Abstract: A method of communication between a first communicating entity and an application server, includes establishing a first sequence of exchanges of candidates; generating a first transmission channel establishing a first application session; detecting by a first communicating entity a new access network including a second gateway, resulting in the establishment of a second sequence of exchanges of new candidates; automatic configuring the configurable gateway so as to modify the correspondence between the source address of the second NAT gateway with the peer reflexive address of the NAT gateway which is configurable from the history of the candidates sent by the communicating entity; generating a second transmission channel maintaining the first application session.

Abstract: A method of transmission by a surveillance device to a control room, via a telecommunications network, of a series of images, includes steps, implemented by the surveillance device, of acquisition of a series of images, of coding of the series of images acquired into a series of base video frames including a first quantity of information and into at least one series of enhancement video frames of the series of base video frames, the series of enhancement video frames including a second quantity of information making it possible to enhance the quality of the series of images coded into the series of base video frames, of transmission in real time via the telecommunications network of at least the series of base video frames to the control room, and of storage of at least the series of enhancement video frames.

Abstract: A method of communication between a first communicating entity and an application server, includes establishing a first sequence of exchanges of candidates; generating a first transmission channel establishing a first application session; detecting by a first communicating entity a new access network including a second gateway, resulting in the establishment of a second sequence of exchanges of new candidates; automatic configuring the configurable gateway so as to modify the correspondence between the source address of the second NAT gateway with the peer reflexive address of the NAT gateway which is configurable from the history of the candidates sent by the communicating entity; generating a second transmission channel maintaining the first application session.

Abstract: A communication method of a first device over a first radio communication link of a first communication network and a second device over a second radio communication link of a second communication network, includes a step of suspending, during a suspension time interval, transmission of a first signal by the first device over the first radio communication link; and a step of receiving, with the second device, a second signal over the second radio communication link during the suspension time interval.

Abstract: A method of transmission by a surveillance device to a control room, via a telecommunications network, of a series of images, includes steps, implemented by the surveillance device, of acquisition of a series of images, of coding of the series of images acquired into a series of base video frames including a first quantity of information and into at least one series of enhancement video frames of the series of base video frames, the series of enhancement video frames including a second quantity of information making it possible to enhance the quality of the series of images coded into the series of base video frames, of transmission in real time via the telecommunications network of at least the series of base video frames to the control room, and of storage of at least the series of enhancement video frames.

Abstract: A communication method of a first device over a first radio communication link of a first communication network and a second device over a second radio communication link of a second communication network, includes a step of suspending, during a suspension time interval, transmission of a first signal by the first device over the first radio communication link; and a step of receiving, with the second device, a second signal over the second radio communication link during the suspension time interval.

Abstract: Apparatus and methods for controlling the amount of data used to transmit still images during the transmission of a video sequence from a first to a second location are disclosed. The apparatus of one embodiment comprises encoding means (105) arrange for intraframe encoding still images for transmission and intraframe encoding part or all of selected video sequence frames, calculating means (106) for determining the data size of intraframe encoded video sequence frames and control means (107) for controlling intraframe encoding of still images for transmission in dependence on the determined intraframe encoded size of a previous video sequence frame. The system can be operated in a way so as to remain H.263 compliant. Other embodiments control the data size by adjusting the quantization used for each Macroblock and by reprocessing each Group of Blocks until a desired data size is reached.