US 5,375,068 A · Video teleconferencing for networked workstations

Abstract

A video teleconferencing method and apparatus for computer workstations connected by a digital data network includes a transmission source portion for a local workstation to send audio and video teleconference data across the network to one or more remote workstations, and, a receiver for the local workstation to receive audio and video teleconference data back from the remote workstations. The local workstation sends teleconference data to each of the remote workstations over a variable bandwidth digital data connection, and each of the remote workstations returns teleconference data back to the local workstation over another variable bandwidth digital data connection. The transmission source portion includes a master software process executing on the local workstation, and the receiver includes a slave software process executing the remote workstation. The master process of a local workstation causes execution of a slave process on a remote workstation for receiving video teleconference data from the local workstation. An audio data transmitter for sends an audio data stream to the remote workstation such that the audio data can be reconstructed into a continuous audio signal. A video transmitter sends video data so that each frame of video data to be sent is inserted into the audio data stream without affecting the continuity of the reconstructed audio signal at the remote workstation.

Claims46

Dependent claims

The video teleconferencing apparatus for a distributed data processing system having a plurality of computer workstations connected by a digital data network, the computer workstations comprising:

a) a master process executing on a processor of a local workstation formating and sending audio and video data across the digital data network as digital data packets to a remote workstation over a first variable bandwidth digital data connection;
b) a slave process executing on a processor of the remote workstation receiving and reconstructing the audio and video data from across the digital data network from the master process of the local workstation for audible and visual reproduction, respectively;
c) a master process executing on the processor of the remote workstation formatting and sending audio and video data across the digital data network as digital data packets to the local workstation over a second variable bandwidth digital data connection;
and
d) a slave process executing on the processor of the local workstation receiving the audio and video data from across the digital data network from the master process of the remote workstation for audible and visual reproduction, respectively;
wherein the master process of the local workstation causes the execution of the slave process on the remote workstation to receive the audio and video data sent by the master process of the local workstation, the slave process of the remote workstation causes the execution of the master process on the remote workstation to send the audio and video data to the local workstation, and the master process of the remote workstation causes execution of the slave process on the local workstation to receive the audio and video data sent by the master process of the remote workstation.

3 more elements

Video teleconferencing apparatus for a distributed data processing system having a plurality of computer workstations connected by a digital data network, the computer workstations comprising:

a) source means for a local workstation to send audio and video data across the digital data network as digital data packets to a remote workstation, the source means comprising a master process executing on a processor of the local workstation;
b) receiver means for the local workstation to receive audio and video data from across the digital data network as digital data packets sent from source means of the remote workstation, the receiver means comprising a slave process executing on a processor of the remote workstation;
wherein the master process of a local workstation causes execution of a slave process on a remote workstation for receiving audio and video data sent by the master process of the local workstation over one variable bandwidth digital data connection, the slave process on the remote workstation causes execution of a master process on the remote workstation for sending audio and video data to the local workstation, and the master process of the remote workstation causes execution of a slave process on the local workstation for receiving audio and video data sent by the master process of the remote workstation over another variable bandwidth digital data connection.

A video teleconferencing computer workstation comprising:

a video frame grabber for generating local video data by digitizing analog video signals received from a video source, and for accumulating said local video data to provide frames of said local video data;
a video buffer for receiving and temporarily storing said frames of local video data;
a network controller for transmitting said frames of local video data temporarily stored by said video buffer to a remote computer workstation via a first one-way variable bandwidth digital data connection providing a first virtual circuit connection across a digital data network;
a central processor for executing a local slave application program for configuring said video teleconferencing computer workstation to receive frames of remote video data generated by said remote computer workstation under control of a remote master application program controlling said local slave application program, said frames of said remote video data being transmitted via a second one-way variable bandwidth digital data connection providing a second virtual circuit connection across said digital data network, said central processor further executing a local master application program for establishing said first one-way variable bandwidth digital data connection to said remote computer workstation and invoking a corresponding remote slave application program in said remote computer workstation to configure said remote computer workstation to receive said frames of local video data transmitted by said network controller.

1 more element

A method for establishing and maintaining video teleconferencing link between a local computer workstation and a remote computer workstation, said method comprising:

executing a local master application program by said local computer workstation establishing a first one-way variable bandwidth digital data connection providing a first virtual circuit connection across a digital data network to said remote computer workstation;
and
invoking a corresponding remote slave application program by said local master application in said remote computer workstation to enable said remote computer workstation to receive frames of local video data generated by said local computer workstation;
executing a local slave application program in said local computer workstation by said remote computer workstation for configuring said local computer workstation to receive frames of remote video data generated by said remote computer workstation under control of a remote master application program controlling said local slave application program, said frames of remote video data being transmitted via a second one-way variable bandwidth digital data connection providing a second virtual circuit connection across said digital data network.

1 more element

Dependencies are inferred from the claim text.

Video teleconferencing for networked workstations

Life of this patent

Video teleconferencing for networked workstations

Life of this patent

Abstract

Claims46