Video subsystem for computer-based conferencing system

• US 5,490,247 A
• Filed: 11/24/1993
• Issued: 02/06/1996
• Est. Priority Date: 11/24/1993
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Gutmann, Mike, Tung, Peter
• Primary Examiner(s): Bayerl, Raymond J.
• Assistant Examiner(s): Tung, Kee M.
• Application Number:
  US08/157,478
• Time in Patent Office: 804 Days
• Field of Search: 395/162-164, 395/114, 395/200, 395/200.04, 370/62, 379/202, 348/15, 348/384, 382/56, 382/232, 364/514 A, 364/514 C
• US Class Current: 345/501
• CPC Class Codes: H04L 12/1813 for computer conferences, e.g. chat rooms instant messaging H04L51/04; protocols for multimedia communication H04L65/1101; arrangements for multi-party communication H04L65/403; telephonic conference arrangements H04M3/56; television conference systems H04N7/15
• CPC Class Codes: H04M 2201/22 Synchronisation circuits
• CPC Class Codes: H04M 3/567 Multimedia conference systems
• CPC Class Codes: H04N 21/4143 embedded in a Personal Computer [PC]
• CPC Class Codes: H04N 7/15 Conference systems
• CPC Class Codes: H04Q 11/0428 Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals

Abstract

A video microcode resides on a video board of the computer conferencing system. A video capture driver, a video manager, and a video applications programming interface reside on a general-purpose host processor of the computer conferencing system. The video microcode receives local analog video signals, generates local compressed video signals corresponding to the local analog video signals, and passes the local compressed video signals to the video capture driver. The video capture driver controls the operations of the video microcode and passes the local compressed video signals to the video manager. The video manager passes the local compressed video signals to a communications subsystem of the computer conferencing system for transmission over a communications link to a remote computer conferencing system. The video manager receives remote compressed video signals from the communications subsystem and passes the compressed video signals to the video capture driver, the communications subsystem having received the remote compressed video signals over the communications link from the remote computer conferencing system. The video capture driver generates remote decompressed video signals corresponding to the remote compressed video signal for local playback.

Claims

1. A video subsystem for a computer conferencing system having a general-purpose host processor, comprising:

(a) a video capture means for;

(1) receiving local video signals;

(2) compressing the local video signals to generate local compressed video signals; and

(3) passing the local compressed video signals to a communications subsystem of the computer conferencing system for transmission over a communications link to a remote computer conferencing system; and

(b) a video playback means for;

(1) receiving remote compressed video signals from the communications subsystem, the remote compressed video signals having been transmitted by the remote computer conferencing system over the communications link; and

(2) decompressing the remote compressed video signals to generate remote decompressed video signals for local playback, wherein the decompression of the remote compressed video signals is implemented on the general-purpose host processor, wherein the video subsystem comprises a video manager adapted for residing in the general-purpose host processor and for controlling operations of the video subsystem, for passing the local compressed video signals to the communications subsystem, and for receiving the remote compressed video signals from the communications subsystem, wherein the video manager comprises;

(1) a library component adapted to provide a library of functions of the video applications programming interface;

(2) a capture component adapted to control the capture of the local video signal by the video board and distribution of the local compressed video signals from the video board;

(3) a playback component adapted to control the decompression and playback of the remote compressed video signals;

(4) a network library component adapted to provide interfaces to send the local compressed video signals to the communications subsystem and to receive the remote compressed video signals from the communications subsystem; and

(5) an audio-video synchronization library component adapted to provide interfaces to enable synchronization of the local and remote video signals with local and remote audio signals in the computer conferencing system.

2. The video subsystem of claim 1, further comprising:

a video microcode adapted for residing in a video board of the computer conferencing system and for compressing the local video signals;

a video capture driver adapted for residing in the general-purpose host processor and for controlling operations of the video board; and

a video applications programming interface adapted for residing in the general-purpose host processor and for providing an interface between an application and the video subsystem.

3. The video subsystem of claim 2, wherein the video board comprises:

a video capture module for capturing the local video signals;

a memory device for storing the local captured video signals; and

a pixel processor for executing the video microcode and for compressing the local captured video signals.

4. A computer conferencing system, comprising:

(a) a general-purpose host processor;

(b) a video board; and

(c) a video subsystem adapted for residing partially in the general-purpose host processor and partially in the video board, wherein the video subsystem comprises;

(1) a video capture means for;

(i) receiving local video signals;

(ii) compressing the local video signals to generate local compressed video signals; and

(iii) passing the local compressed video signals to a communications subsystem of the computer conferencing system for transmission over a communications link to a remote computer conferencing system; and

(2) a video playback means for;

(i) receiving remote compressed video signals from the communications subsystem, the remote compressed video signals having been transmitted by the remote computer conferencing system over the communications link; and

(ii) decompressing the remote compressed video signals to generate remote decompressed video signals for local playback, wherein the decompression of the remote compressed video signals is implemented on the general-purpose host processor, wherein the video subsystem comprises a video manager adapted for residing in the general-purpose host processor and for controlling operations of the video subsystem, for passing the local compressed video signals to the communications subsystem, and for receiving the remote compressed video signals from the communications subsystem, wherein the video manager comprises;

(1) a library component adapted to provide a library of functions of the video applications programming interface;

(2) a capture component adapted to control the capture of the local video signal by the video board and distribution of the local compressed video signals from the video board;

(3) a playback component adapted to control the decompression and playback of the remote compressed video signals;

(4) a network library component adapted to provide interfaces to send the local compressed video signals to the communications subsystem and to receive the remote compressed video signals from the communications subsystem; and

(5) an audio-video synchronization library component adapted to provide interfaces to enable synchronization of the local and remote video signals with local and remote audio signals in the computer conferencing system.

5. The system of claim 4, wherein the video subsystem further comprises:

a video microcode adapted for residing in the video board and for compressing the local video signals;

a video capture driver adapted for residing in the general-purpose host processor and for controlling operations of the video board; and

a video applications programming interface adapted for residing in the general-purpose host processor and for providing an interface between an application and the video subsystem.

6. The system of claim 5, wherein the video board comprises:

a video capture module for capturing the local video signals;

a memory device for storing the local captured video signals; and

a pixel processor for executing the video microcode and for compressing the local captured video signals.