Abstract: A video and audio reproducing apparatus is provided with a re-synchronization controlling portion (20) for carrying out operation control with respect to re-synchronization of video and audio which are transmitted via an IP network, wherein the delay times of video data and audio data are controlled by the video delay controlling portion (21) and audio delay controlling portion (22), respectively, thereby carrying out re-synchronization. At this time, the re-synchronization controlling portion (20) judges re-synchronization timing on the basis of the audio level of audio data, encoding video type of video data, data transmission status and user operation, etc., and at the same time, judges the priority for which mode of the video priority mode or the audio priority mode the re-synchronization is carried out, on the basis of a fluctuation in the arrival time of audio data, data transmission status, contents of video data and audio data and user operation, etc.

Abstract: In a moving picture data structure having a structure comprising I pictures (intraframe coded image) and P pictures (interframe forward predictive coded image), a P? picture of a forward predictive coded image of a picture immediately preceding an I picture and the I picture is placed following the I picture. If an error occurs during the I picture transmission, the P? picture can be used to recover from the error.

Abstract: A system is arranged by a service providing apparatus 109 for storing a plurality of contents data 110 and capable of transmitting the contents data via network interfaces 116a/116b and a communication path 112; and also a service relaying apparatus 101 for producing compressed moving picture data having a high image quality from still picture data, and capable of transmitting the compressed moving picture data via network interfaces 115a/115b and another communication path 111 to a reproducing terminal 106. As a result, desirable contents data can be displayed by the reproducing terminal which owns a capability of displaying the compressed moving picture data, but does not own such a capability of displaying the desirable contents data.

Abstract: A method of presenting, at a client terminal, a video program stored in a server linked with the client terminal via transmission path of a limited transmission band width. Each frame of the video program comprises a basic data portion and at least one level of quality supplement data portions. In the method, in response to one of play control commands from a user, the client terminal determines a start position in the video program according to the issued play control command. The play control commands includes a play, a stop, a head search, a jump forward and a jump backward command. In response to the issued play command, the terminal obtains and uses the basic data portions for playing the video program. In response to the stop command, the terminal obtains the quality supplement data portions for the last displayed frame and uses them for displaying a quality-enhanced version of the last displayed frame.

Abstract: The invention provides a television meeting unit that is capable of displaying a picture smoothly on a middle participation terminal. To realize such television meeting unit, the multicast meeting unit is provided with a picture coding means for coding an input picture, a picture transmission means for transmitting the coded picture by mean of multicast, a picture receiving means for receiving the transmitted coded picture, a picture decoding means for decoding the received picture, a picture display means for displaying the decoded picture, a middle participation notice means for notifying middle participation in a meeting, and a middle participation terminal detection means for detecting the middle participation notice and for transmitting it to the picture coding means. The picture coding means, upon receiving the middle participation notice from the middle participation terminal detection means, changes the coding format to the in-frame coding format.

Abstract: A method of presenting, at a client terminal, a video program stored in a server linked with the client terminal via transmission path of a limited transmission band width. Each frame of the video program comprises a basic data portion and at least one level of quality supplement data portions. In the method, in response to one of play control commands from a user, the client terminal determines a start position in the video program according to the issued play control command. The play control commands includes a play, a stop, a head search, a jump forward and a jump backward command. In response to the issued play command, the terminal obtains and uses the basic data portions for playing the video program. In response to the stop command, the terminal obtains the quality supplement data portions for the last displayed frame and uses them for displaying a quality-enhanced version of the last displayed frame.

Abstract: The invention provides a television meeting unit that is capable of displaying a picture smoothly on a middle participation terminal. To realize such television meeting unit, the multicast meeting unit is provided with a picture coding means for coding an input picture, a picture transmission means for transmitting the coded picture by mean of multicast, a picture receiving means for receiving the transmitted coded picture, a picture decoding means for decoding the received picture, a picture display means for displaying the decoded picture, a middle participation notice means for notifying middle participation in a meeting, and a middle participation terminal detection means for detecting the middle participation notice and for transmitting it to the picture coding means. The picture coding means, upon receiving the middle participation notice from the middle participation terminal detection means, changes the coding format to the in-frame coding format.

Abstract: A video and audio reproducing apparatus is provided with a re-synchronization controlling portion (20) for carrying out operation control with respect to re-synchronization of video and audio which are transmitted via an IP network, wherein the delay times of video data and audio data are controlled by the video delay controlling portion (21) and audio delay controlling portion (22), respectively, thereby carrying out re-synchronization. At this time, the re-synchronization controlling portion (20) judges re-synchronization timing on the basis of the audio level of audio data, encoding video type of video data, data transmission status and user operation, etc., and at the same time, judges the priority for which mode of the video priority mode or the audio priority mode the re-synchronization is carried out, on the basis of a fluctuation in the arrival time of audio data, data transmission status, contents of video data and audio data and user operation, etc.

Abstract: Provided is a terminal unit that, even in case video image is suspended by a handover, video reproduction is possible real-time at immediately after an end of the handover. In a video transmission system comprising a wireless LAN accommodated switch for switching over the connection relationship of a terminal unit and an access point, an access point for receiving video data sent from a terminal unit and sending it to another terminal unit, and a terminal unit for receiving video data sent from the access point thereby displaying a video image and carrying out an association establishment or release of a wireless channel to an access point, the terminal unit operates such that, when a calling party releases a wireless channel, the opposite terminal unit determines that the calling party has started a handover and makes an operation to change a video data encoding into an intra-frame encoding.

Abstract: Provided is a server apparatus and terminal unit for realizing a video transmission system that, even in case the video image is suspended by a handover, reproduction can be resumed at a video image of upon suspension. In a video transmission system having a video server for sending video data to a terminal unit through an access point and a terminal unit for receiving and displaying the video data sent from the access point and for establishing an association and releasing of a wireless channel to the access point, the terminal unit releases the access point and wireless channel and requests the video server to suspend the transmission and store video data. In case an association is established with a new access point, the terminal unit requests the video server to re-send the video data, etc. stored in the duration of from the release to an association establishment.

Abstract: The invention provides a television meeting unit that is capable of displaying a picture smoothly on a middle participation terminal. To realize such television meeting unit, the multicast meeting unit is provided with a picture coding means for coding an input picture, a picture transmission means for transmitting the coded picture by mean of multicast, a picture receiving means for receiving the transmitted coded picture, a picture decoding means for decoding the received picture, a picture display means for displaying the decoded picture, a middle participation notice means for notifying middle participation in a meeting, and a middle participation terminal detection means for detecting the middle participation notice and for transmitting it to the picture coding means. The picture coding means, upon receiving the middle participation notice from the middle participation terminal detection means, changes the coding format to the in-frame coding format.

Abstract: In a moving picture data structure having a structure comprising I pictures (intraframe coded image) and P pictures (interframe forward predictive coded image), a P′ picture of a forward predictive coded image of a picture immediately preceding an I picture and the I picture is placed following the I picture. If an error occurs during the I picture transmission, the P′ picture can be used to recover from the error.

Abstract: In a moving picture data structure having a structure comprising I pictures (intraframe coded image) and P pictures (interframe forward predictive coded image), a P′ picture of a forward predictive coded image of a picture immediately preceding an I picture and the I picture is placed following the I picture. If an error occurs during the I picture transmission, the P′ picture can be used to recover from the error.

Abstract: The invention provides a television meeting unit that is capable of displaying a picture smoothly on a middle participation terminal. To realize such television meeting unit, the multicast meeting unit is provided with a picture coding means for coding an input picture, a picture transmission means for transmitting the coded picture by mean of multicast, a picture receiving means for receiving the transmitted coded picture, a picture decoding means for decoding the received picture, a picture display means for displaying the decoded picture, a middle participation notice means for notifying middle participation in a meeting, and a middle participation terminal detection means for detecting the middle participation notice and for transmitting it to the picture coding means. The picture coding means, upon receiving the middle participation notice from the middle participation terminal detection means, changes the coding format to the in-frame coding format.

Abstract: A conference terminal is incorporated in a multicast conferencing system. The conference terminal receives a request for division into groups. The request includes information indicating that the terminal belongs to which group. The terminal then produces, in response to the request, only the stream data coming from one or more other conference terminals belonging to the same group as the terminal. This production is realized by selectively accepting such stream data at a reception unit to which all stream data are transmitted from all the terminals having the same multicast address. Alternatively, the production is realized by selectively re-writing stream data at a scene re-writer. Thus, the produced stream data are replayed and displayed. The division of an entire group into plural small groups can be performed without additionally issuing multicast addresses.

Abstract: An information providing apparatus is realized: That is, in such a case that information is distributed/provided and this information is constituted by information formed by an information provider and also additional information such as an advertisement selected by the information provider, a use fee charged to the information provider can be reduced and/or increased based upon the additional information. Furthermore, since an information consumer refers to the additional information, a use fee charged to the information provider can be reduced and/or increased based on the additional information.

Abstract: A video transmitting apparatus having a plurality of transmission medium for transmitting multiplexed video information, a plurality of video information receiving units each connected to a corresponding transmission medium to receive specific video information on the corresponding transmission medium, a video displaying unit for displaying video information, a switcher for connecting the video displaying unit to any one of the video information receiving units to supply video information to the video displaying unit, and a video display requesting unit for communicating with each of the video information receiving units and the switcher to request to display specific video information on the video displaying unit by giving instructions to a relevant video information receiving unit which can receive the specific video information and the switcher.

Abstract: A picture transmission system capable of establishing arbitrary picture connections with picture inputting units exceeding in number channel resources of a transmission medium for multiplexing and transmitting video information taken through the picture inputting units. A picture sending state storage unit provided corresponding to each of the picture inputting units virtually retains channel resources whose number equals the number of picture outputting units to which the picture inputting units are in connection. For picture connection switching from one picture outputting unit to a different picture inputting unit, the picture sending state storage unit gives its channel resource to the different picture inputting unit. The system is provided with a picture connection managing unit for controlling the picture connections between the picture inputting units and the picture outputting units.

Abstract: A video monitor system comprises a transmitting medium, video cameras, monitors, VTR, monitor terminals, a control portion and a transmitting medium having channels of video signals and a data channel coupling these units. The video monitor receives a request of a desired camera and a desired monitor and supplies the data indicative the request. The control portion receives the data indicative of the request and determines one of channels and operates the desired camera and desired monitor thorough the determined one of channels to display a video signal on the desired monitor. The VTR records one of video signals from a desired video camera through determined one of channels. A priority is judged to control one video camera which are requested to be operated by two monitor control terminals at the same time. A diagnostic function for detecting a defect and a location in the transmitting medium and a sequential operation function are also provided.

Abstract: A bi-directional video signal transmission system is equipped with transmission lines having coupled upsteam and downstream segments. With the entire band of a RF signal being taken as a modulation frequency band, an image signal modulated to a frequency band and RF-multiplexed in the upstream segment is introduced into the downstream segment at the modulated frequency and is then branched to demodulate the same frequency band, thereby obtain one video signal transmission channel. In response to a request by a subscriber, a channel management section assigns and releases the transmission channels and further outputs a control command whereby a transceiver control section performs switching-control of the transmission frequencies to transceiver units.