US 5,477,542 A · Method and appartus for controlling multimedia information communication

Abstract

A system in which multimedia information communication is performed between two terminal stations connected to each other through a packet switching network, each of the terminal stations having a control device for performing send control for sending a video packet including coded video data and a voice packet including coded voice data to the packet switching network and supply control for supplying the video packet and voice packet received from the packe switching network to a video codec and a voice codec respectively. One of the two terminal stations operating as a receive side issues a video data transmission mode change request to the other terminal station located at a multimedia information transmission side in accordance with a status of delay of video packets and/or voice packets received from the packet switching network, and the other of said terminal stations changes the video data transmission mode in response to the transmission mode change request, so that when the delay generated in the voice packet arrival interval exceeds a predetermined threshold value, video transmission is stopped and the operation mode is made to be a communication mode of only voice data.

Claims14

Dependent claims

A transmission control method in multimedia information communication performed between two terminal stations connected to each other through a packet switching network, each of said terminal stations having control means for performing transmission control for transmitting a video packet including coded video data and a voice packet including coded voice data to said packet switching network and for performing supply control for supplying said video packet and voice packet received from said packet switching network to a video codec and a voice codec respectively, said control method comprising the steps of:

one of said two terminal stations operating as a receiving side terminal station transmitting a video data transmission mode change request to the other terminal station operating as a multimedia information transmission side in accordance with a status of delay of video packets and/or voice packets received from said packet switching network;
and
said transmission side terminal station changing the video data transmission mode in response to said transmission mode change request.

A multimedia communication terminal station for performing multimedia communication with another terminal station through a packet switching network, comprising:

video data transmission control means for controlling transmission of a video packet including coded video data to said packet switching network;
video data reception control means for controlling supply of a video packet received from said packet switching network to a video decoding circuit;
voice data transmission control means for controlling transmission of a voice packet including coded voice data to said packet switching network;
and
voice data reception control means for controlling supply of a voice packet received from said packet switching network to a voice decoding circuit;
wherein said video reception control means includes:
first means for observing video packet delay time generated in said packet switching network, and
second means for issuing a video data transmission mode change request to another terminal station in accordance with the delay time of video packets observed by said first means;
and
wherein said video data transmission control means controls a video packet transmission interval in response to a video data transmission mode change request received from another terminal station.

7 more elements

Dependencies are inferred from the claim text.

Method and appartus for controlling multimedia information communication

Life of this patent

Method and appartus for controlling multimedia information communication

Life of this patent

Abstract

Claims14