PC-based conferencing system

Claim 1

A conferencing system for a personal computer having a general-purpose host processor, comprising: (a) a first computer plug-in board; (b) a second computer plug-in board; (c) a video subsystem adapted for residing partially in the host processor and partially in one of the first and second computer plug-in boards; (d) an audio subsystem adapted for residing partially in the host processor and partially in one of the first and second computer plug-in boards; and (e) a communications subsystem adapted for residing partially in the host processor and partially in one of the first and second computer plug-in boards, wherein: the video subsystem is adapted to: (1) receive local video signals; (2) compress the local video signals to generate local compressed video signals; (3) pass the local compressed video signals to the communications subsystem; and (4) display the local video signals in a first window on a digital computer monitor; the audio subsystem is adapted to: (1) receive local audio signals; (2) compress the local audio signals to generate local compressed audio signals; and (3) pass the local compressed audio signals to the communications subsystem; the communications subsystem is adapted to: (1) transmit the local compressed video signals and the local compressed audio signals over a communications link to a remote computer system; (2) receive remote compressed video signals and remote compressed audio signals over the communications link from the remote computer system; (3) pass the remote compressed video signals to the video subsystem; and (4) pass the remote compressed audio signals to the audio subsystem; the video subsystem is further adapted to decompress the remote compressed video signals to generate remote decompressed video signals for local playback; the video subsystem is further adapted to display the remote decompressed video signals in a second window on the digital computer monitor simultaneously with the display of the local video signals in the first window; the audio subsystem is further adapted to decompress the remote compressed audio signals to generate remote decompressed audio signals for local playback, wherein portions of the video, audio, and communications subsystem that reside on the host processor operate under a window-based operating system running on the host processor; the first computer plug-in board is a video board; the second computer plug-in board is a combined audio and communications board; the video subsystem is adapted for residing partially in the video board; the audio subsystem is adapted for residing partially in the audio and communications board; the communications subsystem is adapted for residing partially in the audio and communications board; the video subsystem comprises: (1) a video microcode adapted for residing in the video board and for compressing video signals; (2) a video capture driver adapted for residing in the host processor and for controlling the compression of video signals by the video microcode; (3) a video manager adapted for residing in the host processor and for controlling the operations of the video subsystem; and (4) a video application programming interface adapted for residing in the host processor and for providing an interface between an application adapted for residing in the host processor and the video manager; the audio subsystem comprises: (1) an audio task adapted for residing in the audio and communications board and for compressing and decompressing audio signals; (2) an audio manager adapted for residing in the host processor and for controlling the operations of the audio subsystem; and (3) an audio application programming interface adapted for residing in the host processor and for providing an interface between the application and the audio manager; and the communications subsystem comprises: (1) a communications task adapted for residing in the audio and communications board and for transmitting and receiving digitized signals over the communications link; (2) a communications manager adapted for residing in the host processor and for controlling the operations of the communications subsystem; and (3) a communications application programming interface adapted for residing in the host processor and for providing an interface between the application and the communications manager.