Digital audio-video presentation display system

• US 5,119,188 A
• Filed: 09/04/1990
• Issued: 06/02/1992
• Est. Priority Date: 10/25/1988
• Status: Expired due to Term

• Current Assignee: TVWorks LLC (Comcast Corporation)
• Original Assignee: Telaction Corporation
• Inventors: Lodberg, Allan E., McNorgan, Richard, Wilson, Steven D., McCalley, Karl W., Fischer, James L.
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): Woo, Stella L.
• Application Number:
  US07/579,238
• Time in Patent Office: 637 Days
• Field of Search: 358/85, 358/86, 455/4, 455/5, 360/9.1
• US Class Current: 725/93
• CPC Class Codes: H04M 11/085 using a television receiver, e.g. viewdata system
• CPC Class Codes: H04N 1/2179 Interfaces allowing access to a plurality of users, e.g. connection to electronic image libraries
• CPC Class Codes: H04N 2007/1739 the upstream communication being transmitted via a separate link, e.g. telephone line
• CPC Class Codes: H04N 7/002 Special television systems not provided for by H04N7/007 - H04N7/18 still pictures via a television channel H04N1/00098
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests
• CPC Class Codes: H04N 7/17336 Handling of requests in head-ends

Abstract

An audio-video presentation display system based on manipulation of digitized information is disclosed for use in an interactive communications system wherein a subscriber may select for viewing on a television screen a plurality of audio-video presentations consisting of particular sequences of selected video frames and accompanying audio information. The audio-video presentation display system is responsive to commands from a host computer which designates and prepares the presentation for playback to the television of the subscriber who has requested it. The audio-video presentation display system includes a digital mass storage subsystem which provides for digital storage of compressed video and digitized audio information, and a plurality of digital audio-video display subsystems which include mechanisms for retrieving the selected digitized information from the storage subsystem, a subsystem for expanding and reformatting the data into a format suitable for television transmission, and another subsystem for controlling the transmission of the information to the subscriber who has requested it.

Claims

1. In an interactive communications system compatible with cable television systems wherein a subscriber may select for viewing on a television a plurality of audio video presentations consisting of particular sequences of selected video frames and possibly accompanying audio, a digital audio video presentation display system responsive to commands from a host computer which designates and prepares the presentation for playback to the television of the subscriber requesting the presentation comprising:

(a) a digital mass storage subsystem for storing compressed video and audio data objects in digital format; and

(b) at least one digital audio-video display subsystem which includes

(i) means for retrieving data objects corresponding to each of the selected video frames and accompanying audio information of the requested sequence in digital format from the digital mass storage subsystem upon command from the host computer;

(ii) means for expanding and reformatting the digital compressed video data into full frames of analog video compatible with television transmission and playback;

said means for expanding and reformatting said compressed video data including means for converting and sequencing said video and audio data objects into modulation compatible with said cable television systems

(iii) means for transforming the digital audio data into analog baseband audio and for modulating the baseband audio onto audio carrier frequencies compatible with television transmission and playback; and

(iv) means for controlling the transmission of the video frames and accompanying audio information in analog format to the headend of a cable network so that the subscriber requesting the information receives the information in the particular sequence designated by the host computer.

2. The digital audio-video presentation display system of claim 1 wherein the digital audio-video display subsystem further comprises means for encoding identifying information in the vertical blanking interval of the selected video frames.

3. The digital audio-video presentation display system of claim 2 wherein the digital audio-video display subsystem further comprises one or more display system controllers.

4. The digital audio-video presentation display system of claim 3 wherein the digital mass storage subsystem for storing and retrieving data objects of compressed video and audio data in digital format further comprises:

(a) a plurality of disc storage volumes, each disc storage volume including a disc drive, a disc drive controller, and a single board computer which serves as a disc storage volume manager that provides supervisory control of the disc storage volume;

(b) a plurality of chassis, each chassis housing at least one disc storage volume manager, at least one gateway module for importing and exporting data to and from the digital mass storage subsystem, at least one display system command module for connecting the digital mass storage subsystem to each of the display system controllers which comprise the digital audio video display subsystem, at least one object locator module for determining which disc storage volume is associated with a particular data object, and at least one interchassis communications module for interconnecting and transferring data to and from each of the plurality of chassis.

5. The digital audio video presentation system of claim 4 wherein the plurality of chassis include a central services module in each chassis for providing maintenance functions.

6. The digital mass storage subsystem of claim 4 wherein the disc storage volume managers, the gateway modules, the object locator modules, the display system command modules, and the interchassis communications modules each comprise a single board computer.

7. The digital mass storage subsystem of claim 4 wherein the interchassis communications modules which reside on one chassis are each connected in parallel to corresponding interchassis communications modules on the other chassis of the digital mass storage subsystem.

8. The digital mass storage subsystem of claim 4 wherein a display system command module is individually connected to a display system controller which comprises the digital audio video display subsystem.

9. The digital mass storage subsystem of claim 4 wherein a display system command module is interfaced in a redundant fashion to each of two display system controllers which comprise the digital audio-video display subsystem, and wherein each display system controller is interfaced to two display system command modules, each of which is on a separate chassis of the digital mass subsystem.

10. The digital audio video presentation display system of claim 1 wherein each digital audio video display subsystem further comprises:

(a) at least one digital video distribution unit which includes means for transforming compressed video data in digital format into full frames of video in RGB format;

(b) at least one digital audio distribution unit which includes means for which transforming digital audio data into baseband audio;

(c) at least one display system controller which includes means for coordinating the orderly transfer of data from the digital mass storage subsystem to the digital video distribution units and the digital audio distribution units;

(d) a plurality of audio transmitters which include means for receiving baseband audio signals from the digital audio distribution unit and for modulating these audio signals onto an audio subcarrier having a frequency appropriate for television transmission; and

(e) a scheduler control unit including means for accepting the RGB outputs from the digital video distribution units, and for converting the frame into a format compatible with television transmission and playback.

11. The digital audio video display subsystem of claim 10 wherein the scheduler control unit further comprises means for inserting identifying information into the vertical blanking interval of each frame.

12. The digital audio video display subsystem of claim 10 wherein the display system controller further comprises a single board computer for receiving presentation requests from the host computer and performing the scheduling of these requests, a plurality of interfaces for connection to the digital mass storage subsystem, a second plurality of interfaces for connection to the digital audio distribution unit, a third plurality of interfaces for connection to the digital video distribution unit, a plurality of single board computers for supervisory control for monitoring the loading of the display systems controller.

13. The digital audio video display subsystem of claim 10 wherein the digital video distribution unit further comprises a single board computer, an interface card, a floppy disc drive, a floppy disc drive controller and two digital video expander units for reading the compressed video data and producing expanded video frames in RGB format.

14. The digital audio video display subsystem of claim 10, wherein the digital audio distribution system further comprises a single board computer, a parallel interface card, a small computer system (SCSI) interface card, a floppy disc drive, a floppy disc drive controller, and a plurality of audio playback boards, each of which contains a digital signal processor, for converting the digital audio data into baseband audio.

15. The digital audio video display subsystem of claim 10 wherein the scheduler control unit further comprises an RGB switch, an encoder for converting RGB signals to a standard television transmission and playback format, and an address inserter for placing identifying information onto the vertical blanking interval of the video frame.

16. The address inserter of claim 15, wherein the identifying information comprises the address of the frame store unit to which the video frame will be sent and an audio receiver tuning code.