FR2734975A1 - Teletext transmission method for TV receiver - Google Patents

Abstract

The method involves transmitting video signals via a television channel to a number of television receivers. Each receiver has a teletext receiver system. On transmission, a personalised code is selectively associated with at least one page of teletext data. This code acts as an address for identification of at least one of the television receivers. Pages of teletext data are simultaneously transmitted with the personal identification data. On reception, each receiver recognises the personal code by comparison with a television receiver identification code. Only pages intended for that television receiver are accepted and the transmitted information is stored and can be displayed.

Description

 The present invention relates to a teletext method allowing personalized addressing.

 It also relates to a system for implementing this method.

 First of all, it seems useful to briefly recall the characteristics of the teletext transmission mode.

 The basic principle of teletext or similar system is to transmit digital information of the text or semi-graphic type by the channel of the television signals, but during time intervals not occupied by the video signal (scan return intervals) .

 There are several standards, such as the CEEFAX standard, level I.

 This system makes it possible to transmit all the characters, upper and lower case, eight colors, as well as some attributes. The display is done in 40 columns on 24 lines.

 Many modern television receivers are provided with circuits for displaying the data transmitted by this process. They include in particular a specialized decoder and memory circuits recording teletext pages, all controlled by a microprocessor. These televisions usually have a remote control comprising specialized keys making it possible to have selective access to particular pages and / or information of a particular type (theme, etc.).

 We can point out two axes of evolution of this standard.

 The first evolution concerns an improvement of the graphics. According to the aforementioned standard, if one wishes to display drawings, the minimum pattern is a square with an area equal to the intersection of a line and a column. It has therefore been proposed to replace the colored squares with colored points or pixels.

 The second development aims to speed up the reading of teletext pages. Indeed, the aforementioned CEEFAX standard allows 1000 pages to be transmitted. It is therefore laborious to turn page after page to access information sought.

 Also two methods have been proposed: the methods known under the acronyms "TOP" (for "Top Of Page"), implemented in Germany in particular, and the method "FLOF", simpler, implemented in other countries Europeans such as Spain.

 These two methods allow easier and faster navigation among the teletext pages.

 From a hardware point of view, the TV remote control has additional buttons, more precisely four colored buttons: red, green, blue and yellow.

 The "TOP" system organizes the teletext pages according to a tree structure: blocks, pages, etc.

 For example, the red button addresses blocks associated with themes: sport, news, etc., and the green button for specific pages: national, international.

 In the "FLOF" system, there is an organization page after page: for example, from page 111 to 115, sports, etc. The red and green buttons play a role similar to that of a search button on a tape recorder (rear, front).

In summary, Teletext transmission, for example according to the standard
The above-mentioned CEEFAX enables teletext pages to be sent which are received by all television sets equipped with a teletext decoder.

When the latter have a memory, they can store the pages chosen by the consumer.

 The major drawback of this system is that it is not possible, for a given broadcaster, to predetermine on which televisions certain pages could be targeted.

 However, there are needs which make one feel for greater selectivity or "personalization", for various reasons.

By way of nonlimiting examples, the following applications can be cited:
a / in certain countries, such as Switzerland, a telephone banking service offers consumers who telephone the possibility of obtaining the visualization of this simulation on a teletext page, visible on their television set but also on all television sets active at this instant and equipped with a teletext decoder. This procedure obviously raises confidentiality issues. Otherwise, the message transmitted must remain sufficiently imprecise so that the identity of the requester remains "transparent". It cannot therefore be entirely personalized.

 b / the CEEFAX system, in one of its operating modes, known as "Newflash Mode", offers the possibility of forcing on the screen of televisions, equipped with a teletext decoder, the display of a banner, in overlay of the current image. As before, the banner is displayed on all TVs. For example, if the message states to call a given telephone number, there is a very real risk of saturation of the telephone network, at least the standard of the company corresponding to the telephone number displayed, since all viewers , equipped with a teletext decoder receive the same message and, what's more, at the same time. This is particularly the case when it comes to answering questions from a game show.

 c / The teletext system, according to the above-mentioned CEEFAX standard, theoretically allows the transmission of around 1000 pages. In the current state of technology, most televisions, equipped with decoders and appropriate memory circuits, can store up to 256 pages. In the near future, it will reach the theoretical limit of 1000 pages. These 1000 pages are fully renewable at each cycle. It is therefore a volume of information difficult to handle for an "average" consumer, even if it is only the 256 pages currently usable.

 In summary, in particular for the reasons indicated above (confidentiality, possible saturation of telephone networks, overabundance of information transmitted, etc.), there is a real need for selective, even personalized, transmission of information by the teletext process.

 The object of the invention is to meet this need.

The subject of the invention is therefore a method of transmitting teletext pages comprising at least one step of transmitting video signals by a television channel and their display on the screen of a plurality of televisions equipped with a reception system. teletext data, each page conveying information of a specific type that can in particular be associated with said video signals being displayed and being received by each television set of said plurality, characterized in that it comprises the following additional steps
a / on transmission, selective association of a personalized code with at least one of said teletext pages, serving as an address for the identification of at least one of said televisions, and simultaneous transmission of information from the teletext pages with said personal identification data; ;
b / upon reception, recognition, by each of said televisions, of these personal identification codes by comparison with an identification code, linked in a one-to-one manner to this television, and acceptance of the only pages intended for this television, for memorization of the information conveyed by said page and / or display.

 The invention also relates to a system for implementing such a method.

 The invention will be better understood and other characteristics and advantages will appear on reading the description which follows with reference to FIG. 1 attached, which schematically illustrates an example of architecture of an interactive teletext system according to the invention.

 The main components are as follows: a teletext decoder 1, a microprocessor 2, a memory 4 of teletext pages, an interface circuit 3 capturing the radiation emitted by the Teiec remote control, and the screen 6 of the television set. A priori, these circuits are already present on a conventional television set equipped with a teletext system.

 In particular, a microprocessor 2 is present in most televisions and used for various functions of settings outside the precise scope of the invention.

 It was assumed, to fix ideas, that the number of teletext pages was equal to 1000: referenced p0 to p999.

 The Teiec remote control includes, as has been recalled, in addition to the conventional function keys not shown, four special function keys, referenced T1 to T4. These are advantageously the colored buttons (red, green, blue and yellow) used in the context of the above-mentioned "TOP" system. These keys are used for teletext mode.

 The Teiec remote control communicates with the microprocessor 2 via the interface 3 which receives codes specific to each key and, after optoelectronic conversion, transmits, via a link 30, binary codes corresponding to the microprocessor 2.

 Instead of the Teiec remote control, it is of course possible to use the control buttons on the instrument panel (not shown), as long as the function keys, T1 to T4, are also present. .

 In itself, this architecture does not differ fundamentally from the architecture of conventional teletext circuits.

 In a conventional system, when the television receives teletext information, it is stored in the memory 4. As a function of the address data associated and decoded by the decoder 1, the information is transmitted by the link 10 to the appropriate pages, p0 to pggg.

 According to an important characteristic of the invention, during transmission, a "data or personal identification code" is associated with given page numbers or with series of page numbers.

 “Data or a personal identification code” is understood to mean, within the framework of the invention, any data associated, in a one-to-one manner, with a certain number of viewers, at least with the televisions in their possession.

 Advantageously, the above-mentioned "personal identification data or codes" consist of the serial numbers of the televisions, which are unique.

 In practice, a field describing the "target" serial numbers of this page is associated with each teletext page number transmitted.

 It is therefore necessary that the teletext page distributor is in possession of this data.

 Different procedures are conceivable. By way of nonlimiting example, the user who has just bought a television set can be asked to dial a free telephone number and to communicate the serial number to the switchboard, as well as '' other personal data concerning him: centers of interest, in particular in relation to the nature of the information usually transmitted by teletext (sport, culture, etc.). Finally, additional information, for example for later advertising purposes, may be requested: profession, family composition. Alternatively, the viewer may respond in writing by completing a questionnaire which will be attached to their purchase or transmitted later. Naturally, the user must be able to obtain guarantees as to the anonymity of the answers provided, and the procedure used must meet the legislative requirements in force in the country concerned.

 By this procedure, the broadcaster can create a file of television numbers, associated with more or less complete household descriptions depending on the applications envisaged and the responses provided by viewers. It will thus be able to transmit targeted teletext pages, by type of household.

 According to another characteristic of the invention, the microprocessor 2 receives a fixed data item, constituted by the serial number of the television set. In FIG. 1, it has been assumed that this number is stored in an autonomous circuit 5 and transmitted to the microprocessor 2 by the link 50. Naturally, any other conventional embodiment can be imagined, for example a number recorded in the fixed memory (not shown) which is usually provided with the microprocessor and which is also used for storing the microprograms necessary for the proper functioning of the system.

 When the microprocessor 2 recognizes, among the teletext data stream received, the address associated with the television, that is to say its serial number in the preferred embodiment of the invention, the page in question is stored in the memory 4 and can therefore be displayed on screen 6 of the television.

 We will now describe some examples of application of the method according to the invention, among others possible.

In a first example, it is assumed that the televisions whose serial numbers are included in a first range of numbers (to fix the ideas, the televisions whose serial numbers are included in the range
AA1235-FE4321, for example) are interested in stock market prices. We will reserve, for example page 1000 for this type of information. When the televisions concerned recognize their address, according to the procedure previously explained, the information is then displayed and / or stored in the memory 4 of these processors.

In the same way, viewers may be interested in the results of certain sports, such as football (to fix the ideas, televisions whose serial numbers are included in the BC3342-DD4444 range, for example)
For example, page 900 will be reserved for this type of information.

 There can of course be overlap, with some televisions receiving both types of information. If there is no overlap, the same page number (number 1000), for example, can transport the two pieces of information successively, which increases the possible information rate.

 For reasons of compatibility with the existing teletext system, if the teletext page carries a particular code, for example the code "ALL" instead of the identification number, this page will be accepted by all televisions equipped with a teletext system. In other words, there is no longer any personalized transmission.

 In a second example, we assume that all viewers are invited to dial a telephone number. This could be the case of a game show, for example. As indicated, the risks are then significant that there will be saturation phenomena in the telephone network.

 The method according to the invention allows the display on television screens in a staggered manner. In fact, it is possible to associate with the information transmitted by teletext, that is to say in particular the telephone number to be called, ranges of television numbers. It follows that only televisions recognizing their address will be able to display the telephone number to dial on the screen 6, for example by superimposing the current video image.

 In this way, a sequential display of the aforementioned telephone number is organized, for example in two-minute periods and on 1000 televisions at a time. This avoids traffic peaks on the telephone network. These parameters characterizing the sequential display can naturally be modulated in real time by measuring telephone traffic. You can play on one or the other parameter or both: increase or decrease the number of television sets addressed simultaneously, increase or decrease the time interval.

 In a third example, we will focus on the case of the so-called "GEMSTAR" system. This allows, at the touch of a button on the Teîec remote control (or on the TV's dashboard), to display a message related to the television program being displayed. In this context of application, advantage can be taken of the method according to the invention.

 To fix ideas, when it comes to an advertising message, with a conventional teletext system, one can only display information or a message of general significance. By implementing the method according to the invention, it is now possible to personalize this message. Indeed, as has been indicated, the teletext page broadcaster has a file comprising the serial numbers of the televisions each associated with a certain amount of information. This information was provided by the users.

 It is assumed that, among this information, appears the address of the owner of the television, at least the city or the postal code. From this information, it is then easy for the broadcaster to selectively display, on a given television set, knowing its serial number, The address of the firm closest to the televiewer's home, firm selling the products whose advertising message is being displayed.

 In a fourth example, also knowing address data, for example the postal code, it is then possible to transmit, on a particular page number, data characterizing the transmitters of the region, for example a table of the frequencies of the transmitters of a region, for one or more channels. From this data, the television can be programmed fully automatically.

 On reading the above, it is easy to see that the invention achieves the goals it has set for itself.

 It should be clear, however, that the invention is not limited only to the examples of embodiments precisely described, in particular in relation to FIG.

 In particular, although perfectly suitable, the serial number of the television is not the only personal identification data that can be used. We could just as easily enter a code in memory, using the remote control for example, code provided by the broadcaster. This code could also be entered using a magnetic card or a so-called smart card. Whether it is the serial number of the television set or a code recorded in another way, this data could also be used, not "in the clear", but in encrypted form, using an appropriate algorithm. This operation could advantageously be carried out under the control of the microprocessor, or quite the contrary, by using specialized circuits.

 It should also be clear that the method according to the invention is not fixed. It is possible, at any time, to update the information contained in the file held by the broadcaster, in particular to take into account the sale of a television set (the new owner may have interests in changes of domicile), moving the viewer to another traffic area or any other modification.

 Finally, a viewer can own two or more TVs. These televisions can perfectly be associated with specific broadcasting profiles.

In fact, in the preferred embodiment of the invention, it is the serial number of the television which characterizes its behavior with respect to information transmitted by teletext, received by all televisions but accepted selectively by virtue of the address field transmitted in simultaneity with teletext pages.

Claims (13)

 1. Method for transmitting teletext pages comprising at least one step of transmitting video signals by a television channel and their display on the screen (6) of a plurality of televisions equipped with a teletext data reception system (1, 4), each page conveying information of determined type which can in particular be associated with said video signals being displayed and being received by each television set of said plurality, characterized in that it comprises the following additional steps  a / on transmission, selective association of a personalized code with at least one of said teletext pages, serving as an address for the identification of at least one of said televisions, and simultaneous transmission of information from the teletext pages with said personal identification data;  b / upon reception, recognition, by each of said televisions, of these personal identification codes by comparison with an identification code (No), linked in a one-to-one manner to this television, and acceptance of the only pages intended for this television, for storage (4) of the information conveyed by said page and / or display (6).  2. Method according to claim 1, characterized in that said personal code identifying the television set consists of its serial number (No) and in that this serial number (No) is associated with at least one of the teletext pages transmitted .  3. Method according to claim 2, characterized in that the television's serial number (No) is transmitted by telephone to a broadcasting center for said teletext pages during an initial installation procedure for this television.  4. Method according to one of claims 2 or 3, characterized in that in addition additional data are associated with said serial number (No) and recorded in a file, so as to select said teletext pages intended selectively for said televisions according to their informational content.  5. Method according to claim 4, characterized in that said additional data translate centers of interest of the owners of said televisions so that only teletext pages containing information corresponding to these centers of interests are accepted by these televisions .  6. Method according to claim 4, characterized in that said additional data is geographic address data associated with the location of said televisions, so as to selectively transmit teletext pages associated with said personal codes (No) associated with information for televisions located in a specific geographic area.  7. Method according to claim 6, characterized in that the information conveyed by said teletext pages consists of frequency tables used by television transmitters serving a geographic area determined by said geographic address data.  8. Method according to claim 4, characterized in that said additional data is marketing data supplied by the owners of said televisions, so as to selectively transmit teletext pages, associated with said personal codes (No), only to televisions responding to said marketing data.  9. Method according to one of claims 2 or 3, characterized in that serial numbers of televisions included in a determined range are associated with at least one teletext page number during a determined time interval, so as to selectively address televisions whose serial numbers are included in this range of numbers during said time interval, and that, at the end of this time interval, another range of television numbers is selectively addressed, the process repeating until 'upon exhaustion of all or part of the television numbers that can be addressed, so as to carry out a sequential addressing of said televisions.  10. Method according to claim 9, characterized in that said video signals displayed on the screen (6) of the television set relating to a television game, The information conveyed by said teletext pages associated with said personal codes (No) is a telephone number to be dialed by the viewer, this information being displayed in superimposition of said video signals displayed on the screen (6) of said televisions.  11. Method according to any one of the preceding claims, characterized in that a particular code is associated with at least one of said teletext pages in place of said personal identification codes, so that each of these pages is received and accepted by all said televisions, for memorization (4) of the information conveyed by said page and / or display (6).  12. System for implementing the method according to any one of the preceding claims, characterized in that it comprises at least one teletext decoder (1), a teletext page memory (4), a signal processing device (2) comprising calculation circuits, and a control device of the key keyboard type (Telec), characterized in that it further comprises means for comparing (2, 5) said personal identification code associated with the number teletext pages received with a personal identification code (No), associated in a one-to-one manner, with said television, so as to select and accept only the teletext pages for which said comparison is positive.  13. System according to claim 12, characterized in that said signal processing member is a microprocessor (2) and in that, said personal identification code consisting of the serial number (No) of the television, this microprocessor (2) performs said comparison between this serial number (No) and the personalized identification codes associated with the numbers of said teletext pages, received via said decoder (1) and authorizes, when the comparison is positive, the storage of these pages teletext in said page memory (4) and / or their display.