JPH077662A - Television receiver - Google Patents

Abstract

PURPOSE:To provide a television receiver by which viewers can satisfactorily view without the sense of incongruity due to the screen display of video signals even at the time of receiving a broadcasting without the need of the screen display by the video signals such as an independent audio broadcasting using a satellite CONSTITUTION:The video signals compressed for a slave screen are obtained by using a slave screen video signal generation means 2 and a write control means 4 and are tentatively written and stored in a memory means 6 as digital signals by using an A/D conversion means 5. The slave screen video signals compressed for the slave screen are read from a digital memory 6 at a timing synchronized with a master screen by using a read control means 8 based on a clock pulse selected by a clock switching means 15. The read of the slave screen video signals by the control means 8 is controlled so as to read them as they are or to thin out and read, them, the slave screen video signals are converted into analog signals by D/A conversion means 9-11 and screen displayed by using a master/slave screen switching means 12 and the screen display for which a mosaic special effect is performed on a CRT 14 is obtained.

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 satellite broadcasting, and more particularly to a television receiver capable of displaying parent and child screens by digitizing a video signal and performing signal processing, for example, The present invention relates to a television receiver adapted to perform special image processing on an unnecessary image when receiving an independent audio broadcast or the like.

[0002]

2. Description of the Related Art In recent years, pulse modulation (Pulse Code Module) has been performed along with the multifunctionalization of television receivers.
(hereinafter, abbreviated as PCM) and has a function of receiving satellite broadcasting and a function of converting a video signal which is an analog signal into a digital signal and performing a video signal processing to display a parent-child screen. The number of television receivers that have been used is increasing.

Further, the satellite broadcasting adopting the PCM as described above has a mode in which, in addition to ordinary television sound, two independent radio broadcasting systems can be received as high-quality stereo broadcasting. Can transmit up to 4 channels of audio, so independent audio broadcasting using the rest in addition to normal TV audio has started.

On the other hand, along with the digitization of video technology, a digital television receiver for performing video signal processing using digital signals has been adopted as is well known. This digital television receiver has improved image quality by digitizing a video processing circuit. Therefore, it is possible to apply a memory to display parent-child screens, multi-screens, still images, and other screens. It is possible and has these functions.

Therefore, FIG. 3 shows a block diagram of a television receiver having a parent-child screen display function among the functions of the conventional digital television receiver as described above.

FIG. 3 is a block diagram showing an example of a conventional television receiver having a parent-child screen display function.

Generally, a television receiver having a parent-child screen display function is characterized in that a video signal of the child screen is compressed in order to insert the child screen into the parent screen and reproduced in synchronization with the parent screen. There is.

Although not shown, the received signal is converted into an intermediate frequency signal by a tuner circuit for a main screen and a tuner circuit for a child screen of the television receiver, and a video signal is amplified by a video intermediate frequency amplification and video detection circuit (not shown). Are extracted and demodulated into a luminance signal Y and color difference signals (RY, BY).

As shown in FIG. 3, the luminance signal Y and the color difference signals (RY, BY) demodulated respectively are input to the child screens 1a, 1b, 1c and the input terminal 1 for the parent screen.
They are input to d, 1e, and 1f, respectively.

The luminance signal Y and the color difference signals (RY, BY) input to the sub-screen input terminals 1a, 1b, 1c are supplied to the multiplexer 2, respectively. The multiplexer 2 performs time division processing (for example, horizontal 1/3 dot, vertical 1 / dot) based on a clock pulse signal generated by a clock generation circuit 3 and a timing signal generated by a write control circuit 4 connected to the clock pulse signal. Time division into three lines). The clock generation circuit 3 generates a clock pulse and supplies it to the write control circuit 4. Further, the write control circuit 4 generates a timing signal based on the supplied clock pulse signal and supplies the timing signal to the multiplexer 2 and also controls writing to a digital memory 6 described later.

The signal obtained by time-division processing by the multiplexer 2 is supplied to an analog / digital conversion circuit 5 (hereinafter abbreviated as A / D conversion circuit).
The / D conversion circuit 5 converts the output signal of the multiplexer 2 into a digital signal. The A / D conversion circuit 5 converts the input analog signal into a digital signal which can be represented by numerical values of "1" and "0".

The signal digitized by the A / D conversion circuit 5 is thinned out under the control of the write control circuit 4 and is written and stored in the digital memory 6.

On the other hand, the clock generation circuit 7 generates a clock pulse having a frequency about three times that of the clock generation circuit 6, and the clock pulse is read out and supplied to the control circuit 8. The read control circuit 8 reads the signal from the digital memory 6 based on this clock pulse (main horizontal / vertical synchronization), and outputs the read signal, that is, the luminance signal Y and the color difference signal (R) as digital signals. -Y, BY) are digital /
It is supplied to the analog conversion circuits 9, 10 and 11 (hereinafter abbreviated as D / A conversion circuit). D / A conversion circuits 9, 10, 11
Is for converting an input digital signal into an analog signal and outputting the analog signal. The luminance signal Y and the color difference signals (RY, BY) as the digital signals are respectively converted into analog signals to display a parent-child screen. It is supplied to the changeover switch 12.

On the parent screen side, the parent screen input terminal 1
The luminance signal Y and the color difference signals (RY, BY), which are respectively input and demodulated in d, 1e, 1f, are supplied to the parent-child screen changeover switch 12. The parent-child screen changeover switch 12 operates so as to switch between the input signal of the child screen and the input signal of the parent screen on the basis of the switching signal from the switching control 15, that is, the signal of the child screen is part of the signal of the parent screen. It is to be superposed. The superimposed output signal is supplied to the matrix circuit 13 and is output to the display unit 14 (CRT) as an RGB signal. Thereby, for example, as shown in FIG. 4, the child screen 50 combined with the parent screen 100 can be displayed on the display unit 14. As shown in FIG. 4, the image of the parent screen 100 is displayed as "A" on the screen, and the image of the child screen 50 is displayed as "B" on the screen.

By the way, when a television receiver having such a function is used to receive a broadcast whose image signal does not need to be displayed on the screen, such as an independent audio broadcast using a satellite, the same is displayed on the screen. The screen of a television program of a broadcast different from the broadcast transmitted on the channel is displayed, which causes an inconvenience that the viewer feels uncomfortable.

Therefore, in order to eliminate such inconvenience,
In order to prevent unnecessary video signals from being displayed on the screen, a television receiver equipped with a video mute function has been adopted as a conventional technology, but the mute function is still operating when this mute function is used. There is a problem that the effect is not obtained because the change on the screen is scarce when the sign indicating is displayed.

[0017]

As described above, in the conventional television receiver, when a broadcast that does not require the video signal to be displayed on the screen, such as an independent audio broadcast using a satellite, is received. There is an inconvenience that the video signal of the channel being displayed is displayed on the screen, and the viewer feels uncomfortable.

Therefore, the present invention has been made in view of the above problems. Therefore, even when a broadcast in which a video signal does not need to be displayed on the screen, such as an independent audio broadcast using a satellite, is received,
It is an object of the present invention to provide a television receiver that allows a viewer to view the image signal without feeling uncomfortable due to the screen display of the video signal.

[0019]

In the television receiver according to the present invention, a sub-screen video signal generating means, a main-screen video signal generating means, and a sub-screen video signal from the sub-screen video signal generating means are converted into digital signals. Digital converting means for converting, memory means for temporarily writing and storing the sub-picture video signal converted into a digital signal by the digital converting means, first clock generating means for generating a clock pulse, and the first Write control means for generating a timing signal based on the clock pulse generated by the clock generation means and controlling the memory means by using the timing signal, and a clock different from the clock pulse generated by the first clock generation means. Second clock generating means for generating a pulse, the first clock generating means, and When the first clock generating circuit is selected by the clock switching means and the clock switching means for selecting and switching one of the two clock generating means, a timing signal is generated based on this clock pulse. , The timing control signal is used to read out and control the sub-picture video signal written and stored in the memory means so as to be synchronized with the main picture, or when the second clock generating circuit is selected, the clock pulse A read control means for generating and controlling a timing signal based on the above-mentioned timing signal, and controlling the readout of the child screen video signal written and stored in the memory means at a cycle of 1 / n of the cycle of the parent screen. Analog conversion means for converting the sub-screen video signal read by the reading means into an analog signal, The sub-screen video signal output from the analog converting means and the main-screen video signal from the main-screen video signal generating means are input to operate in correspondence with the clock switching means, and the clock switching means provides the first signal. When the clock generation circuit is selected, it is switched to the sub-screen video signal and output to the display unit side, or when the second clock generation circuit is selected, a part of the main screen is used as a sub-screen. A parent-child screen switching unit that sequentially switches to superimpose and outputs to the display unit side, and a control unit that controls switching between the clock switching unit and the parent-child screen switching unit using a switching signal so as to correspond to each other. Is characterized by.

[0020]

In the present invention, the compressed video signal for the small screen is obtained by using the small screen image signal generation means and the writing control means, and is temporarily written in the memory means as a digital signal by the A / D conversion means. Remember. The sub-picture image signal compressed for the sub-picture stored in the memory means is read from the digital memory at a timing synchronized with the main picture by the read control means based on the clock pulse selected by the clock switching means. read out. Further, the reading control means controls the child screen video signal to be read as it is or to be further thinned out, and the child screen video signal is converted into an analog signal by the D / A conversion means, and the parent-child screen switching means. By using the to display the screen, it is possible to obtain a screen display with a mosaic-like special effect.

[0021]

EXAMPLES Examples will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a television receiver according to the present invention.

The constituent elements having the same elements as those shown in FIG. 3 are designated by the same reference numerals. The television receiver of the present embodiment shown in FIG. 1 is a television receiver having a parent-child screen display function, and in particular, a video signal of a child screen which is compressed and stored is read from a digital memory using a read control circuit. The feature is that the clock pulse at this time is switched by providing a clock switching unit.

Although not shown, the received signal is converted into an intermediate frequency signal by a tuner circuit for a main screen and a tuner circuit for a child screen of the television receiver, and a video signal is amplified by a video intermediate frequency amplification and video detection circuit (not shown). Are extracted and demodulated into a luminance signal Y and a color difference signal (RY, BY), respectively.

The luminance signal Y demodulated in this way
And the color difference signals (RY, BY) are input to the child screen input terminals 1a, 1b, 1c and the parent screen input terminals 1d, 1e, 1f, respectively, as shown in FIG.

The luminance signal Y and the color difference signals (RY, BY) input to the sub-screen input terminals 1a, 1b, 1c are supplied to the multiplexer 2, respectively. The multiplexer 2 performs time division processing (for example, horizontal 1/3 dot, vertical 1 / dot) based on a clock pulse signal generated by a clock generation circuit 3 and a timing signal generated by a write control circuit 4 connected to the clock pulse signal. Time division into three lines). The clock generation circuit 3 generates a clock pulse and supplies it to the write control circuit 4 and also to the input terminal h of the clock switching unit 15. Further, the write control circuit 4 generates a timing signal based on the supplied clock pulse signal and supplies the timing signal to the multiplexer 2 and also controls writing to a digital memory 6 described later.

A signal obtained by time division processing by the multiplexer 2 is supplied to the A / D conversion circuit 5,
The A / D conversion circuit 5 converts the output signal of the multiplexer 2 into a digital signal. The A / D conversion circuit 5 converts the input analog signal into a digital signal which can be represented by numerical values of "1" and "0".

The signal digitized by the A / D conversion circuit 5 is thinned out under the control of the write control circuit 4 and is written and stored in the digital memory 6.

On the other hand, the clock generating circuit 7 generates a clock pulse having a frequency about three times as high as that of the clock generating circuit 6, and the clock pulse is generated by the clock switching unit 1.
5 is supplied to the input terminal g. The clock switching unit 15 outputs the output of the clock generating circuit 3 and the clock generating circuit 7.
Of the input clock pulses, and supplies a clock pulse selected by a switching signal from the switching control 16 to the read control circuit 8. The read control circuit 8 generates a timing signal based on the selected clock pulse and reads a signal from the digital memory 6 in accordance with this timing, and a read signal, that is, a luminance signal Y and a color difference as a digital signal. The signals (RY, BY) are supplied to the D / A conversion circuits 9, 10, 11 respectively.

The D / A conversion circuits 9, 10 and 11 convert an input digital signal into an analog signal and output the analog signal. The luminance signal Y and the color difference signals (RY, B-) as the digital signal are output. Y) is converted into an analog signal and supplied to the parent-child screen changeover switch 12.

On the parent screen side, the parent screen input terminal 1
The luminance signal Y and the color difference signals (RY, BY), which are respectively input and demodulated in d, 1e, 1f, are supplied to the parent-child screen changeover switch 12. The parent-child screen changeover switch 12 performs a switching operation between the input signal of the child screen and the input signal of the parent screen based on the switching signal from the switching control 16, and superimposes the signal of the child screen on a part of the signal of the parent screen. It is a thing. This superimposed output signal is supplied to the matrix circuit 13 and is displayed as an RGB signal on the display unit 1.
4 (CRT), and the parent-child screen table is displayed on the display unit 14. The switching control 16 includes the clock switching unit 15 and the parent-child screen switching switch 12
Is controlled by a switching signal, and the switching operation between the clock switching unit 15 and the parent-child screen switching switch 12 is made to correspond.

Next, the operation of the thus-configured television receiver will be described in detail with reference to FIG.

FIG. 2 shows an example of an output screen of the television receiver shown in FIG. 1, FIG. 2 (a) shows a screen in which images are displayed in a mosaic pattern, and FIG. 2 (b) shows FIG. 2 (a). 3 shows a screen image-displayed in a special shape different from.

First, when the input terminal h is selected by the clock switching unit 15 as shown in FIG. 1, the luminance signal Y and the color difference signal (RY) input to the sub-screen input terminals 1a, 1b, 1c are first selected. , BY) is time-division-processed by using the multiplexer 2 in accordance with the timing signal generated by the write control circuit 4 based on the clock pulse signal generated from the clock generation circuit 3 (for example, horizontal 1/3).
Dot and vertical are time-divided into 1/3 line).

Next, the signal obtained by the time division processing by the multiplexer 2 is supplied to the A / D conversion circuit 5, and the output signal of the multiplexer 2 is converted into a digital signal by the A / D conversion circuit 5. To do.

Then, the signal digitized by the A / D conversion circuit 5 is thinned out under the control of the write control circuit 4, and is written and stored in the digital memory 6.

On the other hand, the output terminal of the clock generation circuit 3 is in the ON state with the read control circuit 8 because the clock switching section 15 is switched by the switching signal of the switching control circuit 16. Therefore, the clock pulse generated by the clock generation circuit 3 is supplied to the read control circuit 8.

The read control circuit 8 generates a timing signal based on the clock pulse of the selected clock generation circuit 3 and reads the signal from the digital memory 6 at this timing, and the read signal, that is, the digital signal. The luminance signal Y and the color difference signals (RY, BY) are supplied to the D / A conversion circuits 9, 10 and 11, respectively. That is, the reading by the reading control circuit 8 has the same cycle as the video signal of the child screen written and stored in the digital memory 6, and the horizontal and vertical reading is performed at the same cycle as the parent screen. Become. Further, in this reading step, the luminance signal Y and the color difference signals (RY, BY) are read by the timing signal from the read control circuit 8 so as to further thin out the signals. In other words, this is performed to obtain a special effect, and the mosaic special effect is addressed.

Then, the luminance signal Y of the read child screen is displayed.
And the color difference signals (RY, BY) are D / A conversion circuit 9,
D / A conversion is performed using 10 and 11 to convert into an analog signal.

After that, the signal converted into the analog signal is supplied to the parent-child screen changeover switch 12 and inputted to the parent screen luminance signal Y and color difference signals (RY, B-).
Y). In this case, the parent / child screen changeover switch 12 is controlled to be changed over to the small screen side by the changeover signal of the changeover control 16.

As a result, in the matrix circuit 13, R
After being converted into a GB signal, the display unit 14 can display an image having a special effect as shown in FIG. 2A or 2B on the entire screen.

Further, when implementing a normal parent-child screen, the switching of the clock switching unit 15 may be switched to the input terminal g so that the clock generation circuit 7 is turned on by using the switching control 16. Further, the operation when switched in this way is the same as the operation described in FIG. 3, and a description thereof will be omitted.

Therefore, in the present embodiment, a television receiver having a parent-child screen display function is used, and the compressed data for displaying the child screen is written in the digital memory 6.
Then, when the sub-picture video signal written in the digital memory 6 is read, the clock switching circuit 15 switches to the clock generation circuit 3 so that the reading control circuit 8 is used to perform the same horizontal and vertical operations as the parent screen. The sub-screen video signal can be read in synchronization with. Also,
The sub-screen video signal is read by using the timing signal of the read control circuit 8 so as to be further thinned out at the time of reading, and is converted into an analog signal by the D / A conversion circuits 9, 10, 11.

Then, the sub-picture video signal is superimposed on the main-picture video signal by using the parent-child picture changeover switch 12, so that the display section 14 is formed by using the matrix circuit 13.
For example, a special effect of displaying a mosaic image on the screen can be applied to the (CRT).

In this embodiment, one A / D conversion circuit is used, but a plurality of A / D conversion circuits may be provided so as to correspond to respective signals.

Further, in the present embodiment, the reading of the sub-picture video signal for obtaining the special effect is described to be controlled at the time of reading by using the reading control circuit. However, this control is not performed at the time of reading, and D / This is performed at the time of A conversion, for example, for the luminance signal only, the lower bits are forced to 0.
Alternatively, it may be set to 1 to obtain a special effect of solarization such as an oil painting.

[0046]

As described above, according to the present invention, in the case of receiving a broadcast which does not need to display a video signal on the screen, such as an independent audio broadcast using a satellite, an image of this video signal can be displayed easily. An image with a mosaic-like special effect can be displayed on the screen by the configuration, and the viewer can listen to it without any discomfort.

Further, the present invention can be easily implemented with the simple structure as described above, and it is needless to say that the effect can be obtained at a low cost.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a television receiver according to the present invention.

FIG. 2 is a screen display diagram showing an output screen of the television receiver shown in FIG. 1 and subjected to image processing.

FIG. 3 is a block diagram showing a conventional television receiver having a parent-child screen display function.

FIG. 4 is a screen display diagram showing an example of an output screen of a television receiver having a parent-child screen function.

[Explanation of symbols]

 1a, 1b, 1c ... Child screen video signal input terminals 1d, 1e, 1g ... Parent screen video signal input terminal 2 ... Multiplexer (MPX) 3 ... Clock generation circuit (CK1) 4 ... Write control circuit 5 ... A / D conversion circuit 6 ... Digital memory 7 ... Clock generation circuit (CK2) 8 ... Read control circuit 9, 10, 11 ... D / A conversion circuit 12 ... Parent-child screen changeover switch 13 ... Matrix circuit 14 ... Display unit (CRT) 15 ... Clock changeover unit 16 ... Switching control

Claims (1)

[Claims] 1. A sub-screen video signal generating means, a main-screen video signal generating means, a digital converting means for converting the sub-screen video signal from the sub-screen video signal generating means into a digital signal, and a digital signal by the digital converting means. Memory means for temporarily writing and storing the sub-picture video signal converted into a signal, first clock generating means for generating a clock pulse, and based on the clock pulse generated by the first clock generating means Write control means for generating a timing signal and controlling the memory means by using the timing signal; second clock generating means for generating a clock pulse different from the clock pulse by the first clock generating means; Either the first clock generating means or the second clock generating means is selected. And a clock switching unit for switching the first clock generation circuit by the clock switching unit to generate a timing signal based on the clock pulse and write the timing signal to the memory unit using the timing signal. The stored sub-picture video signal is read out and controlled so as to be synchronized with the main picture, or when the second clock generation circuit is selected, a timing signal is generated based on this clock pulse, and the timing signal is generated. A read-out control means for controlling the read-out of the sub-picture video signal written and stored in the memory means at a cycle of 1 / n of the cycle of the main screen, and the sub-picture video read by the reading means. Analog conversion means for converting the signal into an analog signal, and a sub-screen image signal output from the analog conversion means. And a parent screen video signal from the parent screen video signal generating means are input to operate in correspondence with the clock switching means and when the clock switching means selects the first clock generating circuit. , And outputs to the display unit side after switching to the sub-screen video signal, or when the second clock generation circuit is selected, sequentially switches to the display unit side so as to be superimposed as a sub-screen on a part of the main screen. A television receiver comprising: a parent-child screen switching unit for outputting; and a control unit for controlling switching between the clock switching unit and the parent-child screen switching unit using a switching signal so as to correspond to each other.