a sharing device adapted to implement the method, in particular a digital camera.
Abstract:
A digital document system in which a digital document in a communication network is shared between a plurality of stations, said system comprising: a first station (101A) having a first digital document (DD1) comprising a thumbnail data item (TH1) and an original data item (HR1); a second station (102A) having a second digital document (DD2) comprising a thumbnail data item (TH2); and a center station (100A) comprising: calculating means for calculating signatures of the thumbnail data items (TH1, TH2) of the first and second digital documents (DD1, DD2); comparing means for comparing the calculated signatures of the thumbnail data items (TH1, TH2); and transmitting means for transmitting information for accessing the original data item (HR1) of the first digital document (DD1) to the second station (102A) according to a result of the comparison.
Abstract:
The access method comprises the following steps: i) receiving a request coming from a user for accessing at least one digital document, said request comprising an identifier (303) designating the digital document and an identifier (304) designating said user; ii) searching locally for at least one collection (C1) containing the identifier (303) of the document and the identifier (304) of the user, each collection (C1, C2) being stored locally in response to a positive verification with regard to at least one condition agreeing to supply the document according to at least one access right linked to the collection; and iii) in the case of a positive search, supplying said corresponding document (303) to said user (304) thus designated.