JPH05252492A - Multi display television receiver - Google Patents

Abstract

PURPOSE:To provide a TV receiver capable of multi display by displaying TV programs by means of one tuner and efficiently collecting character data included in the teletext broadcasting of the other channel. CONSTITUTION:A video signal processing circuit 5 extracts the horizontal scanning lines comprising TV video signals to perform the picture compression. During the scanning period of the horizontal scanning lines not to be extracted, a tuner 2 is switched to receive the teletext broadcasting and fetching character data included in the broadcasting in a teletext multiplex broadcasting processing circuit 8. A multi display control section 9 changes a horizontal scanning line to be extraction object for each field, and a group of character data collected by the circuit 8 is multi-displayed on a CRT 71 by means of a display signal switching circuit 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver capable of receiving a character multiplex broadcast, and more particularly, it displays an image of a television broadcast of an arbitrary channel in a reduced size and at the same time displays another image on the same screen. The present invention relates to a multi-display television receiver capable of displaying character data included in character multiplex broadcasting of a channel.

[0002]

2. Description of the Related Art In character multiplex broadcasting, as shown in FIG. 7, character data is multiplexed using a 4H period in a vertical blanking interval, and during the reception of television broadcasting, character multiplex of the same channel is performed. It is possible to capture broadcast character data and display it on the screen.

By the way, one means for easily making a recording reservation, such as the VPT method (Video Programming by TELETEXT) using text multiplex broadcasting in West Germany (see Sanyo Denki Giho Vol.22 No.1 Feb.1990). As a method, a program guide is displayed on a television receiver (hereinafter referred to as a TV), and a desired program is selected from the displayed program guide by a cursor or the like to store the recording reservation information of the program in the VTR main body. It has been known.

[0004]

However, in the case of creating a program table of character multiplex broadcasting over a plurality of channels,
It is necessary to switch the reception frequency of the tuner, sequentially receive the character multiplex broadcasting of each channel, and collect the program data for all the character multiplex broadcasting, which not only requires a long time, There was a problem that the TV broadcast program could not be viewed during the collection of the program data.

If a plurality of tuners are provided, one tuner collects program data for character multiplex broadcasting,
Although it is possible to receive and display TV broadcast by another tuner, the configuration of the TV receiver becomes complicated.

An object of the present invention is to display a TV broadcast program on a screen by a single tuner, efficiently collect character data included in a character multiplex broadcast of another channel, and display the character data on the same screen. An object of the present invention is to provide a multi-display TV receiver capable of displaying characters of multiple broadcasts.

[0007]

Multi-display T according to the present invention
The V receiver includes video signal processing means for intermittently extracting horizontal scanning lines forming a TV video signal to perform vertical image compression, and video signal processing during display of a compressed image by the video signal processing means. The character data processing means for switching to the receiving operation of the character multiplex broadcasting of another channel and capturing the character data included in the character multiplex broadcasting only during the scanning period of the horizontal scanning line which is not the extraction target by the means, and the video signal processing means. Extraction control means for changing the horizontal scanning line to be extracted for each field or for each frame, and a group of character data fetched by the character data processing means is displayed on the display screen of the compressed image. And display control means.

[0008]

In general, the TV broadcast video signals of different channels are out of phase with each other, and when the difference Δt between them is very small as shown in FIG. 5, the vertical direction of the TV broadcast video signal of the channel CHa being received. During the blanking period, even if the tuner is switched to another channel, it does not hinder the reception of the video signal of the TV broadcast, so that the character data included in the vertical blanking period of the TV broadcast of the other channel CHb can be obtained. Can be captured.

However, when the deviation Δt becomes large as shown in FIG. 6 and the period of the TV video signal of the channel CHa and the vertical retrace period of the channel CHb overlap, the tuner cannot be switched.

Therefore, according to the present invention, when a character broadcast of another channel is received and displayed on the same screen while receiving and displaying the TV broadcast, the image of the TV broadcast of the channel CHa is reduced and displayed as shown in FIG. By doing so, the tuner can be switched and the character data contained in the channel CHb is displayed on the same screen.

That is, the video signal processing means extracts only one horizontal scanning line for every three consecutive horizontal scanning lines, and compresses the image in the vertical direction by a factor of 3 to display the image. is there. In this case, during the scanning period of the two horizontal scanning lines that are not to be extracted, the TV that is receiving even if the tuner is switched
There is no problem in displaying the video signal of broadcasting.

Therefore, the character data processing means can fetch the character data included in the character multiplex broadcasting by switching to the receiving operation of the character multiplex broadcasting of another channel only during the scanning period of the horizontal scanning line which is not the extraction target. It is possible.

However, in the data fetching operation only for the scanning period of a certain horizontal scanning line which is not the extraction target, it is not possible to fetch all the character data of 4H included in the vertical blanking period. , The horizontal scanning line to be extracted is changed for each field or for each frame, and the scanning period of the horizontal scanning line which is not to be extracted,
That is, the data acquisition timing is gradually shifted so that all the character data are efficiently acquired in the minimum required plural field period.

The group of character data thus fetched is displayed at an appropriate position on the screen by the display control means.

[0015]

According to the multi-TV receiver of the present invention, a single tuner receives a TV broadcast of an arbitrary channel and displays it in a reduced size on the screen without causing any trouble in the display. It is possible to efficiently capture the character data included in the character multiplex broadcast of another channel and display the character data in multi on the same screen.

[0016]

EXAMPLE An example of the present invention will be described in detail below.
In the present embodiment, the image of the TV broadcast program of the arbitrary channel CHa is vertically reduced to one-third and displayed, and at the same time, the character data included in the character multiplex broadcast of the other channel CHb is displayed on the same screen. Shall be displayed. The image is also reduced in the same ratio in the horizontal direction, but since this processing is publicly known, description thereof will be omitted.

FIG. 1 shows the configuration of a multi-display TV receiver according to the present invention. The broadcast signal captured by the antenna (1) is received and selected by the tuner (2) and the detection circuit (3) is selected. Is sent to the vertical synchronization phase detection circuit (4).

The vertical synchronization phase detection circuit (4) generates a reference clock as shown in FIG. 3 in one field cycle, and the reference clock and two channels CH to be multi-displayed.
The phase difference .phi.a and .phi.b between a and CHb of the vertical synchronizing signal Vs is detected, and the deviation .DELTA.t between the two phase differences is detected.

Channel C on which the TV broadcast image should be displayed
The received signal of Ha is once taken into the dual port memory (6) by the video signal processing circuit (5) shown in FIG. 1 and then subjected to signal processing and supplied to the display signal switching circuit (7).

On the other hand, the received signal of the channel CHb of the character multiplex broadcasting for displaying the character data is the video signal processing circuit.
After passing through (51), it is sent to a character multiplex broadcast processing circuit (8) including a memory (not shown), and character data is extracted. The character data is supplied to the display signal switching circuit (7).

The display signal switching circuit (7) switches the TV broadcast video signal from the video signal processing circuit (5) and the character data video signal from the video signal processing circuit (51) at an appropriate timing. , CRT (71). As a result, the TV broadcast program of the channel CHa and the character data of the character multiplex broadcast of the channel CHb are multi-displayed on one screen as shown in FIG.

Tuner (2), vertical sync phase detection circuit
A multi-display control unit (9) consisting of a microcomputer is connected to the video signal processing circuits (5) and (51) and the display signal switching circuit (7) via a control bus. , The channels CHa and CHb are switched, and the circuit operations such as detection of the vertical synchronization phase differences φa and φb and the phase difference deviation Δt are controlled.

The multi-display processing by the TV receiver shown in FIG. 1 will be described below with reference to the flow chart shown in FIG.

First, after the deviation Δt of the vertical synchronization phase difference between the TV broadcasts of the channels CHa and CHb is detected (S1), the character data of the channel CHb is changed to the vertical blanking period of the channel CHa according to the value of the deviation Δt. It is determined whether or not it exists inside (S2). As shown in FIG. 5, Δt≈0, and CH
When the character data of CHb can be received within the vertical blanking period of a, the character data can be taken in by tuning the tuner to CHb during the vertical blanking period of CHa.

Therefore, as shown in FIG. 2, first, the tuner is tuned to CHb to fetch the character data (S3), and then the tuner is tuned to CHa to fetch the video data (S4).

On the other hand, if Δt is larger than the predetermined value as shown in FIG. 6 and the character data of CHb cannot be received within the vertical blanking period of CHa, steps S5 to S7 of FIG. 2 are repeated. That is, in the first field period, as shown by the solid line arrow in FIG. 4, after the video data of the first horizontal scanning line L1 is fetched, the tuner is set in the next second horizontal scanning period and third horizontal scanning period. Is tuned to CHb and the first 1H
The minute character data D1 is fetched. Next, change the tuner to CHa
The video data of the fourth horizontal scanning line L1 'is fetched, and thereafter, the horizontal scanning lines are intermittently extracted at a ratio of one to three, and the video data for one screen is fetched.

In the next field period, as shown by the broken line arrow in FIG. 4, after the video data of the second horizontal scanning line L2 is taken in, the next third horizontal scanning period and the fourth horizontal scanning period are performed. The tuner is tuned to CHb and the second 1
The character data D2 for H is fetched. Then CH the tuner
The video data of the fifth horizontal scanning line L2 'is fetched in synchronism with "a", and thereafter, the horizontal scanning lines are extracted at a ratio of one to three, and the video data for one screen is fetched.

Further, in the next field period, after the video data of the third horizontal scanning line L3 is taken in, as shown by the chain line arrow in FIG. 4, in the next fourth horizontal scanning period and fifth horizontal scanning period. The tuner is tuned to CHb and the third 1H
The minute character data D3 is fetched. Next, change the tuner to CHa
The video data of the sixth horizontal scanning line L3 'is fetched in synchronism with, and thereafter, the horizontal scanning lines are extracted at a ratio of one to three, and the video data for one screen is fetched.

The fourth 1H character data D4 can also be fetched by the same procedure.

When a group of character data to be displayed on the screen is accumulated by repeating the procedure of S5 to S7 of FIG. 2, the channel CHb is displayed on the video display screen of the channel CHa as shown in FIG. The character data of is displayed in multi.

According to the multi-display TV receiver, one tuner receives a TV broadcast, and while displaying it in a reduced size, a character multiplex broadcast of a channel different from the TV broadcast is received to capture character data. This enables the multi-display of TV broadcast programs and teletext data.

The above description of the embodiments is for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope. The configuration of each part of the present invention is not limited to the above embodiment, and it is needless to say that various modifications can be made within the technical scope described in the claims.

For example, by equipping each of the tuner and the dual port memory with each other, the sub-screen of the TV broadcast of another channel is displayed on the main screen of the TV broadcast, and the character multiplex broadcast data is multi-displayed on the main screen. It is also possible to display. In this case, as the reference clock shown in FIG. 3, it is possible to use the vertical synchronizing signal of the video signal that constitutes the parent screen.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a multi-display TV receiver according to the present invention.

FIG. 2 is a flowchart showing the operation of the multi-display TV receiver according to the present invention.

FIG. 3 is a timing chart illustrating a method of detecting a deviation of vertical synchronization signals of video signals of different channels.

FIG. 4 is a waveform diagram for explaining capture timing of character data.

FIG. 5 is a waveform diagram of both video signals when the deviation of the vertical synchronization signals of the video signals of different channels is small.

FIG. 6 is a waveform diagram of both video signals when there is a large deviation between the vertical synchronization signals of the video signals of different channels.

FIG. 7 is a waveform diagram showing a multiplexing position of character data in the character multiplex broadcasting.

FIG. 8 is a diagram showing a multi-display screen.

[Explanation of symbols]

 (2) Tuner (4) Vertical sync phase detection circuit (7) Display signal switching circuit (9) Multi-display control section

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 18, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 4

[Correction method] Change

[Correction content]

FIG. 4 is a waveform diagram illustrating a timing for capturing character data.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Yamada 2-18 Keihan Hondori, Moriguchi City, Osaka Prefecture Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. A television receiver capable of capturing character data included in a character multiplex broadcast, which is superimposed on a vertical blanking period of a television video signal, and reduces an image of a television broadcast of an arbitrary channel. It is a multi-display television receiver that can display the character data included in the character multiplex broadcasting of other channels on the same screen at the same time, and intermittently extracts the horizontal scanning lines that compose the television video signal. And a video signal processing means for vertically compressing the image, and during the displaying of the compressed image by the video signal processing means, the reception of the character multiplex broadcast during the scanning period of the horizontal scanning line which is not the extraction target by the video signal processing means. A character data processing means for switching the operation to take in the character data included in the character multiplex broadcasting, and the video signal processing means. Extraction control means for changing the horizontal scanning line to be extracted for each field or for each frame, and a group of character data taken in by the character data processing means is displayed on the display screen of the compressed image. A multi-display television receiver comprising display control means.