Video/audio information transmission system

• US 4,734,765 A
• Filed: 12/01/1978
• Issued: 03/29/1988
• Est. Priority Date: 12/02/1977
• Status: Expired due to Term

• Current Assignee: Nippon Telegraph and Telephone Corporation
• Original Assignee: Hitachi, Ltd., Nippon Telegraph and Telephone Corporation
• Inventors: Shibata, Yoji, Matsuhashi, Shoichi, Kosuge, Wataru, Okada, Shigetoshi
• Primary Examiner(s): ORSINO JR, JOSEPH
• Application Number:
  US05/965,704
• Time in Patent Office: 3,406 Days
• Field of Search: 358/93, 358/102, 358/903, 364/200, 364/900, 340/706, 340/717, 340/721, 340/745, 340/152 R
• US Class Current: 348/107
• CPC Class Codes: H04M 11/085 using a television receiver, e.g. viewdata system
• CPC Class Codes: H04N 1/00095 Systems or arrangements for the transmission of the picture signal
• CPC Class Codes: H04N 1/2179 Interfaces allowing access to a plurality of users, e.g. connection to electronic image libraries

Abstract

A center-to-end type information service system utilizing the public telephone networks that are fundamental communication media of nation-wide scale is disclosed in which desired information is requested from the terminal side to the center by means of a telephone set or simplified keyboard and then delivered to and received by a TV receiver. A part of the center functions is transferred together with the exchange function to a subcenter located near the terminal. Thus, the length of transmission path connecting the center to terminals becomes shorter and the cost of the whole system can be cut down. A simplified character generator is provided in the subcenter, thereby diminishing traffic of the video network.

Claims

1. A video/audio information service system comprising:

a center including therein files in which video/audio information are recorded, the center being disposed at a first location;

a plurality of subcenters disposed at different second locations spaced from said first location between said center and a plurality of subscriber terminals, respective subscriber terminals being disposed at different third locations and associated with respective ones of said subcenters, the distance beween said subscriber terminals and said center being greater than the distance between said subscriber terminals and associated subcenter, each of said subcenters including therein a character generator means for generating character information for an input monitor means corresponding to character information inputted from said subscriber terminals, change-over switch means for changing over said video/audio information and said character information, said change-over switch means being coupled to said character generator means, a plurality of video/audio buffer memories coupled to said change-over switch means, exchange means coupled to said video/audio buffer memories for communicating with said associated subscriber terminals, video system means having a frame memory, a video change-over unit coupled to said frame memory, a video output unit coupled to said video change-over unit and said character generator means coupled to said video change-over unit, audio system means having an audio change-over unit, said audio buffer memory coupled to said audio change-over unit and an audio output unit coupled to said audio change-over unit, control system means having a multi-frequency receiver and a microcomputer coupled to said multi-frequency receiver, said audio buffer memory and said character generator means, and said exchange means having an exchanger coupled to said audio and video output units and end office units coupled to said exchanger,

first transmission path means for connecting said center and said subcenters respectively to transmit said video/audio information in an analog baseband signal form, said character generator means in each subcenter being provided for diminishing traffic of said first transmission path means between said center and subcenters; and

second transmission path means for connecting said subcenter and said subscriber terminals respectively to transmit said video/audio information and said character information in an analog baseband signal form.

2. A video/audio information service system according to claim 1, wherein the files in which video/audio information are recorded has a video information file and an audio information file, the audio information file includes a microfilm search unit, a microfiche search unit, a picture/character generator, a digital picture file unit, a random-access motion picture file unit and a scheduled-time motion picture file unit, and wherein the audio information file includes an audio response unit and a PARCOR type audio per picture file unit.

3. A video/audio information service system according to claim 1, wherein said second transmission path means directly connects said subcenter and said subscriber terminals.

4. A video/audio information service system according to claim 1, wherein said first and second transmission path means include public telephone networks.

5. A video/audio information service system according to claim 1, wherein said character generator means generates character information for display on said input monitor means at said subscriber terminal in response to input information from said subscriber terminal for service connection, said first and second transmission path means including repeater means therein.

6. A video/audio information service system according to claim 1, wherein said subscriber terminal includes said input monitor means, said inut monitor means including a TV receiver, a converter coupled to said TV receiver for converting into an NTSC color TV signal, said signal transmitted in the analog baseband signal form, and terminal control means coupled to said associated subcenter.

7. A video/audio information service system according to claim 6, wherein said terminal controller means includes a push-phone.

8. A video/audio information service system according to claim 6, wherein said terminal controller means includes a keyboard.

9. A video/audio information service system comprising:

a center including a plurality of video and audio files, and a central processing unit for controlling the files;

a plurality of subscriber units, each subscriber unit including TV receiver means, converter means for converting an analog baseband signal into a standard TV signal for application to said receiver means, and terminal controller means for generating a calling signal and a request;

a plurality of subcenters each accommodating thereto a plurality of said subscriber units, each of said subcenters including therein a character generator means for generating character information for said TV receiver means corresponding to character information inputted from said subscriber units, change-over switch means for changing over said video/audio information and said character information, said change-over switch means being coupled to said character generator means, a plurality of video/audio buffer memories coupled to said change-over switch means, said exchange means coupled to said video/audio buffer memories for communicating with said associated subscriber units;

first transmission path means for connecting said center and said subcenter respectively to transmit said video/audio information in an analog based band signal form, said character generator means in each subcenter being provided for diminishing traffic of said first transmission path means between said center and subcenters; and

second transmission path means for connecting said subcenter and said subscriber units respectively to transmit said video/audio information and said character information in an analog baseband signal form, said central processing unit controlling said video and audio files in accordance with requests from said subscriber units via said subcenters, and

wherein said subcenter includes picture system means having a frame memory, a video change-over unit coupled to said frame memory, a video output unit coupled to said video change-over unit and said character generator means coupled to said video change-over unit, audio system means having an audio change-over unit, said audio buffer memory coupled to said audio change-over unit and an audio output unit coupled to said audio change-over unit, control system means having a multi-frequency receiver and a microcomputer coupled to said multi-frequency receiver, said audio buffer memory and said character generator means, and said exchange means having an exchanger coupled to said audio and video output units and end office units coupled to said exchanger.