JPH01143579A - Teletext receiver - Google Patents

Abstract

PURPOSE:To display a text signal at a requested time by extracting and recording a text signal of a TV video signal over one or plural channels even when an external video signal is being displayed. CONSTITUTION:At first a program reservation list of a teletext broadcast is formed and recorded in a nonvolatile memory 21. When a recording key (b) of an operation section 16 is depressed while an external video signal is being displayed, a video changeover circuit 9A outputs a TV video signal. A synchronizing separator circuit 13 applies synchronizing separation to the video signal and outputs the result to an extraction circuit 14 to extract part of the text signal and stores it to a buffer memory A15. A control circuit 17 analyzes the content of the memory 15 according to the program reservation, and records it sequentially in a buffer memory 18B when the content is coincident. In the case of observing text information, the circuit 17 reads the data in the memory 18B by the command of an operation section 16, applies decode processing and accesses a KANJI ROM 22 and a display memory 20 through a display control circuit 19 to reproduce the text information.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a teletext receiving device that receives and displays teletext.

BACKGROUND OF THE INVENTION Nowadays, code-based teletext broadcasting has been put into practical use, and decoders have shifted from adapter-type decoders to ones built into television sets. Furthermore, since television receivers are also AV compatible, those with video input terminals are becoming popular. Furthermore, the spread of VTRs with tuners is remarkable.

The conventional teletext receiving apparatus as described above will be described below with reference to screens.

FIG. 4 shows a block diagram of a conventional teletext receiver. In FIG. 4, 31 is an antenna, 32 is a tuner, 33 is an intermediate frequency amplification circuit, 34 is a detection circuit, 3
5 is a video switching circuit, 36 is a video processing block, 37 is an operating section, 38 is a character signal reproduction block, 39 is a cathode ray tube, and 40 is a video input terminal. Further, 37a is a TV/video changeover switch.

The operation of the teletext receiving apparatus configured as described above will be described below.

The RF multiplied signal received from the antenna 31 is converted into an intermediate frequency signal by the tuner 32, amplified by the intermediate frequency amplification circuit 33, and reproduced as a video signal by the detection circuit 34. The video signal switching circuit 35 switches between the video signal reproduced by the detection circuit 34 and the video input signal from the video input terminal 40, and sends the video signal for display to the video processing block 36.

The video processing block 36 processes the video signal and displays it on the cathode ray tube 39. On the other hand, the video signal reproduced by the detection circuit 34 is decoded by a character signal reproduction block 38 to create RGB signals and the like and output them to the video processing block 36. In addition to the processing described above, the video processing block 36 also performs text information display processing.

If the switch a in the operation unit 37 is set to the TV side, the character signal reproduction block 38 converts the character multiplex signal in the video signal in order to quickly respond to the character information display operation of the operation unit 37. Decryption processing is in progress.

However, when switch a in the operation unit 37 is set to the video side, conventional teletext receiving apparatuses do not perform decoding processing. Furthermore, when viewing a teletext broadcast on multiple channels while displaying a video signal on the TV side, it was necessary to change the channel.

Problems to be Solved by the Invention However, the above method has a problem in that the function as a teletext receiving device is stopped when the video from the external video input terminal 40 is being viewed. was.

In view of the above-mentioned problems, the present invention extracts the character multiplex signal included in the TV video signal and sequentially records it in the memory even when the video signal from the external video input terminal is displayed. The present invention provides a teletext receiving apparatus which can sequentially search according to the registered content, record it in the memory, and display it when necessary, by registering the program number and program number.

Means for Solving the Problems To achieve this object, the teletext receiving apparatus of the present invention includes a tuner, an intermediate frequency amplification circuit, a detection circuit, a first . Second
The video switching circuit is equipped with a 2-character signal extraction circuit, a memory, a control circuit, etc., and switches between a video signal obtained from a tuner etc. and a video signal from an external video input terminal, and displays one of them. It is constructed so that the character multiplex signal from the video signal that is not displayed is extracted and recorded in the memory.

Operation With this configuration, while the video signal reproduced by the tuner, intermediate frequency amplification circuit, and detection circuit and the video signal from the external video input terminal are being switched and displayed by the first video switching circuit, the above-mentioned two By adding different types of video signals to the second video switching circuit, taking out the video signal that is not being displayed, and adding it to the character signal sampling circuit, only the necessary character signals can be sequentially recorded in the memory by the control circuit.

EXAMPLE An example of the present invention will be described below with reference to the drawings. FIG. 1 shows a block diagram of a teletext receiver according to an embodiment of the present invention. In FIG. 1, 31 is an antenna, 32 is a tuner, 33 is an intermediate frequency amplification circuit, 34 is a detection circuit, 39 is a cathode ray tube, and 40 is a video input terminal, which is the same as the configuration shown in FIG. 3.

A video switching circuit B 5 switches between an external video signal and a television video signal. 6 is an RGB reproduction circuit that converts the video signal into an RGB signal. 7 is synchronous separation circuit B, 8
The RGB switching circuit switches between displaying a video signal and character information using RGB. 9 is a video switching circuit A that switches between an external video signal and a television video signal, and outputs the signal to a character signal reproduction block 38. Reference numeral 1o denotes a channel selection circuit which outputs channel variable instructions based on commands from the control circuit 17. Reference numeral 11 denotes a synchronization switching circuit which switches between a synchronization signal for displaying a video signal and a synchronization signal for displaying character information and outputs the same to the deflection circuit 12. 13 is a synchronous separation circuit A which synchronously separates the video signal from the video switching circuit 9A. Reference numeral 14 denotes a sampling circuit which extracts the character multiplexed signal multiplexed during the vertical blanking period and reproduces the clock and data. A buffer memory A 15 temporarily records the character multiplex signal output from the sampling circuit 14. Reference numeral 16 denotes an operation section which gives operation instructions to the control circuit 17. The control circuit 17 controls the video switching instruction 1 display control circuit, controls the memory, and so on. A buffer memory B 18 records only necessary signals among the character multiplexed signals temporarily recorded in the buffer memory A. A display control circuit 19 controls the display memory 20 and reproduces signals such as RGB. 21 is a non-volatile memory that is rewritable□ RO
I'm using M. 22 is a kanji ROM.

The b key on the operation unit 16 is the "record" key.

The operation of the teletext receiving apparatus configured as described above will be described below. First, as shown in FIG. 2, a teletext program reservation table is created. Up to eight programs can be reserved, and the channel, teletext magazine, pangumi, title, etc. can be set for each program. After the program reservation table is created, it is recorded in the nonvolatile memory 21, and its contents are retained even when the power is turned off. In addition, as shown in FIG. 3, the video input setting screen is displayed, and the video switching circuit 9
Determine whether the output of A is a TV video signal or an external video signal. If you select "1. Auto" here, while recording the character signal,
The video signal not displayed on the cathode ray tube is output from the video switching circuit 9A. Also '2. When TVJ is selected, the video switching circuit 9 outputs the video signal reproduced on the TV.

Also, when "3. External video input" is selected, the external video input signal is output. Video input settings are also recorded in the nonvolatile memory 21, and the contents are retained even when the power is turned off.

If the video input setting is "1. Auto", blanking 39
When the record key b of the operation unit 16 is pressed while the external video signal is being displayed, the video switching circuit 9A outputs the TV video signal. The synchronization separation circuit 13 synchronizes and separates the video signal, and generates a horizontal synchronization signal, a vertical synchronization signal, and a gate signal indicating the multiplex period of two teletext broadcasts (only during the 10th horizontal scanning period to the 21st horizontal scanning period of the vertical blanking period). rH
” level or “L” level signal) is extracted from the circuit 1.
4, the text multiplex signal portion is extracted from the video signal, the binary clock and data are reproduced and temporarily recorded in the buffer memory 15. The control circuit 17 analyzes the contents of the buffer memory 15A in accordance with the program reservation shown in FIG. 2, and if the packet data matches the program, it sequentially records it in the buffer memory 18B. Since the contents of the buffer memory 15A change for each field, if the operations are repeated in sequence, packets for all pages of the program will be recorded. Thereafter, if there is the same channel among Arashi 1 to 8 in FIG. 2, the packet data of the program is preferentially recorded in the buffer memory 18. When data collection for reserved programs on the same channel is completed in this way, a storm on a different channel is found starting from the smaller storm, and the same operation as described above is performed. Taking FIG. 2 as an example, since two channels of programs are reserved for teeth 1 to 3, the packet data of all pages of 10 programs, 100 programs, and 200 programs are sequentially stored in the buffer memory 18B. to be recorded.

11h4 after the end. Nb2. Change the channel to 4 channels of &6 (send data from the control circuit 17 to the channel selection circuit 10, and change the reserved programs 300, 4 in the same way as above)
Packet data for all pages of 00.500 are recorded in the buffer memory 18B. Arashi 7 and Arashi 8 perform similar operations, and when all packet collection is completed, the control circuit 17 switches the output of the video switching circuit 9A to the video signal currently being displayed, and also instructs the display control circuit 19 to display. is given, a message indicating the end of the program reservation is recorded in the display memory 20, and the display control circuit 19 outputs the signal to the RGB switching circuit 8 which converts it into a KGB signal and displays it in a superimposed manner.

When viewing character information, the control circuit 17 reads out the packet data from the buffer memory 18B in response to an instruction from the operation unit 16, decodes it, and passes it through the display control circuit 19 to the kanji ROM 22. Display memory 20 is accessed to reproduce character information. The reproduced character information is R, G
, B, and is output to the RGB switching circuit 8, and also outputs a synchronization signal to the synchronization switching circuit 11,
Display text information.

As described above, according to this embodiment, when an external video signal is displayed on a cathode ray tube, by recording the character multiplex signal in the video signal created by the TV, the character information spanning between channels can also be saved without waiting time. You can see it without even realizing it. Also, at this time, V with a tuner is used as an external video signal.
If you use TR, you can get the text information you want while watching the same channel.

In this embodiment, the character information was retrieved by making a reservation as shown in Fig. 2, but when viewing the external video signal, the T.
It is also easy to record character information for a fixed period of time by changing the V channel, or to record text information for a fixed period of time by automatically changing the channels one after another.

Effects of the Invention As described above, the present invention provides a tuner, an external video input terminal,
By using the control circuit 2 character signal extraction circuit, memory, etc., even when an external video signal is displayed, character signals of the TV video signal can be extracted and recorded over one or more channels and displayed when necessary. , its practical effects are great.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a block diagram showing a teletext receiver according to an embodiment of the present invention, Fig. 2 is a front view of a screen showing an example of program reservation, and Fig. 3 is a block diagram showing a teletext receiving device according to an embodiment of the present invention. FIG. 4 is a front view of a screen showing an example, and a block diagram showing an example of a conventional example. 5.9...Video switching circuit, 10...Tuning selection circuit, 14...Character signal sampling circuit, 15.
18...Buffer memory, 16...Operation unit, 17...Control circuit, 9...Display control circuit, 20...Display memory, 21・・・・・・
Non-volatile memory, 32... Tuner, 39...
...Cathode ray tube. Name of agent: Patent attorney Toshio Nakao and one other person Figure 2 Figure 3

Claims (2)

[Claims] (1) When switching between the video signal reproduced by a tuner, intermediate frequency amplification circuit, detection circuit, etc. and the video signal input from the external video input terminal, and displaying either one, the display is not displayed. means for extracting and sequentially recording the character multiplexed signal of the video signal of the video signal, means for extracting and sequentially recording the character multiplexed signal from the video signal being displayed, and means for switching between the two means. A teletext receiving device characterized by comprising: (2) When a video signal from an external video input terminal is displayed, the channel, program, etc. that you want to reserve is recorded in advance in memory, and based on that, the character multiplex signal is extracted and sequentially recorded in memory. A teletext receiving device according to claim 1.