JP3473151B2 - Broadcast receiving apparatus and method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention not only watches the program data being received but also efficiently stores the program data when watching a data broadcasting program such as a character broadcast. The present invention relates to a teletext receiver and a method thereof that can be freely selected and viewed.

[0002]

2. Description of the Related Art In recent years, a coded transmission system capable of displaying news, weather forecasts, stock market, and other text and graphic information consisting of text and graphics on the screen of a home television receiver by using broadcast radio waves. Has been put into practical use, and a television receiver with a built-in receiving device for receiving the character broadcast of this coded transmission system has also been developed.

Below, regarding the conventional teletext receiver,
A description will be given with reference to the drawings. FIG. 14 shows the configuration of a conventional teletext receiver. 141 in FIG.
Is a CPU that controls the entire system, and 142 is a storage unit that holds an operation program. a is a video signal of the television, 143 is a character signal extracting unit for extracting the character broadcast data superimposed on the vertical blanking interval from the video signal a, and 144 is decoding of the character broadcast data extracted by the character signal extracting unit 143. Is a decoding unit that performs the above process and develops into display data of a character graphic for display. 145
Is a data storage unit for storing only the teletext data extracted by the text signal extraction unit 143, 146 is a memory management unit for managing the teletext data according to the control code of the teletext data of the data storage unit 145, and 147 is A display memory for holding display data expanded into a character graphic by the decoding unit 144, a display control unit 148 for performing memory address control for taking out display data from the display memory 147, and a display controller 149 for reading character broadcast data from the display memory 147. It is a TV monitor for actual display.

The operation of the teletext receiving apparatus configured as described above will be described below. The teletext signal extracting unit 143 extracts vertical blanking intervals 14H (277H) and 15H (278) from the input video signal a.
H), 16H (279H), and 21H (284H), the character signals superimposed on the four transmission lines are extracted.

Twenty-two bytes of the teletext data are superimposed on the transmission lines of the four vertical blanking intervals (22-byte data is one packet).

Details of the standard relating to teletext are described in "Teletext Broadcasting Handbook, Broadcasting Technology Development and Development Council, Kenrokugen Publishing". The definitions of "program" and "page" described in the specification follow this teletext technical handbook.

The CPU 141 stores the extracted teletext data in the data storage unit 145 via the memory management unit 146. In addition, the CPU 141 uses the data storage unit 145.
To read the teletext data from the memory management unit 146. Then, the decoding unit 144 converts the data into character / graphic data (display data) for displaying characters and graphics on the television monitor, and writes the character / graphic data in the display memory 147. The display control unit 148 reads the character graphic data from the display memory 147 and displays it on the television monitor 149.

The CPU 141 has a function of preferentially accumulating reserved teletext programs in the data storage unit 145. Further, the teletext data that is sequentially received is stored according to the remaining memory capacity of the data storage unit 145.

A method of controlling the data storage unit 145 by the memory management unit 146 will be described below with reference to FIGS. 15, 16 and 17. Figure 15 shows
The internal configuration of the data storage unit 145 and the memory management unit 146 includes N memory blocks for storing sequentially received teletext data for each packet and a position table for managing the memory blocks. The position table is
There is a one-to-one correspondence with the memory block, and a ring memory is formed for the memory block.

That is, the position table 1 indicates the position table 2, the position table 2 indicates the position table 3, and the position table N indicates the position table 1. The teletext data sequentially received is written in the ring memory. In the ring memory, the received teletext data is stored in the data storage unit 1
When the memory capacity of 45 is exceeded, new data is sequentially updated from the memory block in which old teletext data is stored.

FIG. 16a shows a packet format for actually storing sequentially received packet data in a memory block, which consists of programs, page information and packet data.
As described above, the packet data is stored from the one received sequentially. At this time, in the packet data, since the content of the teletext program is not continuous, the packet format requires the program and page information.

FIG. 16b is an internal view of the memory when the packets are sequentially stored in the memory block. When the second page of the program 5 is displayed on the television monitor, the second page of the program 5 is searched from the program and page information in the memory block, the packet data is expanded by the decoding unit 144 into a character graphic, and the display memory 147 is displayed. Transfer to.

At this time, if the second page of the program 5 does not exist in the data storage section 145, it waits until the data is sent.

Next, the case of reservation will be described with reference to FIG. FIG. 17 shows the data storage unit 1 when reservation is used.
In the internal configurations of the memory management unit 45 and the memory management unit 146, a reservation table is added to the content shown in FIG. When a user reserves a teletext program, the program is prioritized and stored in the memory. The reservation table is composed of reserved programs and the numbers of memory blocks that are prioritized. FIG. 17 shows that when the program number 100 is reserved, the memory blocks 1 and 2 are secured, and the memory blocks 1 and 2 and the remaining memory blocks 3 to N respectively form separate ring memories. There is.

When a reserved teletext program is displayed on the television monitor, a page is retrieved from the memory reserved for reservation, and the decoding unit 144 develops it into a character graphic and transfers it to the display memory 147.

As described above, the conventional teletext receiver stores and displays teletext programs.

[0017]

However, the conventional device has two problems. One is that the memory management of teletext programs is not sufficient. This is to manage the data storage unit in a ring memory format and to manage the teletext program as a file in order to improve the memory usage efficiency. I was in control. Therefore, when accessing a page of an arbitrary teletext program, packets of the page data are collected and displayed. Further, in the ring memory, when the memory is full, old data is erased in order, so that it is impossible to manage the presence or absence of page data.

Another problem is the cost of memory capacity. For example, if all NHK teletext programs are stored in the memory, at least about 1 MB is required. In the conventional device, only a memory of about 200 Kbytes is installed to store teletext programs, and it is costly to install a memory of 1 Mbyte.

The present invention has been made to solve the above-mentioned conventional problems. In order to solve the memory management problem and the memory capacity problem of a teletext program, a plurality of pages of the teletext program are treated as one file. Manage files. Then, by compressing and storing, the apparent memory capacity was increased. Also, when managing files, the memory usage efficiency is set to the same level as the ring memory format.
An object is to provide a teletext receiver and a method thereof.

[0020]

In order to achieve this object, a teletext receiving apparatus of the present invention includes a signal extraction means for receiving teletext and extracting teletext data, and a means for extracting the teletext data extracted. Among them, a teletext program selection means for selecting teletext data of at least one teletext program, a data storage means for storing the selected teletext data, and the inside of the data storage means are divided into small blocks. A function, a function of acquiring a block from an unused block according to the data size of each of the selected teletext data to form a data storage area, and releasing an unused block when an unnecessary block occurs Memory management means having a function to perform, a file management means for managing the "page" of the teletext data as one file, and the sentence And it has a configuration in which a data compression means for compressing the file management means and the file data for managing the "page" of the broadcast data as one file, and data expanding means for expanding the compressed data.

[0021]

With this configuration, in the file management means, with respect to the teletext data extracted by the signal extraction means,
The teletext program selected by the teletext program selection means is stored in the data storage means with the "page" unit of the text broadcast program as the minimum file unit. The memory management unit divides the data storage unit into small blocks, and when writing to the blocks by the file management unit, allocates blocks according to the data size for each file and manages the usage status and link information of the blocks.

Blocks are also released when files are deleted. The file can be arbitrarily compressed by the data compression means and expanded by the data expansion means.

According to the present invention having such characteristics,
It is possible to maximize the memory usage efficiency of the teletext receiver. Further, by using file management, it is possible to flexibly manage teletext programs.

[0024]

【Example】

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. In FIG. 1, 1 is a CPU that controls the entire system, and 2 is a storage unit that holds an operation program. Reference numeral 3 is a character signal extracting unit for extracting the character broadcasting data superimposed on the vertical blanking section from the video signal a, and 4 is for selecting necessary data from the character broadcasting data extracted by the character signal extracting unit 3. The teletext program selection unit 5 is a decoding unit that decodes the teletext data selected by the teletext program selection unit 4 and develops the data into display data of a character graphic to be displayed. 6 is a data storage unit for storing the teletext data selected by the teletext program selection unit 4, and 7 is a unit for dividing the data storage unit 6 into small blocks and managing the usage status and link information of the blocks. A memory management unit, 8 is a file management unit that manages the creation and deletion of files with the "page" unit of the teletext program as the minimum file unit, and 9 is a display for storing the display data expanded into character graphics by the decoding unit 5. A memory 10 is a display control unit for controlling a memory address for fetching display data from the display memory 7, and a reference numeral 11 is a television monitor for reading from the display memory 9 for actual display.

The operation of the teletext receiving apparatus configured as described above will be described below with reference to FIGS. 2 and 3. The teletext signal extracting unit 3 extracts vertical blanking intervals 14H, 15H, 16H from the input video signal a.
The character signals superimposed on the four transmission lines of 21H are extracted. The teletext data is superposed by 22 bytes on each of the transmission lines of the four vertical blanking intervals (22-byte data is one packet).

From the extracted teletext data, the teletext program selection unit 4 selects only predesignated teletext programs (for example, programs reserved by the user). The selected program creates a file for each page of the program, and the file management unit 8 manages the page by page.

When the file management unit 8 creates a file, the memory management unit 7 secures one memory block in the data storage unit 6. After that, the file management unit 8 writes teletext data (packet data), and when the capacity of the memory block becomes full, the memory management unit 7 secures a new memory block.

FIG. 2 is an explanatory diagram in the case of actually writing teletext data (packet data) in the memory block. Since writing to the memory block is performed in packet data units, the size of the memory block is a multiple of the packet data.

In this embodiment, one memory block is 1
Two pieces of packet data can be stored, and this figure shows a state in which data for three pages is stored in the data storage unit 6.
The first page data consists of 10 packets, the second page contains 6 packets, and the third page contains 15 packets. The memory management unit 7 acquires one block for each of the data of pages 1 and 2 and two blocks for each of the data of page 3.

FIG. 3 is an explanatory diagram of a case where a new file is created and data is written to the selected teletext data. In FIG. 3, the file management unit 8
The file table 7 includes a file name created by the file management unit 8 and a memory block number (memory management table number) indicating the first memory block of the data storage unit 6 that stores the file. The memory management table of the memory management unit 7 has a one-to-one correspondence with the memory blocks of the data storage unit 6, and stores the usage status of the memory blocks and the link information between the blocks. If the memory block is not used, "0" is stored. If the block is in use, the next linked block number,
Alternatively, if it is the final block, "-1" is stored.

In the case of FIG. 3A, the file management unit 8 creates a page file "name1" and stores it from the memory block 1 of the data storage unit 6. Figure 3
In (b), since the memory capacity of the memory block 1 is full, a new unused memory block 2 is acquired. Then, as the link information of the memory block, "2" indicating the next block is stored in the memory management table 1 in the memory management table, and "-1" indicating the last block of the file is stored in the memory management table 2. The same applies to the other page files “name2” and “name3”.

As described above, since all teletext program data can be managed in file units, when expanding an arbitrary file in the display memory 9, access to predetermined program data can be made more easily than in the conventional ring memory format. And get faster.

Further, since the teletext data is managed in file units, even if the capacity of the data storage unit 6 becomes full, the teletext data is forcibly ordered from the oldest as in the ring memory format shown in the conventional example. Will never be deleted. That is, the CPU 1 can store / manage teletext data using the file management unit 8. As a method of deleting the file, a method of deleting from the teletext program file that the user is not currently viewing is conceivable.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to FIGS. 4, 5 and 6. FIG. 4 is an overall system configuration diagram in the second embodiment, and 1 to 7 and 9 to 11 are similar to the configuration of FIG. The difference from the configuration of FIG. 1 is that the file management unit 8 has a page search function 8a
Is the point added. FIG. 5 is a memory internal configuration diagram of the data storage unit 6 in the second embodiment. The operation will be described below.

In this embodiment, a case where a file unit is a "program" of teletext will be described with reference to FIG.
When the teletext program is composed of three pages as in FIG. 3, the memory management unit 7 acquires one memory block when writing the first page. Then, the file management unit 8 actually writes in the memory. When writing the second page, the memory block can still write two packets, so the first two packets of the second page are written. After that, a new memory block is acquired and the remaining 4 packets are written. The same applies to the third page. By using multiple pages as one file, the unused memory in the memory block can be reduced. (If the memory block is around 1 Kbyte, the page file management has a memory usage rate of about 70%. Then about 95
%).

FIG. 6 shows the internal structure of the program file shown in FIG. The first page of the program file comprises a program data header indicating that the next data is program management data, and program management data such as the total number of pages of the program, the program data length, and the program form. The second page consists of a page data header indicating that the next data is the first page of the teletext program and the program data of the first page. On the third page, the next data is 2 of the teletext program. It is composed of a page data header indicating the page and program data of the second page.

Since the data of the first page of this program file is the program management information of teletext, it is not necessary to manage it as page data (the same applies to the "page" file in other embodiments).

The page search function 8a shown in FIG. 4 can detect a predetermined page by searching the program data header and page data header in the program file from the top of the page.

As described above, file management is performed for a plurality of "pages" (in this case, in units of teletext programs), so that memory usage efficiency can be improved. When accessing a predetermined page, the page search function 8a
Can be used.

(Third Embodiment) The third embodiment of the present invention will be described below with reference to FIG. FIG. 7 is a block diagram for explaining file management in the present embodiment in which the file unit managed by the file management unit 8 of FIG. 1 is a "broadcast" program of teletext and a file / page conversion table is provided. . Except for the file management unit 8, the system configuration of the first embodiment is the same as that of FIG. The operation will be described below.

The file table of the file management unit 8 of FIG. 7 is similar to the file table of FIG. 3, and the file managed by the file management unit 8 and the number of the first memory block of the data storage unit 6 that stores the file. (Memory management table number) and a conversion table address indicating an address of the file / page conversion table as an additional function.

When a program file is created, a file / page conversion table for the file is created at the same time, and the start address of the file / page conversion table is stored in the conversion table address of the file table. Then, when the file management unit 8 writes the teletext data of the program file in the memory block, the page number and the page size are recorded in the file / page conversion table.

When the predetermined page is searched after writing the teletext program data in the memory block, the start address of the predetermined page can be obtained from the file / page conversion table without searching from the top of the page. Therefore, high-speed file access becomes possible.

For example, when retrieving page number 3, the start address of the page data of page number 3 can be obtained by adding the page sizes of page number 1 and page number 2.

As described above, the file management unit 8 manages files for each program of teletext and has the file / page conversion table, so that high-speed access to predetermined page data becomes possible.

The page size in the file / page conversion table may be calculated by storing the top address of each page in advance and storing it, or omitting the page number and starting from the first page. Only the page size or the start address may be stored.

(Fourth Embodiment) The fourth embodiment of the present invention will be described below with reference to FIG. FIG. 8 is a configuration diagram when the file / page conversion table included in the file management unit 8 of the third embodiment is incorporated into a program file. Except for the file management unit 8, the system configuration of the first embodiment is the same as 1 to 7 and 9 to 11 in FIG. The operation will be described below.

The area for the file / page conversion table in the memory block of the data storage unit 6 of FIG. 8 is checked beforehand by checking the page number of the program file with the program page header when the program file is created. The memory size used in the conversion table is secured from the beginning of the file in the memory block.

When the file management unit 8 writes the packet data of the program file in the memory block,
The page data header is detected and the page number and page size are recorded in the file / page conversion table.

When this method is used, it is not necessary for the file management unit 8 to provide a conversion table address for holding the file / page conversion table in the file table. Further, it is not necessary to hold the file for the file / page conversion table.

(Fifth Embodiment) A fifth embodiment of the present invention will be described below with reference to FIG. FIG. 9 is an overall system configuration diagram in the fifth embodiment, and 1 to 11 are the same as the configuration in FIG. The difference from the configuration of FIG. 1 is that a data compression unit 12 that compresses a program file managed by the file management unit 8 and a data decompression unit 13 that decompresses the compressed program file are added. Further, the file management unit 8 may have any of the functions of the first to fourth embodiments, but in this embodiment, the file management unit 8 having the functions of the fourth embodiment will be described. The operation will be described below.

When the program file is displayed on the TV monitor, the decoding unit 5 develops it into display data of character and graphics, and transfers it to the display memory 9 to display it on the TV monitor 11. Same as 1.

However, the program file of the file management unit 8 is not used except when it is displayed on the television monitor and when the program is updated. Therefore, the program file can be compressed and stored in the data storage unit 6 after the creation of the program file is completed, thereby improving the efficiency of use of the memory. When a program update occurs, a program file is created again and compressed.

Received program file (non-compressed file)
When the storage of the program is completed, the data compression unit 12 compresses the program file, stores it as a compressed file, and deletes the uncompressed file.

When referring to a program file that is a compressed file, the data decompression unit 13 decompresses the compressed data, and then the decoding unit 5 expands the data into display data of a character graphic for display. And is displayed on the TV monitor 11.

As described above, when the teletext data is stored by compressing and storing the program file using the compression algorithm and expanding only the required file, the memory usage efficiency can be increased by about 40%. it can.

Huffman coding and "Lempel-Ziv (LZ) coding" are examples of compression methods for character data. The data compression method is described in "Data compression technology has become established in personal computers and large machines (Nikkei Electronics / 1993.5.10)". In this embodiment, LZ encoding is used as the compression method.
Recently, LZ encoding is often used as a compression method with a high compression rate. As an algorithm, compression is realized by registering a past character string as a dictionary, comparing the character string in this dictionary with the current character string, and finding a matching character string. This method requires a dictionary size of at least about 1 Kbyte.

Since each "page" of the teletext program has an average length of about 1 Kbyte, the compression rate is not good even if compressed in "page" units. In the case of a program unit, the compression rate is improved because the average is about 10 Kbytes.

(Sixth Embodiment) A sixth embodiment of the present invention will be described below with reference to FIGS. FIG. 10 is an overall system configuration diagram in the sixth embodiment, and 1 to 13 are similar to the configuration in FIG. 9 is different from FIG. 9 in that a file archive unit 14 that collects files managed by the file management unit 8 is added. The operation will be described below.

FIG. 11 is a diagram for explaining an operation of collectively compressing a plurality of files into an archive compressed file and decompressing a predetermined file from the archive compressed file in this embodiment.

When the storage of the predetermined page files of the received teletext data is completed, the file archive section 14 puts the page files together.

The archiving method at this time is summarized when five files are arranged in order from the page file having the smallest page number. The number of files to be collected is 5 files in consideration of the average number of pages of teletext programs (about 10 pages), the processing time at the time of compression, and the like. The number of files may be set for each teletext program.

For example, when the teletext program consists of 8 pages, the file archive section 14 has 1 to 5 pages and 6 pages.
~ 8 pages are combined into one file.

The case of compressing an archive file will be described with reference to FIGS. 11 (a) and 11 (b).

In FIG. 11A, when the teletext program is composed of 3 pages, the file archive section 14 collects 1 to 3 pages. At this time, the file archive unit 14
The total number of files and file names (for example, the page number name is the page file name) and the size of each expanded file are written in the compressed file / file conversion table 14a. And the archive file is
It is stored as an archive compression file by the data compression unit 12.

FIG. 11B shows a case where each file has a compressed file / file conversion table 14a in the archive compressed file. In this case, the data compression unit 12 writes the compressed file / file conversion table 14b into the archive compressed file when the compression of the archive file is started.

The compression of files collectively is due to the nature of the LZ compression algorithm, as described in the fifth embodiment. That is, since the average length of each "page" of the teletext program is about 1 Kbyte, if the file unit is "page", the compression rate is not good even if only one file is compressed. By compressing collectively, the compression rate in the LZ method is improved as compared with the case of "page" unit.

Next, the case of decompressing a predetermined file from the archive compressed file will be described with reference to FIG. FIG. 11C is a diagram when only the third page file is decompressed from the archive compressed file described in FIG. 11B.

Compressed file / file conversion table 14
b is used to decompress only a specific compressed file in the archive compressed file. The data decompression unit 13
Due to the nature of the LZ compression algorithm, decompression can be performed only from the beginning of the file.

Therefore, when decompressing a specific file, decompression is performed while comparing the data size of the decompressed file / file conversion table 14b with the sequentially decompressed data size, and the decompressed data of only the specific file is retained. The decompressed data other than is discarded.

When only a certain specific file being compiled is needed, it is not necessary to decompress other files on the memory.

As described above, the compression rate is increased by collectively compressing / expanding the files in "page" units. Further, it becomes easier to change the page data for each "page" in accordance with the update of the teletext as compared with the file for each program.

By devising the compressed file name, the file name in the archive compressed file need not be stored in the compressed file / file conversion table.

For example, when the teletext programs are grouped in order from the file with the smallest page number, the files archive-compressed from pages 1 to 5 as shown in FIG. 11 (d) are "05.Z" and pages 6-8. The file that is archive compressed is "08.Z". At this time, the maximum number of files to be collected is 5. A compressed file / file conversion table 14c in each archive compressed file,
By storing the number of files initially collected and the file size from a small page, it is possible to know which page has the file size without storing the file name. In the case of "08.Z", it can be understood from the file name that pages 6 to 8 are stored in this summary. And like "05.Z", you can see the size of the page file corresponding to the page.

(Seventh Embodiment) A seventh embodiment of the present invention will be described below with reference to FIGS. 12 and 13. In the present embodiment, file management when the file management unit 8 of the first to sixth embodiments has a directory structure will be described. In this case, the file unit is "page" of the teletext program.

FIG. 12B is an explanatory diagram when the file management unit has a directory structure. A channel directory layer is provided in the root directory. When the number of channels is 6, there are 6 channel directories. A program directory layer is provided in each channel directory. When the number of programs is 50, there are 50 program directories. Further, a page file is created in each program directory.

Also, in the program directory, an archive compression file in which page files are collected by the file archive section 14 of FIG. 10 and compressed by the data compression section 12 is also placed.

FIG. 12A shows file management when the directory structure is not included. If you do not have a directory structure, all files will exist in the root directory. For example, the number of teletext channels is 6, each channel has 50 programs,
If each program consists of 10 pages,
There are 6 × 50 × 10 = 3000 files. Searching for a single file from these files takes a considerable amount of time, and file management becomes complicated.

As described above, each page file has a three-layer directory structure including a root directory, a channel directory, and a program directory, so that the page file search, that is, the search for designating the channel, program number, and page number, can be speeded up. This makes it easier to manage files.

Further, by having a directory structure, when deleting files managed by the file management unit 8 when the memory is full, etc., one or more files in each program directory are left, You can easily delete other files.

In the case of FIG. 12B, channel [1]
Delete from program [1] page [2], channel [n] program [4] page [5].

As a result, there is a high possibility that each program directory will have one or more page files, and the program desired by the user can be searched and displayed for at least one page without waiting time.

(Embodiment 8) Hereinafter, Embodiment 8 of the present invention will be described with reference to FIGS. In the present embodiment, file access in the file management unit 8 and the archive file management unit 14 when reading and writing a file on the multitask OS in the system of FIG. 10 will be described.

In FIG. 13, reference numeral 131 denotes a storage task for storing the teletext data obtained through the teletext program selection unit 4 into a page file by the file management unit 8 to store the data and update the data. Reference numeral 132 denotes a compression task that archives the file in the file archive unit 14 and then compresses the file to create an archive compression file. 133 is a decompression task that decompresses one or more files from the archive compression file. Reference numeral 134 is a file management unit 8. This is a retrieval task for retrieving a predetermined file from the stored files and expanding it in the display memory 9 via the decoding unit 5.

Similar to the data compressing unit 12 of the sixth embodiment, the storage task requests the compression task 132 to collectively compress the page files 1 to 5 when the storage of the page files 1 to 5 is completed.

Compression task 1 requested by the storage task 131
32 collectively compresses the page files 1 to 5 to create an archive compression file. At this time, either the accumulation task or the compression task may be put together using the file archive unit 14. The compression task deletes the page files 1 to 5 upon completion of the compression. The time required for compression is about 0.5 seconds (measured with a 4MIPS CPU).

In the teletext, page data of the same program is transmitted page by page in about 20 seconds.

Due to this property, the storing task does not need to write the page file while the compressing task reads the page file and creates the compressed file, and the file control becomes easy.

When displaying a teletext on a television monitor,
The search task 134 file searches the decompressed file managed by the management unit 8. If the decompressed file does not exist, the archive compressed file is searched. If it exists as an archive compressed file, the file is decompressed by the decompression task 133 and read as a page file. Then, the data is written in the display memory via the decoding unit 5.

Next, when a page update occurs, first,
The storage task retrieves the decompressed page file. If the file does not exist, a new page file is created and page data is stored. At this time, a new page file is created even if the archive compressed file exists. If the decompressed page file exists, overwrite it.

When displaying a teletext on a television monitor,
As mentioned above, the search task requests the decompression task to decompress data and decompresses the page file from the archive compression file, but I will explain the case where the same page file is updated while decompressing the page file. .

In this case, the accumulation task forcibly deletes the page file whose data is being expanded and newly creates an updated page file. Since the decompression task cannot write data to the file, it notifies the requesting search task of the decompression error. When the search task is notified of the error by the decompression task, it waits for the completion of the accumulation of the update data file and then extracts the data from the file.

As described above, by using the above-mentioned file access control, the processing in the case where simultaneous writing from a plurality of tasks to a single file or writing to a file being read occurs on the multitasking OS Can be done.

As a result, since it is not necessary to create a temporary file for file editing for file access control, the memory capacity for accumulating teletext data is not reduced.

[0095]

As described above, according to the present invention, the data storage means divided into small memory blocks, the memory management means for managing the memory blocks, and the plurality of "pages" of the teletext program are managed as one file. By providing the file management means, the data compression unit, and the data decompression unit, the file access can be made flexible, and the compressed file can be freely created and the decompressed file can be deleted.
Moreover, since the efficiency of use of the memory is significantly improved, it is possible to provide an inexpensive teletext receiver and its method with about 70% of the conventional memory.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a teletext receiver according to a first embodiment of the present invention.

FIG. 2 is a memory configuration diagram showing a data storage state of a data storage unit of the embodiment.

FIG. 3 is a memory configuration diagram showing a data storage procedure in a data storage unit of the embodiment.

FIG. 4 is a block diagram showing an overall configuration of a teletext receiving device according to a second embodiment of the present invention.

FIG. 5 is a memory configuration diagram showing a data storage state of a data storage unit of the embodiment.

FIG. 6 is a memory configuration diagram showing a data storage state of a data storage unit of the embodiment.

FIG. 7 is a memory configuration diagram showing a data storage procedure in a data storage unit according to a third embodiment of the present invention.

FIG. 8 is a memory configuration diagram showing a data storage procedure in a data storage unit according to a fourth embodiment of the present invention.

FIG. 9 is a block diagram showing an overall configuration of a teletext receiving device according to a fifth embodiment of the present invention.

FIG. 10 is a block diagram showing an overall configuration of a teletext receiving device in sixth, seventh and eighth embodiments of the present invention.

FIG. 11 is a block diagram showing archive file management in the sixth embodiment of the present invention.

FIG. 12 is a block diagram showing a directory layer in file management according to a seventh embodiment of the present invention.

FIG. 13 is a block diagram showing a software configuration of a teletext receiving device according to an eighth embodiment of the present invention.

FIG. 14 is an overall configuration diagram of an example of a conventional teletext receiver.

FIG. 15 is a configuration diagram of a data storage unit of a conventional teletext receiver.

FIG. 16 is a data format diagram of a conventional teletext receiver.

FIG. 17 is a configuration diagram of a data storage unit of a conventional teletext receiver.

[Explanation of symbols]

1 CPU 2 memory 3 character signal extraction part 4 Teletext program selection section 5 Decoding section 6 Data storage 7 Memory management unit 8 File management department 9 Display memory 10 Display control unit 11 TV monitor

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Keiya Miyoshi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-1-316080 (JP, A) JP-A-4 -354284 (JP, A) JP-A-3-289889 (JP, A) JP-A-1-129679 (JP, A) JP-A-63-189080 (JP, A) Miki Kazuhiko, file management software LA RC, The BASIC, Japan, Technical Review Company, February 18, 1989, March 1989, p. 17, 22 (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04N ^7/ 00-7/088 H04N 5/38-5/46 G06F 12/00

Claims (2)

(57) [Claims] 1. A signal extraction means for receiving broadcast radio waves and extracting teletext data, and a teletext program selection means for selecting teletext data of at least one teletext program from the extracted teletext data. A data storage unit for storing the selected teletext data, and a file management unit for managing a page of the teletext data as a single file, wherein the file management unit is hierarchical in the data storage unit. Di
To have a directory structure, the channel directory is the root directory, the channel directory Broadcasting directory, the program directory by providing the page file, to accumulate the teletext program in the data storage device for each channel, A broadcast receiving apparatus comprising a file deleting unit that deletes a page file preferentially from a program directory having a plurality of page files and leaves at least one page file in the program directory when deleting files. 2. Received broadcast radio waves, extract teletext data, and select teletext data of at least one teletext program from the extracted teletext data,
The selected teletext data is stored in at least one block, pages of the stored teletext data are managed as one file, and a hierarchical directory structure is provided when the files are managed, and a root directory is provided. In the channel directory,
By storing a program directory in the channel directory and a page file in the program directory, a program of teletext is stored for each channel, and when files are deleted, the program directory having a plurality of page files is given priority to page Delete the file,
A broadcast receiving method, characterized in that at least one page file in the program directory is left.