Electronic program guide and text channel data controller

We claim:

1. A system for controlling the presentation of text data from a text service provider to a customer's television display, comprising:

a database for storing text data from a plurality of sources of text data;

means for formatting text data stored in said database and associated display commands into transactions having a predetermined number of bytes, and for assigning each of said sources of text data to a unique video program channel for transmission to said customer's television display;

means for inserting said transactions into predetermined intervals of the unique video program channel to which text data in said transactions is assigned; and

a text data receiver associated with said customer's television display which extracts said transactions from their unique video program channel and presents a screen of text data from said transactions to said customer's television display in accordance with said associated display commands in said transactions.

2. A system as in claim 1, wherein at least one of said sources of text data provides electronic program guide (EPG) data representing the video programs available for display on said customer's television display.

3. A system as in claim 1, wherein said sources of text data communicate with said database via a communications link.

4. A system as in claim 3, wherein said communications link comprises at least one of a satellite link and a modem link to said database.

5. A system as in claim 4, further comprising a data interface for providing common input ports for each of said sources of text data and for routing text data from each of said sources to said database.

6. A system as in claim 5, wherein said data interface operates in a simplex mode for transmissions from said satellite link and in a duplex mode for transmissions from said modem link.

7. A system as in claim 5, wherein said database is divided into a plurality of source databases, one source database for each source of text data.

8. A system as in claim 1, further comprising means for compressing data from said sources of text data prior to storage in said database.

9. A system as in claim 2, further comprising a database manager for authorizing access to said database, sorting received EPG data by assigned video program channel and time of day, and performing garbage collection on said database.

10. A system as in claim 7, wherein said formatting and assigning means assigns a source database to each new source of text data, controls said data interface to route text data from said new source to its source database, and updates access authorization to said source database for said new source of text data.

11. A system as in claim 1, wherein said predetermined intervals are vertical blanking intervals of the unique video program channel to which that text data is assigned and said inserting means inserts said transactions into said vertical blanking intervals of said unique video program channel.

12. A system as in claim 11, wherein said inserting means stores a number of transactions for creating a screen of text data on said television display and inserts said transactions into said vertical blanking intervals of said unique video program channel to which the source which produced the text data in said number of transactions is assigned.

13. A system as in claim 2, wherein said text data receiver comprises an EPG memory for storing EPG data representing the video programs available for display on said customer's television display over a predetermined interval of time.

14. A system as in claim 13, wherein said text data receiver further comprises a template memory for storing a video display template into which said EPG data is inserted for display on said customer's television display, said video display template representing a time grid for each authorized video programming channel in said EPG data which may be received by said customer's television display.

15. A system as in claim 14, wherein said text data receiver selectively accesses said EPG data in said EPG memory so as to allow said customer to scan through said EPG data.

16. A system as in claim 1, wherein said text data receiver comprises a text memory for storing at least a page of text data for presentation to said customer's television display.

17. A system as in claim 1, wherein said text data receiver comprises a bit map for correlating a designated channel on the customer's television display to a frequency which must be tuned to get the text data for the designated channel from a vertical blanking interval of the video program channel containing the text data for the designated channel.

18. A method of controlling presentation of text data from a text service provider to a customer's television display, comprising the steps of:

authorizing one of a plurality of sources of text data to access a source database for storage of text data from said one source;

transmitting said text data from said one source to said source database for storage;

assigning said text data from said one source to a unique video program channel;

reading said text data from said one source from said source database and formatting associated display commands and said text data stored in said source database into transactions having a predetermined number of bytes;

inserting each transaction into a predetermined interval of the unique video program channel to which the text data in that transaction is assigned;

at a customer's text data receiver, extracting said transactions from their unique video program channel;

processing said transactions at said customer's text data receiver to extract said text data and said associated display commands; and

presenting a screen of said text data in said transactions processed in said processing step to said customer's television display in accordance with said associated display commands in said transactions.

19. A method as in claim 18, wherein said one source of text data authorized in said authorizing step for access to said source database provides electronic program guide (EPG) data representing the video programs available for display on said customer's television display.

20. A method as in claim 18, wherein said transmitting step includes the step of transmitting said text data to said source database via a communications link comprising at least one of a satellite link and a modem link to said source database.

21. A method as in claim 20, wherein said transmitting step includes the steps of receiving said text data at an interface device of said source database which comprises common input ports for each of said sources of text data and routing the received text data to said source database.

22. A method as in claim 21, wherein said transmitting step includes the further step of sending a command response message to said one source upon receipt of a command from said one source including said text data.

23. A method as in claim 18, comprising the further step of compressing said text data prior to storage in said source database.

24. A method as in claim 20, comprising the further steps of sorting received EPG data by video program channel and time of day.

25. A method as in claim 18, wherein said assigning step includes the steps of assigning said source database to said one source of text data, routing text data from said one source to said source database, and updating access authorization to said source database for said one source of text data.

26. A method as in claim 18, wherein said reading and formatting step comprises the steps of forming said transactions as display commands for a predetermined number of characters of said text data and of instructing said customer's text data receiver regarding where and how to display said text data in said transactions on said customer's television display.

27. A method as in claim 26, wherein said predetermined interval is a vertical blanking interval of the unique video program channel to which that text data is assigned and said inserting step includes the step of inserting said transactions into said vertical blanking interval of said unique video program channel.

28. A method as in claim 27, wherein said inserting step includes the further steps of storing a number of transactions for creating a screen of text data on said customer's television display and of inserting said transactions into said vertical blanking interval of said unique video program channel to which the source which produced the text data in said number of transactions is assigned.

29. A method as in claim 19, comprising the further step of storing EPG data in an EPG memory of said customer's text data receiver representing the video programs available for display on said customer's television display over a predetermined interval of time.

30. A method as in claim 29, comprising the further step of storing a video display template in a template memory of said customer's text data receiver for insertion of said EPG data for display, said template representing a time grid for each authorized video programming channel in said EPG data which may be received by said customer's television display.

31. A method as in claim 30, comprising the further step of scrolling through said EPG data stored in said EPG memory of said customer's text data receiver.

32. A method as in claim 18, comprising the further step of storing at least a page of text data in a text memory of said customer's text data receiver for presentation to said customer's television display.

33. A method as in claim 18, wherein said presenting step includes the steps of tuning said customer's text data receiver to a frequency of a video program channel containing in its vertical blanking interval the text data for a text channel designated by the customer and presenting said text data to said customer's television display when said customer selects said designated text channel.

34. A method as in claim 18, comprising the further step of delaying a predetermined amount of time after a page of text data has been presented to said customer's television display before presenting a next page of text data to said customer's television display.

35. A data controller for controlling the presentation of text data received from a text service provider to a customer's television display associated with said data controller, wherein said text data is received from said text service provider as transactions which have been inserted into a vertical blanking interval of a video program channel to which the text data in said transactions has been assigned, each transaction comprising text data and associated display commands for controlling presentation of text data in said transaction to said customer's television display, said data controller comprising:

a tuner for tuning said customer's television display to said video program channel; and

a processor which extracts said transactions from said vertical blanking interval of said video program channel and maps the text data received in said transactions to a text channel of the customer's television display for presentation of a screen of said text data on said text channel in accordance with the display commands received in said transactions.

36. A data controller as in claim 35, further comprising an EPG memory for storing EPG data representing the video programs available for display on said customer's television display over a predetermined interval of time.

37. A data controller as in claim 36, further comprising a template memory for storing a video display template into which said EPG data is inserted for display on said customer's television display, said video display template representing a time grid for each authorized video programming channel in said EPG data which may be received by said customer's television display.

38. A data controller as in claim 36, wherein said processor selectively accesses said EPG data in said EPG memory so as to allow said customer to scan through said EPG data.

39. A data controller as in claim 35, further comprising a text memory for storing at least a page of text data for presentation to said customer's television display.

40. A data controller as in claim 39, wherein said processor selectively accesses text data in said text memory so as to allow said customer to scroll through said text data.

41. A data controller as in claim 35, wherein said processor comprises a bit map for correlating said text channel on the customer's television display to a frequency which must be tuned by said tuner to get the text data for the text channel from a vertical blanking interval of the video program channel containing the text data for the text channel.

Description Submit all comments and votes

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a data controller which manages the flow of text and electronic program guide data from the data supplier to the viewer's television tuner. In particular, the data controller of the invention accepts electronic program guide and text data from one or more local or remote sources, processes the data in its internal database manager, and formats the data for transmission to the viewer's television tuner preferably via the vertical blanking intervals of existing cable television channels.

2. Description of the Prior Art

Television text data services are readily available. Such services provide sports, weather, stock market, news, advertising and other information to the viewer's television for display to the viewer. Typically, the text data is provided to the cable head end by the text data service providers and then provided to the viewer via dedicated cable channels provided at the cable head end. At the cable head end, the text data from the different text data service providers is assigned to respective cable television channels available to the viewers, converted into a video signal, and then transmitted to the viewer's television via the assigned cable television channel in place of other programming. The viewer then tunes to the assigned cable television channel to receive the transmitted text data. Unfortunately, this technique wastes valuable video bandwidth for the transmission of the text data and is thus generally undesirable. Also, since the cable head end operator must create a video signal from the text data provided by the service providers prior to transmission of the text data to the viewer, the existing technique for providing text data to a viewer is quite tedious and expensive. A more efficient text data service is desired.

Other techniques for providing text data to viewers are known in the art. For example, closed captioned encoding techniques are used to transmit text data in synchronization with its associated video data by inserting the closed captioned text data into the vertical blanking interval of the video signal. In this manner, not only can synchronization be preserved, but also, additional bandwidth is not necessary for the transmission of the text data. However, the closed captioned text data must be inserted into the vertical blanking interval of the video signal by the producer of the video programming. As a result, the vertical blanking interval of the video signal cannot be used by the head end operator to insert other text data such as sports, weather, stock market, news, advertising and the like. An improved text data transmission technique is desired whereby such general text data may be inserted into the video signal at the cable head end for transmission to the viewer.

It is also known in the art to provide an electronic program guide (EPG) which provides the viewer with an on-screen listing of the upcoming television programs on the cable television channels available to the viewer. Typically, the EPG is provided by an EPG data service and the EPG data is converted into a video signal at the cable head end and transmitted to the viewer's television via a dedicated cable television channel. After tuning to the dedicated cable television channel, the viewer then must passively wait until the programming for the desired time period is displayed. In other words, this technique provides no mechanism for allowing the viewer to scroll through the EPG to the desired listing. Moreover, this technique also requires the cable head end operator to dedicate a separate cable television channel to the EPG data and to create video signals from the EPG data provided by the EPG service providers.

These problems with the transmission of EPG data have been addressed in the prior art by modulating the EPG data onto an FM carrier and transmitting that FM carrier with a video signal on one of the cable television channels. A dedicated peripheral device provided at the viewer's television tuner demodulates the EPG data from the FM carrier and stores the EPG data until the viewer requests presentation of the EPG data on the viewer's television. Upon selection of the EPG data, the EPG is displayed on the viewer's television in place of the other video programming. Since the EPG data is stored locally at the viewer's television, the viewer may scroll through the listings in the EPG until the desired listing is reached. While this technique does not require a separate dedicated cable television channel for the transmission of the EPG and allows the user to scroll through the EPG, an improved EPG transmission technique is desired which can be integrated with the viewer's normal cable television tuner so that a separate peripheral device dedicated to reception of the EPG is not necessary. Also, it is desired that the EPG data transmission be combined with the text data transmission to maximize efficiency.

In addition, it is also known to amplitude modulate the audio carrier or to frequency modulate an out-of-band carrier with control and authorization information from the head end controller for transmission to the viewers' cable television tuners. However, it is desired that the transmission of the control and authorization information also be integrated with the text data and EPG data transmission so that a single common data transmission/reception scheme may be used.

The present invention has been designed to meet these needs in the art.

SUMMARY OF THE INVENTION

The present invention relates to a data controller which manages the flow of text data and electronic program guide (EPG) data to a cable television viewer. The data controller of the invention receives text data and EPG data from one or a plurality of local or remote data sources via a communications link, processes the received data in its internal database manager to perform data compression and the like, and then provides this text data and EPG data to the viewer under control of the head end controller. In a preferred embodiment, the text data and EPG data are inserted into the vertical blanking intervals of cable television channels to which the corresponding text data or EPG data has been assigned, and upon receipt at the viewer's television tuner, the text data and EPG data are extracted from the vertical blanking interval and displayed on the viewer's television. Hence, text channels and one or more EPG channels may be provided as "virtual channels" which do not require extra video bandwidth.

Preferably, the viewer's cable television tuner includes an EPG memory for storing the EPG data at the viewer's television tuner to allow the viewer to scroll through the stored EPG data to the desired listings. Also, a template memory is preferably provided at the tuner to provide a framework in which to display the EPG data. Also, the EPG data is formatted into transactions including display commands and the like so that the EPG data may be transmitted directly to the viewer's television tuner as data rather than video, thereby saving a substantial amount of bandwidth.

In addition, the text data is also formatted into transactions including display commands and the like and transmitted to the viewer's television tuner on a screen by screen basis with an appropriate delay between the presentation of each page as designated by the system controller. Such auto-pagination makes it unnecessary for the user to request the pages to scroll; however, manual pagination may be provided by using memory at the set top tuner for storing successive pages of text data.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the invention will become more apparent and more readily appreciated from the following detailed description of the presently preferred exemplary embodiment of the invention taken in conjunction with the accompanying drawings, of which:

FIG. 1 is a block diagram of a system for providing EPG data and text data to a viewer in accordance with the invention.

FIG. 2 illustrates a data controller for receiving the EPG data and text data from the data providers, appropriately formatting that data for display, and inserting the data into the vertical blanking interval of a cable television channel to which the data is assigned for transmission to the viewer.

FIG. 3 illustrates the information field of the EPG data read from the EPG database of FIG. 2.

FIG. 4 illustrates the data format of data read from the database for insertion into the assigned cable television channel.

FIG. 5 is a flow chart illustrating the operation of the EPG transaction formatter of FIG. 2.

FIG. 6 is a flow chart illustrating the operation of the text transaction formatters of FIG. 2.

FIG. 7 illustrates a set top tuner for use in receiving text data and EPG data in accordance with the invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENT

An electronic program guide (EPG) and text channel data controller which affords the above-mentioned and other beneficial features in accordance with a presently preferred exemplary embodiment of the invention will be described below with reference to FIGS. 1-7. Those skilled in the art will readily appreciate that the description given herein with respect to those figures is for explanatory purposes only and is not intended in any way to limit the scope of the invention. For example, while a cable television system is shown and described, the present invention may also be used in a satellite, over-the-air broadcast, subscription television system or other television system known in the art. Also, while the present invention is described for use in the provision of sports and weather text channels, those skilled in the art will appreciate that these text channels are only examples of the limitless types of text channels which may be provided to a viewer in accordance with the invention. Accordingly, any questions regarding the scope of the invention should be resolved by referring to the appended claims.

FIG. 1 illustrates an EPG and text information service in accordance with the invention. As shown, the local cable television company's billing vendor 10 communicates via a billing link to an RS-232 port of a system manager 12 located at the cable head end. Billing vendor 10 includes a subscriber database and generates a monthly bill for the subscribers in the system based on the level of service and any pay-per-view purchases. Billing vendor 10 may comprise a personal computer or other data processing device known in the art. Billing vendor 10 informs system manager 12 as to which cable television subscribers are authorized to receive the available cable television channels. System manager 12 is also a personal computer or other processing device which receives viewer authorization transactions from billing vendor 10 and generates transactions for delivery to the distribution apparatus or the subscribers. Such transactions include text channel definition transactions which instruct the subscriber's tuner which group of channels it is entitled to receive, which frequency to tune for a particular text data channel, whether to mute the audio for that text channel, the pagination delay between pages, and the like.

System manager 12 also communicates via a head end link to an RS-232 port of a head end controller (HEC) 14 which controls the transmission of television programming to the subscribers. As will be described in more detail with respect to FIG. 2, HEC 14 communicates via a control link to an RS-232 port of an information services processor (or data controller) 16 which manages the flow of EPG and text data in accordance with the invention. As shown by dotted line in FIG. 1, information services processor (ISP) 16 is preferably located at the cable head end with system manager 12, HEC 14 and the signal scramblers. However, those skilled in the art will appreciate that all of the head end equipment need not be located at one site.

As shown in FIG. 1, EPG data is supplied from one or more local or remote EPG suppliers 18 via a satellite link, modem link or other communication link to an RS-232 port of ISP 16. Similarly, text data from one or more text channel suppliers 20 is provided via a satellite link, modem link, or other communication link to another RS-232 port of ISP 16. In preferred embodiments, ISP 16 has a plurality of identical RS-232 ports for accepting data from a plurality of EPG suppliers 18 and text channel suppliers 20. Also, as shown, one of these RS-232 ports is preferably used for a control link to HEC 14 as well. As will be described in more detail below with respect to FIG. 2, ISP 16 manages EPG and text source databases in response to control signals from HEC 14 in order to provide EPG data and/or text channel data to selected viewers.

As shown in FIG. 1, HEC 14 also provides control data directly to the viewer's television tuner via an RS-485 output port. Preferably, the control data from HEC 14 includes the aforementioned text channel definition transactions as well as EPG definition transactions for instructing the tuner at which frequency to tune for the EPG data and the like. The control data may also include software for downloading into the viewer's tuner for reprogramming the viewer's tuner as necessary. In a preferred embodiment, the control data from HEC 14 is inserted into the vertical blanking interval of the selected cable television signal by daisy-chained scramblers 22, 24 and 26 using known in-band techniques, although the control data from HEC 14 may also be modulated on an out-of-band carrier or an in-band audio carrier for transmission as described in related U.S. patent application Ser. No. 07/983,766, filed Dec. 1, 1992 and assigned to the present assignee, the contents of which are hereby incorporated by reference. Preferably, scramblers 22-26 are daisy-chained so that the scramblers may be addressed individually or globally.

Similarly, EPG data and text channel data from ISP 16 are provided to the viewer's television tuner via an RS-485 output port of ISP 16. EPG data and text channel data are similarly inserted into the vertical blanking intervals of selected cable television signals by EPG scrambler 28 and text channel scramblers 30 and 32, respectively, using, for example, the in-band vertical blanking interval insertion techniques described in the aforementioned patent application Ser. No. 07/983,766 filed Dec. 1, 1992. Of course, if desired, scramblers 22-32 may insert the control data, EPG data, and text channel data into other portions of the video signals such as the horizontal blanking intervals or else replace the video entirely. Those skilled in the art will also appreciate that a number of scramblers may be provided in accordance with the volume of data received from HEC 14 and ISP 16. Typically, however, the number of scramblers depends on the number of premium channels for which scrambling is used.

Preferably, EPG scrambler 28 and text channel scramblers 30 and 32 are identical to control data scramblers 22-26 and are similarly daisy-chained for individual or global addressing. As shown in FIG. 1, scramblers 28-32 receive a single serial data channel which carries the combined EPG data and text data and display control transactions (to be described in more detail with respect to FIG. 2) for all data streams in use. Each scrambler is also equipped with memory for storing a predetermined amount of this data in an internal memory so as to minimize the number of database accesses. Preferably, scramblers 28-32 have internal memory sufficient to store a significant number of transactions. For example, scrambler 30 may have enough internal memory to score a day's sports scores for display on a sports text channel. The data received and stored in scramblers 28-32 is preferably in RS-485 format, and the protocol in a preferred embodiment is SDLC. All data transactions to scramblers 28-32 are sent on individual data streams specifying the target scrambler (station addresses in SDLC protocol), and the control data is sent on a global data stream which is filtered in the scramblers 28-32 based on the address of the scrambler so that the data streams can be configured by a transaction from ISP 16. The individual EPG data and text data streams are preferably generic in the scramblers so that they can be allocated as desired. Preferably, scramblers 28-32 have baud rates of at least 9600.

Preferably, the subscriber's tuner is a set top tuner 34 which comprises an EPG memory 36 for storing the EPG data from ISP 16. For example, EPG memory 36 may store one or two weeks of EPG data for selective access by the viewer via a menu of the set top tuner 34. This menu preferably allows the viewer to scroll through the EPG data stored in EPG memory 36 using the key pads of the viewer's television remote control device. Set top tuner 34 may also comprise a nonvolatile template memory 38 for storing the template in which the EPG data is to be inserted for display to the viewer on the viewer's television 40. In this manner, a video signal containing the template display data need not be continuously retransmitted to the set top tuner 34, thereby saving more bandwidth. Instead, the EPG data only needs to be updated every 30 minutes or when there is a program change. Of course, different set top tuners 34 may have varied amounts of memory and processing capabilities for such purposes in accordance with the acceptable memory costs during manufacture of the set top tuner 34.

As shown in FIG. 1, set top tuner 34 may also comprise a text data memory 42 for storing a page of text data for presentation to the screen. Thus, while one page of text data is displayed to the subscriber, the next page of text data may be loaded into the text data memory 42.

As noted above, ISP 16 of the invention manages the flow of text data and EPG data from the data service provider to the viewer's set top tuner 34. ISP 16 manages this data by accepting data only from one or more authorized text data and/or EPG data sources, processing the text data and EPG data in its internal database manager, and formatting the processed data into a common data transaction format for output to the scramblers for transmission to the set top tuner 34. Provision of EPG data and text data to the subscribers is controlled by the head end controller 14 via the control link as will be described in more detail below.

In a preferred embodiment, ISP 16 comprises an IBM PS2 model 7546 personal computer having a plurality of RS-232 serial input ports for EPG data and/or text data inputs and at least one RS-485 HDLC serial link at its output of the type used by HEC 14. As shown in FIG. 1, the control link will be a single RS-232 serial port. The hardware and software components of ISP 16 are then configured as illustrated in FIG. 2.

As shown in FIG. 2, ISP 16 preferably comprises a plurality of RS-232 ports which provide a common interface for the EPG data and text channel data asynchronously provided by the EPG supplier(s) 18 and text channel suppliers 20. The EPG data and text channel data is transmitted to ISP 16 via a satellite link (when the interface is operated in simplex mode) or by modem (when the interface is operated in half duplex mode). Preferably, the data is transmitted at a baud rate of at least 1200.

ISP 16 functions as a "gate keeper" which only allows access by authorized data sources. Accordingly, when ISP 16 receives a message from an EPG supplier 18 or a text channel supplier 20, it first checks the data for authorization. If that supplier is not authorized, the data is ignored. On the other hand, if the supplier is authorized to access ISP 16, ISP 16 performs the requested action and returns a command response message. If the communications link is simplex, the response is ignored. Hence, access to ISP 16 is limited by authorization codes, but as will be described below, access is also limited by whether the data provider provides the EPG data or text data in the transmission protocol expected by ISP 16.

In particular, messages sent between an EPG supplier 18 or a text channel supplier 20 and ISP 16 are preferably formatted to include a start of text byte, a data block of ASCII characters, checksum bytes and an ASCII