FI87293B - FOERFARANDE FOER MOTTAGNING AV PERIODISKT UPPTRAEDANDE TELETEXTDATA. - Google Patents

Abstract

In a teletext system, in order to be able to "thumb through" the programme summaries of several days of transmission without making considerable investments in the teletext decoders on the recipient side, it is proposed to submit in the form of a tabulation on one separate page of teletext the page numbers of the total quantity of teletext pages in a repetition cycle or in a part of the latter, and to insert them in an intermediate memory on the recipient side. If the user has selected a precise teletext page, a check is made by comparing, with the page numbers inserted in the intermediate memory, whether the desired number of the teletext page figures in the cycle or in a part of the latter, after which said page is looked for if necessary. Furthermore, the decoder automatically checks on the basis of the number of the desired teletext page, and comparing again with the page numbers in the intermediate memory, whether the numbers of the following teletext pages figure in the cycle or in a part of the latter, after which a search is made for the following pages identified as figuring in said cycle, which are inserted in the intermediate memory and reproduced upon a special instruction from the user.

Description

87293

The invention relates to a method according to the preamble of claim 1. Such a method is known from the journal "Funkschau", volume 6, 1985, pp. 53-56.

It is known from this publication to separate teletext data transmitted periodically in a television signal 10 and to cache them teletext pages compiled into a page cache. Because the page cache has only a small capacity of two or four pages, only certain teletext pages whose numbers have been pre-stored by the user in the page number-15 scrap are cached. If these stored page numbers do not exist in the playback section or in a certain part of the section, the teletext page in question will not be found, and the search operation will continue without interruption. In such a case, the user does not know whether the waiting time was too short or whether the desired teletext-20 vu playback period is missing. In addition, the area cached for this purpose remains unused. The same inconvenience occurs when the user presses the "next page" key to display the next page from the pre-programmed page order.

The object of the invention is to improve a method such as that mentioned at the beginning, so as to avoid unnecessary waiting times in the selection of the desired or "next" teletext page and in which all the memory locations of the page cache are optimally utilized.

According to the invention, this object is solved according to the features of claim 1, which substantially shorten the prior art search procedures and further ensure the permanent use of each memory location of the side cache.

35

Preferred variations of the method according to the invention appear from the dependent claims.

2 87293

In the following, the invention will be explained in more detail with the aid of the drawings. The drawings show:

Figure 1: Contents of a special teletext page showing all teletext pages in a section or part of a section, with separate pages being provided with special symbols;

Figure 2: A series of page numbers that can be selected from the currently selected page by pressing a special selection key;

Figure 3: Block diagram of a device operating according to the method of the invention; 15

Figure 4: A block diagram of the extension of the embodiment of Figure 1 with a plurality of specific teletext pages separately for page numbers, subpages, (multiple) page numbers, and page titles; and 20

Fig. 5: A schematic representation of a TV receiver showing a user guide title obtained by the embodiment of Fig. 4.

Figure 1 illustrates the content of a particular teletext page that is transmitted randomly during a period and which is automatically selected and interpreted by a teletext decoder on the receiver. As can be seen in Figure 1, the numbers of pages (which may also include multi-page pages) appearing in one teletext section or part of a section are read sequentially in a table of 40 columns and 20 rows. In this case, page numbers # 410, # 430, # 440, # 500 are marked with the jump symbol "/", whereby these marked pages are the first pages in a group of pages with a content content of 35, e.g. program lists for a given date. Because page # 440 is a multi-page page comprising pages # 440/1 and # 440/2, unlike the other pages in the example cases considered, it is marked with the jump code 3 8 7 29 3 and not with the jump code. In the example of Figure 1, the following group-specific order applies: # 410, # 411, # 412 Program list pages for the date of transmission of the ARD programs 5 on January 1, 1987, with individual pages # 411, # 412 and # 413 being marked with a "+".

# 430, # 431, # 432 Program list pages for the 10 broadcast dates of the ARD programs on January 2, 1987.

# 440/1, # 440/2, # 441, Program List Pages ARD- # 442 for the broadcast date # 443/1, # 443/2, # 443/3, January 3, 1987, when 15 # 443/4 multipart page # 443 is marked with the symbol "d".

# 500 ZSF Program List Page for January 1, 1987.

20

In connection with the transmission of a special teletext page according to Fig. 1, only those lines out of 20 lines with entries are transmitted, i.e. in the example case of Fig. 1 only lines no. 8, no. 9 and no. 11. Due to the matrix-like structure of the table-25 machine according to Figure 1, a page number is obtained on the basis of the associated column number and the transmitted line number. The symbols "+", "/", "B" and "d" are moved in plain language.

30 Due to the group-specific arrangement, it is possible, as shown in Fig. 2, to "scroll forward" in the group of program list pages by pressing the "next page" key or to select the first page of the next group directly by pressing the "jump" key.

35

Figure 3 shows a block diagram of a teletext receiver operating according to the method of the invention. The teletext information is separated from the video signal in the separation block 10 and compressed into 87293 4 individual pages. Each page is routed on the output line 11 to the gate circuit 30, which feeds the incoming page via the read line 31 to the cache 40 if the control circuit 50, described in more detail below, provides an operation signal to the gate circuit on the output line 51. In addition, the control circuit 50 via the second output line 52 provides for the assignment of a side cache 40 for the read operation. The side cache 40 is also read under the control of the control circuit 50 via the third output line 53.

10

The page numbers of the teletext pages appearing on the line 21 from the page number release circuit 20 are fed to the control circuit 50. To this end, the release circuit 20 detects the meru of each video text page nu-15 fed from the line 11 by the branch line 12. In addition, the control circuit 50 is associated with a user-controlled input circuit 70 having a keyboard 71 for entering a desired page number, and a key 72 labeled "next page" and a key 74 labeled "jump". The desired page number is input to the control device by line 711, while the command "next page" or "jump" is input to control circuit 50 on line 721. When a special page with page number information in a section or section is present, it is automatically entered in page cache 40. . . 25 on the read line 54 to the control 50, where the page numbers are detected and stored in the page number memory 60, which in turn is connected via a bidirectional bus 61 to the control circuit 50.

Assume, for example, by pressing the keypad 71, the user has selected page number 100. After pressing the "next page" key, the control circuit 50 - starting from the currently selected page number - issues the next page number in the page number memory 60, namely page 35 410 (see also Figures 1 and 2). As soon as this page appears in the section where the control circuit 50 receives an indication of the release circuit, an operation signal I, 87293 5 appears on the output line 51 to the gate circuit 30, after which the page 410 is placed via the line 31 in the memory 1 of the side cache 40. said, under the control of the control circuit 50 on the output line 52. The count-5 then generates a read command 53 on the output line 53 to the memory location number 1, after which the page numbered 410 is read on the bus 41 from the page cache 40 to the processor 73. components R, G, B and S, for example 10 on the TV screen.

In addition, when the user's request for page number 410 is fulfilled, the control circuit 50 automatically places the pages following number page memory number 2, number 3 and number 15 following the page cache 40, respectively, corresponding to the page number memory.

As the next page number, the page number 411 is found in the page number memory 60, and thus, as already described in the section, it is cached in the memory location number 2. Correspondingly, the following pages are followed.

20

Each time the user "scrolls" through the pages 72, the control circuit 50 reads the next memory location in which the "next" 25 pages are stored in terms of content as a result of the read-in operation described above.

This ensures that the user can also "browse" the pages quickly. In the event that the user "scrolls" so fast that the next page 30 in the period has not yet appeared in the period and is not yet stored in the page cache 40, the control circuit 50 may provide an indication 73 on the display 70 on the display 70 requiring the user to wait.

35 Pressing the "Next Page" key 72 frees up the memory space of the already read page, which in this case is again reserved for the next page in the section that has not yet been cached.

»6 87293

With the method according to the invention, multi-part pages can be cached and read more easily. In addition, the control circuit 50 uses the page number memory 60 to know if there are any, and if so, how many multi-5 pages there are in the period, in which case it can influence the paging and storage events of the page cache 40 so that gradually all multi-page pages are cached. a.

10 Pressing the "jump" key 74 performs a step similar to pressing the "next page" key.

After pressing the "Jump" key, the control circuit 50 transmits - starting from the currently selected page - the next page number in the page number memory, which is provided with a jump ID. If that page is not yet in the page cache 40, reading that page into the page cache 40 will follow as soon as it appears in the episode. After counting, the page is displayed on the screen.

20

Based on the page number belonging to the jumped page, the allocation of other memory slots of the page cache 40 for subsequent pages follows, according to the page number memory 60.

.25 It may be appropriate to keep a specified portion of the page spacing memory 40 reserved only for pages which, from the page number just selected, can be selected directly by pressing the "jump" key. In this variation, 30 pages are automatically stored in these special areas, which - starting from the currently selected page - are provided with a jump ID. Pressing the "Jump" key reads the current next memory location in this special memory area and displays it on the screen.

From the above connection, it is clear that the method according to the invention uses the capacity of the page cache 40, e.g. 4 or eight pages, in an optimal way, allowing the user to "scroll forward" the pages of a teletext episode or part of a episode with the minimum waiting time, similar to a magazine. With the press of a "jump" key, the respective first page in a group of substantially related pages can be selected directly in succession. By pressing the "next page" key, the pages of the group can be selected in sequence.

Figure 4 illustrates an extension of the embodiment of Figure 1.

10

A special teletext page is used to identify all pages in a teletext section or part of a section. In addition to the hop ID of the group of content-related pages (Figure 1), a second hop-15 ID is used for a subject area with multiple content-related groups. Other symbols have been arranged for the subheading and program lists.

The second teletext page contains identifiers for each of the 20 multipart pages transmitted, which have special identifiers for the number of subpages.

A teletext page is used for additional information, e.g. for a title or special codes to answer-. .25 pages can be selected directly without knowing the page number.

Figure 5 shows by way of example how a decoder can display headings from a supplementary information table on a screen to guide a user. The information bar shows the left-30 racket area "ARD" associated with the newly selected page "ARD Programs Today". Next to it is the next group of "programs for tomorrow" that can be brought up with a jump p key. Just to the right of the decoder's information line is the next area "Preliminary program information -35 ZDF", which can be immediately displayed by pressing the corresponding "area key".

Claims (5)

8 87293 A method for receiving repetitive teletext information in a section or part of a section included in a television signal, wherein the teletext information is separated from the television signal, the information on each teletext page is collected and the teletext pages thus assembled are stored, the page numbers of the teletext pages are stored stored page numbers, and if the comparison result is positive, the desired teletext page is searched for in the playback period or part of the period, and if found, stored in the page cache, and the next page location is further selected by pressing the "next page" key and the memory contents are displayed. "next teletext page", characterized by the following method steps: (a) the page number memory stores the numbers of all teletext pages actually in the replay period or part of a section, if these page numbers are taken from a table which is sent and received as a separate teletext page; b) based on the specified teletext page selected by the user, determining by comparing with the page numbers stored in method step a) whether the desired teletext page number is in the replay period or part of a section, and only after the desired teletext page number is detected; further to the page numbers stored in the page number memory, if the next page number exists in the playback sequence or section 30 in numerical order, and only after the existence of that page number is detected, the search operation is started and the found teletext page is stored in the next cache memory location. 35 A method according to claim 1, characterized in that when the multi-part pages occur in a repetition section or part of a section, their subpage numbers are transmitted as a table within the framework of another separate teletext page. A method according to claim 1 or 2, characterized by the following additional steps: d) receiving and caching in the table jump identifiers denoting the first page of the group of related teletext pages, and e) searching for the user by selecting a specific teletext page with the "next jump" command, the page number of the playback period and the corresponding teletext page is displayed after recording. A method according to claim 3, characterized by the following additional step: f) based on the page number of the desired teletext page, automatically searching for the next page numbers specially marked as a jump ID in the replay period or part of the episode, caching them in free memory locations and displaying them with a user jump command. Method according to one of Claims 1 to 4, characterized in that plain-language headers for at least some of the page numbers transmitted in the first table are transmitted within the third special teletext page, which headers are displayed when the page number is selected. 87293 ίο