JPH0622321A - Teletext broadcast receiver - Google Patents

Abstract

PURPOSE:To convert display colors whose brightness difference is small into display colors having a large brightness difference when the display colors whose brightness difference is small are in existence side by side in a teletext pattern. CONSTITUTION:R, G, B teletext information data outputted from a display circuit 9 are respectively stored in R, G, B VRAMs 21a-21c. Then a conversion section 23 is used to replace teletext information data from each of the VRAMs 21a-21c to R, G, B terminals of a CRT 10 in response to a replacement command of each display color of a teletext pattern given by the operation of a pallet switch 22d of an operation section 22. Thus, when the display colors whose brightness difference is small are in existence side by side in a teletext pattern, the display colors are converted into display colors having a large brightness difference resulting in offering easy to see combinations of colors.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a teletext receiver for receiving teletext.

[0002]

2. Description of the Related Art A conventional teletext receiving apparatus is constructed as shown in FIG.

That is, as shown in FIG. 6, the television signal of the channel selected by the tuning means 1 is received by the tuner 3 via the antenna 2, and the video intermediate frequency signal is amplified by the video intermediate frequency amplifier circuit 4. After being amplified, the video detection circuit 5 demodulates the video intermediate frequency signal to extract the video signal, and the audio signal separated by the video intermediate frequency amplification circuit 4 is demodulated by the audio detection circuit 6.

When the display switching means 7 is switched to the television screen side, the output of the video detection circuit 5 is input to the signal processing circuit 8 via the display switching means 7 and the signal processing circuit 8 outputs a synchronizing signal. The separated and extracted video signal and the separated synchronizing signal are input to the display circuit 9, and the display circuit 9 scans the electron beam of the television picture tube (hereinafter referred to as CRT) 10 which is an image display means on the basis of these signals. An image is displayed on the screen of the CRT 10, and the audio signal demodulated by the audio detection circuit 6 is input to the speaker 11 via the display switching means 7, and the reproduced sound is output from the speaker 11.

By the way, as is well known, character broadcasting is performed by using some scanning lines among a plurality of scanning lines in a vertical blanking period which is a time gap of a video signal. A teletext signal is multiplexed in the form of a digital signal, and the broadcasting station repeatedly sends a program consisting of several pages at a time interval of about 20 seconds per page, replacing the information as soon as the latest information comes in, and the receiving side The target program can now be accessed at the same time intervals, and each TV broadcasting station is currently providing multiple teletext program services. Such teletext is received and played as follows. To be done.

That is, when a predetermined teletext program is selected and operated by the teletext program selecting means 12, the program information of the selected teletext program is stored in the program information memory 13.
When the teletext program stored in the program information memory 13 is broadcast, the teletext program selection means 12 controls the channel selection means 1 to receive the radio wave of the teletext program, and the video detection is performed in the same manner as the above-described operation. The circuit 5 demodulates the multiplexed video signal of the teletext signal, and the demodulated video signal is input to the text decoder 14 via the display switching means 7 switched to the teletext screen side.

By the way, the character decoder 14 is controlled by the character broadcast program selecting means 12 so as to operate at the time of broadcasting the character broadcast program, and the character broadcast signal multiplexed with the video signal inputted through the display switching means 7. Is decoded, the decoded character information data is input to the display circuit 9 via the display switching means 7, the CRT 10 displays the character information, and the decoded character information data is stored in the program memory 15 as necessary. It

At this time, if voice information is included in the information decoded by the character decoder 14, reproduced voice is output through the display switching means 7 and the speaker 11.

[0009]

By the way, in the ordinary teletext, eight colors of black, blue, green, cyan, red, magenta, yellow, and white are displayed by a combination of three primary colors of red, green, and blue.
The brightness value of each of these colors is expressed as an integer value in which black is "0" and white is "10", and "0", "1", "6", "7",
"3", "4", "9", "10", and when the display color portions having a small difference in luminance value are adjacent to each other on the text broadcast screen, for example, when white characters are displayed on the yellow background color portion, , Yellow and white luminance values are "9" and "1" respectively
Since it is 0 ", white display characters may not be clearly recognized, and especially when the teletext receiving device is mounted on a moving body such as an automobile, it is difficult to see the screen due to vibration during traveling, There is a problem that it becomes more difficult to recognize white display characters.

Therefore, the present invention has been made in order to solve the above problems, and when display color portions having a small difference in luminance value are adjacent to each other on the teletext screen, these display colors are changed to the luminance value. The purpose is to be able to convert to a display color with a large difference.

[0011]

A teletext receiver according to the present invention comprises a tuner, a channel selection means, a video intermediate frequency amplification circuit, a video detection circuit, an audio detection circuit, and a signal for separating a video signal and a sync signal. A television receiving circuit including a processing circuit and a display circuit for controlling the image display means, a selected teletext program is stored in a program information memory, and the teletext program stored in the program information memory is broadcast at the time of broadcasting. The teletext program selection means for controlling the channel selection means to receive a program, and the output of the video detection circuit and the input of the signal processing circuit are respectively connected and disconnected by the switching operation of the television screen or the text information screen. Display switching circuit,
A character decoder, which is controlled by the character broadcast program selecting means during broadcasting of the selected character broadcast program, decodes a character broadcast signal detected by the video detection circuit and input through the display switching circuit, and a decoded character decoder. In a teletext receiver provided with a program memory for storing character information data, red, green, and blue are stored between the display circuit and the image display means, respectively. Storage means is provided, and an operation part for changing the display color of each part of the teletext screen by the image display means is provided, and in accordance with the operation of the operation part, the red color of the image display means from the storage means, It is characterized by the provision of a converter that exchanges character information data input to the green and blue terminals.

[0012]

In the present invention, the red, green, and blue character information data output from the display circuit are stored in the respective red, green, and blue storage means, and the characters given by the operation of the operating section are stored. In response to an instruction to switch the display colors of the respective parts of the broadcast screen, the conversion unit causes the storage unit to display red, green,
Since the character information data for the blue terminal is exchanged, when the display color part with a small difference in the brightness value of the teletext screen is adjacent, operate the operation part so that the display color is the one that is the easiest to see. Is converted into a display color having a large difference in luminance value.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a part of an embodiment of a teletext receiving apparatus of the present invention, FIGS.
Is a flowchart for explaining the operation.

1 is different from FIG. 6 in that R and G for storing respective character information data for red (R), green (G) and blue (B) between the display circuit 9 and the CRT 10. , A video RAM as storage means for B (hereinafter referred to as VRAM)
21a, 21b, 21c are provided, and an operation section 22 having keys for changing the display color of each section of the teletext screen by the CRT 10 is provided, and the VRAMs 21a to 21c are connected to the R of the CRT 10 according to the operation of the operation section 22. , G,
A conversion unit 23 for exchanging the character information data to the B terminal is provided, and the conversion unit 23 is composed of a conversion control unit 24 and a pallet 25 from the CPU, and the pallet 25 is used for each VRAM.
21a to 21c and the CRT 10 are installed.

By the way, as shown in FIG. 2, the operation unit 22 has three program selection first, second and third switches 22.
a, 22b, 22c and one pallet switch 22d are provided, and the program memory 15 is provided via the character decoder 14.
When the program number of the data stored in (see FIG. 6) is input to the conversion control unit 24, the first to third switches 22a-2
2c, the program number table 26 (see FIG. 2) provided in the conversion control section 24 is associated with the program number and each of the operated switches 22a to 22c. When the switch 22a is turned on,
The table 26 stores the program number XX corresponding to the switch number "1" of the first switch 22a, and so on.

On the other hand, when the pallet switch 22d is operated in order to convert the character broadcasting programs of the numbers ◯◯, ΔΔ, and □□ into the most visible display colors, the pallet switch 22d is operated once. The pallet number by a hexadecimal counter that counts the number of operations changes from 0 to 5, and the R, G, B character information data to the CRT 10 is exchanged by the pallet 25 according to this pallet number as shown in FIG. It is possible to switch the display colors in a total of 6 ways. For example, the palette switch 22
If d is not operated, the pallet number is "0" and R, G, B
The pallet number is set to "1" when the pallet switch 22d is operated once, and the original R and B character information data are exchanged and input to the CRT 10, and the pallet switch 22d is not exchanged.
When is operated four times, the pallet number becomes "4", and the original character information data for R and G is exchanged and input to the CRT 10. In this way, each character broadcast is displayed in a color that the user feels most readable. By operating the pallet switch 22d for each program and appropriately selecting a combination of display colors, the pallet table 27 provided in the conversion control unit 24 as shown in FIG.
22c corresponding to switch numbers "1" to "3", "0" to "5" based on the number of times the pallet switch 22d is operated.
The palette numbers up to are stored.

In FIG. 3, R, G and B represent R, G and B character information data, and 0 to 5 represent palette numbers.

When the teletext program is actually reproduced and displayed, the switch corresponding to the operated switch is operated based on the data stored in the program number table 26 by the operation of any of the first to third switches 22a to 22c. The character information data of the program is read from the program memory 15 by the character decoder 14 and input to the display circuit 9 as R, G, B character information data, and R, G, B based on the data stored in the palette table 27. The pallet 25 operates to replace the respective character information data of, and the desired character broadcast program is displayed on the CRT 10 in the display color that is the easiest to see.

Next, a series of operations will be described with reference to the flowchart of FIG.

First, as shown in FIG. 4, it is judged whether or not the power is on (step S1).
When the determination result is YES, the predetermined initialization process is performed (step S2) to determine whether or not there is a program display request, that is, the first to third switches 22a for program selection. It is determined whether or not any of .about.22c has been operated (step S3), and this determination is repeated until YES is passed.

Then, the first to third switches 22a to 22
If any of the operations of c is performed and the determination result of step S3 is YES, it is determined whether or not the character information data of the selected program is stored in the program memory 15 (step S4). If the determination result is NO, the desired teletext program has not yet been received, so the normal teletext program reception processing is performed (step S5), and the text information data of the received teletext program is stored in the program memory. 1
5, and the conversion control unit 24 stores the program number of the teletext program at the position of the switch number in the corresponding program number table 26.
If the switch 22a is operated, the switch number of the program table 26 is stored in the position of "1", and as a result, step S4 is passed with YES and the process proceeds to the next step S5.

Next, the conversion control section 24 refers to the palette table 27 (step S6). If data is stored in the palette table 27 at this time, the display color is converted based on the data stored in the palette table 27. After that (step S7), it is judged whether or not there is a program switching operation, that is, a switch operation other than the switch judged to have been operated in step S3 (step S7).
8) If the determination result is YES, the palette number is stored in the position of the switch number of the palette table 27 corresponding to the program selected immediately before the switching (step S).
9) Then, the process returns to the determination of step S8.

On the other hand, if the decision result in the step S8 is NO, it is decided whether or not the power is off (step S1).
0) If the determination result is NO, it is determined whether or not the pallet switch 22d is operated (step S11). If the determination result is NO, the process returns to step S8, and if the determination result is YES, Pallet switch 22
After the display color is converted according to the number of operations of d (step S12), the process returns to step S8.

If the result of the determination in step S10 is YES, the pallet number is stored in the switch number position of the pallet table 27 corresponding to the program selected immediately before the power is turned off (step S13). Operation ends.

Therefore, when the display color portions having a small difference in the luminance value of the teletext screen are adjacent to each other, the operating portion is operated so that the display color becomes the most visible display color. The difference can be increased to make it easier to see, and the teletext screen can be clearly recognized even when the teletext receiving device is installed in an automobile.

Next, another embodiment of the present invention will be described with reference to FIG.

FIG. 5 shows a part of a block diagram. In FIG. 5, the difference from FIG. 1 is that the pallet 25 in FIG. 1 is deleted and a work memory 28 is newly provided, together with the conversion control unit 24. The conversion unit 29 is configured, and the conversion control unit 24
Thus, of the data stored in the VRAMs 21a to 21c for R, G, and B, one of the data stored in the two VRAMs to be replaced based on the above-mentioned pallet number is temporarily transferred to the work memory 28 and then stored in the work memory 28. The other VRA that should be replaced with the VRAM that transferred the data
After the data stored in M is transferred, the data stored in the work memory 28 is transferred to the other VRAM, and the display colors of the teletext screen are switched in this manner.

Therefore, by using the work memory 28, the same effect as in the case of FIG. 1 can be obtained.

In each of the above-described embodiments, three program selection switches are provided and the display colors are exchanged for three teletext programs. However, the number of program selection switches to be provided is three. Of course, the number is not limited to one, two, or even four or more may be provided.

Needless to say, the teletext receiver of the present invention is not limited to being mounted on a moving body, but can be applied to a stationary type.

[0031]

As described above, according to the teletext receiving apparatus of the present invention, an image from the storage means is converted from the storage means by the conversion section in response to the instruction to change the display color of each section of the teletext screen given by the operation of the operation section. Since the character information data for the red, green, and blue terminals of the display means are exchanged, the operation section is operated so that the display color with the smallest difference in brightness value of the teletext screen is adjacent to the display color that is most visible. By doing so, these adjacent portions can be converted into display colors with a large difference in luminance value, and even when the teletext receiving device is mounted on a mobile body such as an automobile, the teletext screen is displayed in the most legible state. Can be displayed.

[Brief description of drawings]

FIG. 1 is a block diagram of a part of an embodiment of a teletext receiving device of the present invention.

FIG. 2 is an operation explanatory diagram of FIG.

FIG. 3 is an operation explanatory diagram of FIG. 1.

FIG. 4 is a flowchart for explaining the operation of FIG.

FIG. 5 is a block diagram of a part of another embodiment of the present invention.

FIG. 6 is a block diagram of a conventional teletext receiver.

[Explanation of symbols]

1 channel selection means 2 tuner 4 video intermediate frequency circuit 5 video detection circuit 6 audio detection circuit 7 display switching means 8 signal processing circuit 9 display circuit 10 CRT (image display means) 12 character broadcast program selection means 13 program information memory 14 character decoder 15 program memory 21a, 21b, 21c R, G, B VRAM (storage means) 22 operation unit 23, 29 conversion unit

Claims (1)

[Claims] 1. A tuner, a channel selection means, a video intermediate frequency amplification circuit, a video detection circuit, an audio detection circuit, a signal processing circuit for separating a video signal and a sync signal, and a display circuit for controlling an image display means. A television receiving circuit and a teletext for storing the selected teletext program in a program information memory and controlling the tuning means so as to receive the teletext program when the teletext program stored in the program information memory is broadcast. Program selection means, a display switching circuit that connects and disconnects the output of the video detection circuit and the input of the signal processing circuit by a switching operation of a television screen or a text information screen, and broadcasting of the selected teletext program. At the same time, it is controlled by the teletext program selecting means, is decoded by the video detection circuit, and decodes the teletext signal inputted through the display switching circuit. In a teletext receiver including a character decoder and a program memory for storing decoded character information data, each character information data for red, green, and blue is respectively provided between the display circuit and the image display means. Storage means for storing red, green, and blue is provided, and an operation section for changing the display color of each part of the teletext screen by the image display means is provided, and from each of the storage means according to the operation of the operation section. A teletext receiver, comprising a conversion unit for exchanging text information data input to the red, green, and blue terminals of the image display means.