JPS6127256Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a television receiver and aims to provide one that is easy and convenient to use.

It has been considered that various types of information can be transmitted by using television signals and superimposing multiplexed signals during the vertical retrace period, and one example is the transmission of still image information of characters and graphics. The following still image transmission system has been considered. This invention will be explained below using this system as an example.

In this system, a page of still images to be transmitted is transmitted over 200 horizontal television lines (or
208) consists of lines, and each line is
As shown in the figure, each picture element consists of 245 bits. Furthermore, when transmitting a character image, one page of character image consists of 8 lines, and each line is
It consists of 26 lines each. When transmitting a graphic image, all 208 lines are used; when transmitting a character image, the upper 18 lines of each line are used for the character pattern, and the lower 8 lines of each line are used as interline spaces.

The following description will be made assuming that such a character image is transmitted.

Then, on the transmitting side, such a character image is scanned in the horizontal direction sequentially from the upper line as shown by the dashed line in FIG. 1A, and an image signal V for each line as shown in FIG. Obtain a binary signal of
As shown in C and D of the same figure, this is multiplexed by superimposing one line at any horizontal period during the vertical retrace period of the television signal, for example, the 20th H (odd field) and the 283rd H (even field). and send it.

At the same time, an 8-bit (4 cycle) start signal indicates the reference phase and reference amplitude of all signals.
STX, a 4-bit program code signal PC indicating which program the image signal V belongs to,
A code signal such as an 8-bit line number code signal LN indicating which line from the top of the image the image signal V belongs to is also superimposed, multiplexed, and transmitted as an information signal.

An 8-bit framing code signal (for example, a fixed signal of "11100101") FC indicating that the signal is a still image signal may be inserted next to the start signal STX.

The image signal V is multiplexed in the above manner starting from the upper line of the character image at a rate of one line per field, and one line of one program is multiplexed.
Image signals for pages are continuously superimposed.

However, as shown above, one page of still images can be
In the field immediately before transmitting the image signal V of each row divided into rows, the image signal V is not superimposed, but instead a row code signal indicating which row it is and a color code signal indicating the display color of that row. The image signals V for one row are transmitted continuously from the next field. The row code signal is distinguished from the line number code signal LN by using "225" to "232", which are never used as the line number code signal LN, as code signals representing the 1st to 8th rows, respectively. The superimposition position is the position of the line number code signal LN. Further, the color code signal is superimposed on the first half of the superimposition position of the image signal V, and the color to be displayed for each character in the row is instructed by a code signal of 3 bits per character.

In addition, in order to transmit a wide variety of images such as news and weather forecasts, it is necessary to increase the number of programs.
For example, 10 programs are transmitted. In that case, for each program, one page worth of still image signals is continuously transmitted across 208 fields as described above, but when transmitting 10 programs, such one continuous program is transmitted continuously. As a unit, still image signals for 10 programs "A", "B", .

A television receiver according to an embodiment of this invention which can display still images transmitted by such a still image transmission system and which can receive and process multiple audio signals is shown in FIGS. 2 to 5. That is, as shown in FIG. 2, this television receiver includes a tuner circuit 1, a video intermediate frequency amplification circuit 2, a video detection circuit 3, a signal processing/deflection circuit 4, a signal switching circuit 5, and a color cathode ray tube 6. , audio intermediate frequency amplification circuit 7, audio detection circuit 8, audio multiplex demodulation circuit 9, audio signal selector 10, speaker 11, audio output terminal 12, character signal receiving circuit 13, character signal selector 14, video output terminal 15, tuner circuit 16, video intermediate frequency amplification circuit 17, video detection circuit 18, signal switching circuit 19, signal processing/deflection circuit 20, monochrome cathode ray tube 21, and image selector 2
It is composed of 2. In this case, the video intermediate frequency amplification circuit 2 extracts the character signal superimposed and sent during the vertical retrace period, that is, it passes the high-frequency components of the character signal and generates less amplitude distortion and phase distortion. In order to obtain a waveform, the bandwidth is set at the upper limit of the video signal component output from the tuner circuit 1, that is, around 4.2 MHz. The video detection circuit 3 is a circuit that detects the output of the video intermediate frequency amplification circuit 2. The signal processing/deflection circuit 4 includes a comb filter that removes color subcarrier components from the output of the video detection circuit 3, a processing circuit that processes luminance signals and color signals, and a deflection circuit. If the output of the signal processing/deflection circuit 4 is supplied to the color cathode ray tube 6 through the circuit 5, a color image of a normal program can be displayed. The audio intermediate frequency amplification circuit 7 uses a separate carrier system, and the output of the tuner circuit 1 is added thereto.
The audio detection circuit 8 detects the output of the audio intermediate frequency amplification circuit 7 and outputs a multiplexed audio signal. The audio multiplexing and demodulating circuit 9 separates the multiplexed audio signal output from the audio detection circuit 8 into a main audio signal and a sub audio signal. The audio signal selector 10 is an audio multiplex demodulation circuit 9
This is a switch that switches the audio signal output from the main audio signal to the speaker 11 into a main audio signal or a sub audio signal. The audio output terminal 12 outputs the main audio signal and the sub audio signal that are not output to the speaker 11. Character signal receiving circuit 13 and character signal selector 14 will be explained in connection with FIGS. 3 and 4, respectively. The video output terminal 15 is a terminal for taking out a video signal from the character signal receiving circuit 13. The tuner circuit 16, the video intermediate frequency amplification circuit 17, and the video detection circuit 18 are similar to the tuner circuit 1, the video intermediate frequency amplification circuit 2, and the video detection circuit 3, respectively. The signal switching circuit 19 will be explained in connection with FIG. The signal processing/deflection circuit 20 performs luminance signal processing and deflection of the output of the signal switching circuit 19 and displays it on the monochrome cathode ray tube 21 . Image selector 22 will be described in conjunction with FIG.

Next, the character signal receiving circuit 13 will be explained with reference to FIG. In FIG. 3, 23 is a waveform shaping circuit that shapes the output of the video detection circuit 3 into a binary signal, 24 is a synchronization separation circuit, 25 is a horizontal oscillation circuit synchronized with a horizontal synchronization signal, and 26 is synchronized with a vertical synchronization signal. This is a vertical frequency divider circuit.

27 extracts the multiplexed information signal superimposed on the 20th H (and the 283rd H; hereinafter only the 20th H will be explained and the 283rd H will be omitted) based on the horizontal and vertical signals. for the 20th H
This is a gate pulse generation circuit that generates an extraction gate pulse during the second period. Gate circuit 2 for signal extraction
8, each information signal STX, PC, LN,
V, etc. are extracted and supplied to the input gate circuit 29, etc.

On the other hand, the program code signal extraction circuit 30 extracts the program code signal PC using the clock signal from the reception clock generation circuit 31 and holds it for one field period. And program code comparison circuit 32
, the program designation signal from the program designation circuit 33 and the extracted program code signal PC are compared, and when the two match, a match output is generated, and the input gate circuit 29 is opened to output the image signal V for one line. It is written into the buffer memory 34 and stored.

On the other hand, the line number code signal extraction circuit 35 uses the clock signal from the reception clock generation circuit 31 to extract the line number code signal LN. Then, in the line program code comparison circuit 36, the count output indicating the line being scanned from the line counter 37 and the extracted line number code signal LN
and when they match, transfer gate 3
8 opened and stored in buffer memory 13 1
The image signal V for a line is written and stored in the storage position of the line in the main memory 39. This main memory 39 is a storage circuit which normally has a storage capacity for one page of still images, and is driven by a clock from a main clock generation circuit 40.

By repeating such receiving and storing operations, the received image signals V can be stored one after another in the main memory 39.

Thereafter, for example, during 200H from the 42nd H to the 241st H, a readout clock is supplied to the main memory 39 at a rate of 245 bits per H to read out the stored image signal V, and the processing amplifier 41 and signal switching are performed. By applying the signal to the color cathode ray tube 6 via the circuit 5 in place of the normal television reception signal, a still image can be displayed as shown in FIG.

Further, the color code signal is extracted by a color code signal extraction circuit 42 using a clock signal from the reception clock generation circuit 31, and stored in a color code memory 43, which operates in synchronization with the reading of the image signal from the main memory 39. A color signal is generated by controlling the color signal generation circuit 44, and in addition to the processing amplifier 41, each character of the still image on the color cathode ray tube 6 is displayed in a predetermined color.

Next, referring to FIG. 4, we will explain the main parts of this embodiment, namely the signal switching circuit 5 and the audio signal selector 1.
0, character signal selector 14 and signal switching circuit 1
9 will be explained. In the figure, 45 is a double-pole, double-throw push switch, 46, 47, 48 and 49 are AND gates, 50 and 51 are OR gates, 52 is an inverter, and 53 is a terminal for applying a voltage of +5V. 54A-54J is 10
55 is a NOR gate, 56 is a NAND gate, 57 is a negative logic NOR gate, 58 is an AND gate, 59 is a switch, 60
is a terminal that applies +5V voltage. 61 is a negative logic NAND gate, 62 is an inverter, 63 and 64 are AND gates, and 65 is an inverter. 66, 67, 68, 69, 70 and 71 are AND gates, 72 is a switch, and 73 is a terminal for applying a voltage of +5V.

Next, the operation of this main part will be explained. For example, if you press pushbutton I, pushbutton switch 5
4I outputs a high-level signal while maintaining the state shown in FIG. A binary coded decimal code (1001) indicating that it is the ninth push button is output, and the ninth character signal is selected by this binary coded decimal code (1001) and output from the character signal receiving circuit 13. Ru. At this time, the high level and low level outputs of the push lock switches 54I and 54J are input to the NOR gate 55, and the NOR gate 55
The output of 5 becomes low level, and the AND gate 46,
48 is cut off, and AND gates 47 and 49 are made conductive by inverter 52. the result,
The states of the outputs of the OR gates 50 and 51 are independent of the position of the push switch 45, and the high level output of the push lock switch 54I causes the output of the OR gate 50 to go high, and the low level output of the push lock switch 54J. As a result, the output of the OR gate 51 becomes low level. Also,
When push button J is pressed, the 10th character signal is selected and output from the character signal receiving circuit 13,
The audio signal selector 10 includes OR gates 50 and 51.
The output state becomes the opposite state to that when push button I is pressed. Further, when a specific push button among the push buttons A to H is pressed, a character signal designated by that push button is selected and outputted from the character signal receiving circuit 13. At this time, the push switch 54
Since the outputs of I and 54J are both low level, the output of NOR gate 55 is high level,
As a result, AND gates 46 and 48 become conductive and AND gates 47 and 49 are cut off. Therefore, when the push switch 45 is in the state shown in FIG. 4, the output of the OR gate 50 is at a high level and the output of the OR gate 51 is at a low level.If the push switch 45 is in the state opposite to that shown in FIG. , 51 are also in opposite states.

The operation will be further explained based on the above operation. When the common terminal of the switch 72 of the image selector 22 is set to a high level as shown in FIG. , the output of the character signal receiving circuit 13 is not added to the signal processing/deflection circuit 20, but the output of the video detection circuit 18 is added,
So-called counter programs are displayed on the black and white cathode ray tube 21. In addition, since the common terminal of the switch 72 is at a high level, the AND gate 58 becomes conductive and the output of the negative logic NOR gate 57 becomes the AND gate 6.
Added to 7, 69, 71. At this time, if the common terminal of the switch 59 is at a high level, the NAND gate 56 becomes conductive and the output of the NOR gate 55 is applied directly and via the NOR gate 56. For example, if push button I or push button J is pressed, the output of the NOR gate 55 becomes low level. The low level output of this NOR gate 55 is directly applied to the first input terminal of the negative logic NOR gate 57, and after being inverted by the NAND gate 56, it is applied to the second input terminal of the negative logic NOR gate 57, and its output is As a result, the AND gates 67, 69, and 70 become conductive, and the output of the character signal receiving circuit 13 is applied to the color cathode ray tube 6. At the same time, the high-level output of the AND gate 56 turns on the AND gates 66, 68, and 70, and the output of the signal processing/deflection circuit 4 is applied to the color cathode ray tube 6 together with the output of the character signal receiving circuit 13 described above. . That is, the color cathode ray tube 6
The video and subtitles of the main program are displayed. Furthermore, if one of the push buttons A to J is pressed, for example, push button B, the output of the NOR gate 55 becomes a high level, the output of the NAND gate 56 becomes a low level, and the AND gates 66, 68, and 70 are cut off. but,
Since the output of the negative logic NOR gate 57 is at a high level, the NAND gates 67, 69, and 71 are conductive, and the output of the character signal receiving circuit 13 is transmitted to the color cathode ray tube 6.
added to. That is, only character images are displayed on the color cathode ray tube 6. Next, when the common terminal of the switch 59 is at a low level (ground), the NAND gate 56 is cut off and the NOR gate 5
Regardless of the output of 5, its output will be at a high level,
The AND gates 66, 68, and 70 are turned on, and the output of the signal processing/deflection circuit 4 is applied to the color cathode ray tube 6. Here, for example, push button I or push button J
If , the output of the NOR gate 55 becomes a low level, the output of the negative logic NOR gate 57 becomes a high level, the AND gates 67, 69, and 71 become conductive, and the output of the character signal receiving circuit 13 becomes a signal processing/signal receiving circuit.
It is applied to the color cathode ray tube 6 along with the output of the deflection circuit 4. That is, the main program video and subtitles are displayed on the color cathode ray tube 6 at the same time. Push button A
-J, for example, if push button B is pressed, the output of NOR gate 55 becomes high level, the output of negative logic NOR gate 57 becomes low level, and AND gates 67, 69, and 71 are cut off. That is, only the video of the main program is displayed on the color cathode ray tube 6.

Next, when the common terminal of the switch 72 of the image selector 22 is set to a low level (ground), the switch 5
9, the NAND gate 56 and the AND gate 58 are cut off, and their respective outputs become high and low levels, and as a result, the AND gate 6
6, 68, 70 are conductive, AND gates 67, 6
9,71 interrupts. In addition, negative logic NAND gate 6
The output of the character signal receiving circuit 13 becomes high level, the AND gate 63 is cut off, the AND gate 64 is turned on, and the output of the character signal receiving circuit 13 is applied to the signal processing/deflection circuit 20. That is, when the common terminal of the switch 72 is set to a low level, only the image of the main program is displayed on the color cathode ray tube 6, and the character image selected with the push buttons A to J is displayed on the black and white cathode ray tube 21. Ru.

As a result of this configuration, it is possible to receive text broadcasting, receive audio multiplex broadcasting, and monitor so-called alternate programs, making it easy and convenient to use.

As described above, the television receiver of this invention includes a first tuner for receiving a television signal including a multiple character signal, a multiple audio signal, and a normal video signal, and a first video intermediate frequency amplification device. a first receiving device including a circuit and a first video detection circuit; and extracting a multiple character signal that is superimposed and transmitted during a vertical retrace period of a television signal received by the first receiving device. a character signal extraction device for extracting individual character signals from the multiplexed character signal; a second receiver; a second tuner; a second video intermediate frequency amplification circuit; and a second video detection circuit. and a first display device that selectively displays a normal video signal screen output from the first receiving device and a character signal screen output from the character signal extraction device, respectively; and the character signal extraction device. a second screen for selectively displaying a screen of the character signal extracted by the device and a screen of the video signal received by the second receiving device;
a display device, and a normal video signal provided between the first receiving device and character signal extracting device and the second display device and output from the first receiving device and the character signal extracting device. a first display device for selectively supplying each of the output character signals to the first display device;
a signal switching circuit provided between the character signal extracting device and the second receiving device and the second display device, the character signal extracted by the character signal extracting device and the second receiving device a second signal switching circuit that selectively supplies the received video signal to the second display device; and a second signal switching circuit that extracts the multiplexed audio signal multiplexed into the television signal and demodulates it into individual audio signals. a voice multiplex demodulator that selects a voice signal to be demodulated by the voice multiplex demodulator; a character signal selector that selects a character signal to be extracted by the character signal extractor; By supplying a signal to the signal switching circuit, the first display device displays a screen of a normal video signal included in the television signal, and the second display device displays a screen of a character signal included in the television signal. a first display mode to
The screen of the normal video signal and the screen of the character signal are selectively displayed on the first display device, and the channel is selected on the second display device completely independently of the display contents of the first display device. a switch for switching between a second display mode for displaying a normal television broadcast screen; and a switch for generating a code signal corresponding to the program of the character signal selected by the character signal selection means; a character signal specifying means for supplying the character signal extracting device as a character signal specifying signal to be extracted; and for selecting either the main audio signal or the sub audio signal in response to the selection of the character signal by the character signal selecting means. generates a signal and supplies it to the voice selection means to output the output signal of the voice multiplexing and demodulating device so that either the main voice signal or the sub voice signal is output in accordance with the selected character signal. Since the system is equipped with automatic audio selection means that automatically selects a character signal in conjunction with the selection of a character signal by the character signal selection means, it is possible to receive text broadcasting as well as audio multiplex broadcasting, and moreover, it is possible to receive a multiplex broadcasting selection operation. It has the advantage of being simple, easy to use, and convenient. It also has the advantage of being able to monitor so-called alternate programs.

Specifically, there are the following effects, for example.

(a) It is possible to automatically combine and switch the type of subtitles and audio that complement a television program as appropriate. In other words, when the multiplexed audio is of different types, Japanese and English, if you specify Japanese as the still image subtitle display, the audio output will be switched to English, and if you specify English as the subtitle display, the audio output will be switched to Japanese. It will have an automatic switching function.

(b) a second display device capable of displaying only characters;
It is possible to display a signal (counterprogram) selected by a second tuner different from the first tuner that is input to the display device.

(c) Since the second display device does not output the audio of the signal selected by the second tuner, it will not obscure the monitor of the first display device.

(d) Voice selection by the character extraction device takes priority over voice selection by the voice selection circuit.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the still image transmission system, Figure 2
The figure is a block diagram of one embodiment of this invention, Figures 3 and 4 are block diagrams of its main parts, and Figure 5 is the second embodiment.
FIG. 5 is an explanatory diagram of the embodiment shown in FIGS. 1...Tuner circuit, 2...Video intermediate frequency amplification circuit, 3...Video detection circuit, 4...Signal processing/deflection circuit, 5...Signal switching circuit, 6...Cathode ray tube for color, 7...Audio Intermediate frequency amplification circuit, 8...Audio detection circuit, 9...Audio multiplexing demodulation circuit, 10...
Audio signal selector, 11... Speaker, 12...
Audio output terminal, 13...Character signal receiving circuit, 14
...Character signal selector, 15...Video output terminal,
16...Tuner circuit, 17...Video intermediate frequency amplification circuit, 18...Video detection circuit, 19...Signal switching circuit, 20...Signal processing/deflection circuit, 21...
Cathode ray tube for black and white, 22...image selector.

Claims (1)

[Claims for Utility Model Registration] (1) A first tuner for receiving a television signal including a multiple character signal, a multiple audio signal, and a normal video signal, and a first video intermediate frequency amplification circuit; a first receiving device including a first video detection circuit; and extracting a multiple character signal superimposed and transmitted during a vertical retrace period of a television signal received by the first receiving device; a character signal extraction device that extracts individual character signals from a multiplex character signal; a second receiving device having a second tuner, a second video intermediate frequency amplification circuit, and a second video detection circuit; a first display device that selectively displays a normal video signal screen output from the first receiving device and a character signal screen output from the character signal extraction device; and extraction by the character signal extraction device. a second display device that selectively displays a screen of the character signal received by the second receiving device and a screen of the video signal received by the second receiving device; a first display device that is provided between the display device and the first display device and selectively supplies the normal video signal output from the first receiving device and the character signal output from the character signal extraction device to the first display device. a signal switching circuit provided between the character signal extracting device and the second receiving device and the second display device, the character signal extracted by the character signal extracting device and the second receiving device a second signal switching circuit that selectively supplies the received video signal to the second display device; and a second signal switching circuit that extracts the multiplexed audio signal multiplexed into the television signal and demodulates it into individual audio signals. a voice multiplex demodulator that selects a voice signal to be demodulated by the voice multiplex demodulator; a character signal selector that selects a character signal to be extracted by the character signal extractor; By supplying a signal to the signal switching circuit, the first display device displays a screen of a normal video signal included in the television signal, and the second display device displays a screen of a character signal included in the television signal. a first display mode in which a screen of the normal video signal and a screen of the character signal are selectively displayed on the first display device, and a screen of the first display device on the second display device; a switch for switching between a second display mode that displays a normal television broadcast screen that can be selected completely independently of the displayed content; and a code signal corresponding to the program of the character signal selected by the character signal selection means. a character signal specifying means for generating a code signal and supplying the code signal to the character signal extraction device as a character signal specifying signal to be extracted; and a main audio signal or a sub audio signal in response to selection of a character signal by the character signal selecting means generates a signal for selecting one of the two, and supplies the signal to the voice selection means so that either the main voice signal or the sub voice signal is output in response to the selected character signal; A television receiver comprising automatic audio selection means for automatically selecting an output signal of the audio multiplexing and demodulation device in conjunction with the selection of character signals by the character signal selection means. (2) The television receiver according to claim 1, wherein the first display device has a color cathode ray tube and the second display device has a monochrome cathode ray tube. .