JP2001136450A - Video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a video display device that allows a viewer to accurately recognize characters of time display or the like displayed at an edge of a screen. SOLUTION: The video display device is provided with a character extract means that extracts characters from a video signal including character information and a character shift means that moves the characters extracted by the character extract means to an inner position on the screen. When part of characters 23 of the time display moves out of the screen 21, the characters 23 are copied and moved to the inward position of the screen 21. Since the characters 25 after being moved are contained entirely in the screen 21, the characters can correctly be recognized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video display device such as a television receiver which displays characters such as time at the end of a screen.

[0002]

2. Description of the Related Art In a television receiver (hereinafter simply referred to as a television), a time may be displayed at an end of a screen. The character of the time display is transmitted from the broadcasting station together with the video signal, but is displayed as close to the edge of the screen as possible so that the character does not disturb the image.

[0003]

FIG. 7 (a)
As shown in the figure, the size of the transmission screen 20 sent from the broadcasting station is slightly larger than the actual size of the television screen 21. This is in order to avoid the occurrence of a black area in which nothing appears around the television screen 21.
However, since the screen size of the television screen 21 fluctuates due to factors such as variation between apparatuses and aging, if the transmission screen 20 and the television screen 21 have the above-described dimensional relationship, the end of the transmission screen 20 May protrude from the screen 21 without being fit on the television screen 21.

FIG. 7 (b) shows this concretely. The time display "7:
A part of the character 23 of "11" (broken line part) is the TV screen 2
1 shows a state in which it is out of view and becomes invisible. In this state, the characters 23 are partially missing from the television screen 21, so that the viewer cannot correctly recognize the time.

[0005] Here, the prior art of Japanese Patent Laid-Open No. 9-811 is disclosed.
No. 70 discloses a karaoke apparatus in which the display position of the lyrics telop on the screen can be arbitrarily set. However, the technique disclosed in this publication is a technology at the stage of inserting a lyrics telop (character information) at a set display position and synthesizing it with a background image. Since nothing is mentioned, it cannot be a solution to the problem described above.

SUMMARY OF THE INVENTION It is an object of the present invention to enable a viewer to accurately recognize a character displayed at an edge of a screen.

[0007]

In order to solve the above-mentioned problems, the present invention provides a character extracting means for extracting a character from a video signal containing character information, and a method for extracting a character extracted by the character extracting means into a screen. Character moving means for moving to a position.

In this way, even if a part of a character runs off the screen, the character moving means moves the character to an inward position on the screen, so that the entire character can be displayed on the screen. , Characters can be correctly recognized.

The character information included in the video signal is characterized by being a high-luminance, short-time signal. Therefore, characters are easily extracted by sequentially scanning the characters and detecting a change in luminance. be able to.

In order to move the character, the character may be moved based on the information on the extracted character and the vertical and / or horizontal movement position. In this case, the vertical movement position can be determined by the scanning position, and the horizontal movement position can be determined by the time from the start of scanning to the rise of the character.

Further, in the present invention, by providing a switch for moving characters, the viewer can arbitrarily move characters.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. FIG. 1 is a block diagram showing an example of a video display circuit according to the present invention. In the figure, 1
Is an antenna for receiving a radio wave from a broadcasting station, 2 is a tuner for extracting a signal of a predetermined channel from the received radio wave, 3 is an intermediate frequency amplifier circuit for amplifying an intermediate frequency signal from the tuner 2, 4 is an intermediate frequency amplifier A video signal processing circuit for extracting a video signal from the output of the circuit 3 and processing the video signal;
Is a deflection circuit including a synchronous circuit, a horizontal deflection circuit and a vertical deflection circuit, 6 is a CRT for displaying an image on a screen in accordance with an output from the deflection circuit 5, and 7 is a video signal processing circuit 4 which outputs an audio signal separated from a video signal. Amplifying audio amplifier, 8
Is a speaker that outputs sound. The above configuration is the same as that of a known television.

Reference numeral 9 denotes a character extracting circuit for extracting characters from the video signal of the video signal processing circuit 4, which constitutes one embodiment of the character extracting means of the present invention. Reference numeral 10 denotes a memory constituting a storage unit, which stores information on the character extracted by the character extraction circuit 9 and information on the moving position of the character. 11
Is a microcomputer constituting a control unit, and 12 is a switch operated when moving characters. In the present embodiment, the microcomputer 11, the video signal processing circuit 4, and the memory 10 constitute a character moving unit.

Next, a description will be given of a process in a case where the characters 23 are protruding from the screen 21 of the CRT 6 as shown in FIG. FIG. 2 is a flowchart showing the operation in this case. When a signal is input from the antenna 1 via the tuner 2 and the intermediate frequency amplifier circuit 3 (step S1), the video signal processing circuit 4 performs video signal processing such as video detection, video amplification, and color reproduction (step S2). ). Next, it is determined whether or not to perform character extraction (step S3). This is determined based on whether the switch 12 has been operated. If the switch 12 is not operated, it is determined that character extraction is not performed (step S3NO), and the video is displayed on the CRT 6 as it is (step S8).

When the switch 12 is operated, it is determined that character extraction is to be performed (step S3 YES), and only the character portion is extracted from the video signal by the character extraction circuit 9 (step S4). In this example, a character 23 with a time display of “7:11” is extracted, and a specific extraction method will be described later. Next, after the information on the extracted character is stored in the memory 10 (step S5), the movement position of the character is calculated (step S6). This moving position is set closer to the inside of the screen. Then, the character is pasted on the background image at that position (step S7). Details of steps S5 to S7 will also be described later. Then, the image on which the characters are pasted is output to the CRT 6 and displayed (step S8).

As a result, as shown in FIG. 3, a new display area 24 is formed on the screen 21 of the CRT 6 by shifting the display area 22 of the character 23 inward.
In addition, character 2 which is the same as character 23 protruding from screen 21
5 is displayed. That is, the character 23 is copied and displayed. As described above, by moving the extracted character to the position inside the screen 21, “7: 1
The entire character 25 of "1" is displayed in the screen 21, and the character is not lost due to the protrusion from the screen. Therefore, even if the character 23 protrudes from the screen 21 at first, the viewer can correctly recognize the time by operating the switch 12 of FIG. 1 to move the character to the position inside the screen.

FIG. 4 is a diagram for explaining a specific method of extracting and moving the characters described above. First, a method for extracting characters will be described. As shown in FIG. 4A, when extracting a character 23 such as "7", the character is scanned by a scanning line to detect a change in luminance. Here, assuming that the character 23 is scanned by the scanning lines a to e for simplicity, since the character 23 is a high-luminance signal and has a short time, FIG. b)
Pulse signals such as a to e in FIG. Therefore, the character 23 can be extracted by detecting this pulse signal by the character extraction circuit 9 (step S4). A technique for extracting characters from a video is also disclosed in, for example, Japanese Patent Application Laid-Open No. 10-320557.

Here, the time from the start of scanning at each of the scanning positions a to e to the rising of the pulse signal is represented by t.
When n (n = 1 to 5) and the width of the character obtained from the pulse signal is Wn (n = 1 to 5), the character extraction circuit 9 detects these values and stores them in the memory 10. FIG. 5 is a diagram showing the contents of the memory 10 at this time, and the rise time tn and the character width Wn are stored for each of the scanning positions a to e (step S5). Note that the scanning position b
In FIG. 4, two rise times and two character widths exist because two high-luminance portions are extracted at the scanning position b as shown in FIG. 4B.

Next, the character 23 extracted as described above
The method for moving the is described. When the character is moved, if the information on the extracted character and the vertical and / or horizontal movement position are determined, the character can be copied to that position. Here, the extracted character information is as shown in each data of FIG. 5 described above, and the vertical movement position is determined by the scanning position. Here, as shown in FIG. Move to v to z. On the other hand, the horizontal movement position is determined by the time until the rising of the character, and here, as shown in FIG. 4C, from the original character 23 (for convenience, shown at scanning positions v to z). The character 25 rises at a timing delayed by the time t0. Since the rise time of the original character 23 is tn, the rise time T from the start of scanning of the moved character 25 is T = tn + t0. Note that the character width of the character 25 at each of the scanning positions v to z is the character 23
Has the same value as the character width Wn.

The microcomputer 11 performs the above-described calculation of T for each of the scanning positions v to z, and stores the result in the memory 10 (step S6). FIG. 6 is a diagram showing the contents of the memory 10 at this time.
The rise time T and the character width Wn are stored corresponding to .about.z. These data are read out from the memory 10 and supplied to the video signal processing circuit 4, and the video signal processing circuit 4 creates a video signal in which the character 25 after the movement is pasted on the background video according to the above data (the above-described data). Step S7), this is output to CRT6. As a result, FIG.
As shown by, the character 25 of the time display moved to the position inside the screen 21 is displayed.

In FIG. 3, both the character 23 before the movement and the character 25 after the movement are displayed. However, the character 23 before the movement is erased by electrical processing, and only the character 25 after the movement is displayed. May be. Also, in the above description, the characters are manually moved by the switch 12, so that the viewer can move the characters arbitrarily. It is also possible to move the character to. Further, when the character is moved by the switch 12, the amount of movement of the character may be made variable in accordance with the amount of operation of the switch so that the character can be moved to an arbitrary position.

In the above embodiment, the character is moved in both the vertical and horizontal directions. However, the character may be moved in only one of the directions depending on the state of the character protruding.
In FIG. 4C, the horizontal movement amounts are tn and t0.
And the value of T changes according to these, but the horizontal position of the moving character may be fixed with T being a constant value.

In the above embodiment, the time display is given as an example of the character. However, in the present invention, the character is not limited to the time display, and may be, for example, a caption displayed in a breaking news report. Further, in the above-described embodiment, the case where the video signal to which the character information is added is received from the broadcasting station has been described. However, the present invention receives the video signal from the VTR and moves the character of the channel display added to the reproduced video. It is also possible to apply to such a case.

[0024]

According to the present invention, even when a part of a character runs off the screen, the entire character is displayed on the screen by moving the character to an inward position on the screen. Can be correctly recognized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a video display circuit according to the present invention.

FIG. 2 is a flowchart illustrating an operation of the video display circuit.

FIG. 3 is an enlarged view of a character display portion on a screen.

FIG. 4 is a diagram illustrating a method of extracting and moving a character.

FIG. 5 is a diagram showing the contents of a memory;

FIG. 6 is a diagram showing the contents of a memory.

FIG. 7 is a diagram for explaining character protrusion on a conventional screen.

[Explanation of symbols]

 Reference Signs List 1 antenna 2 tuner 3 intermediate frequency amplification circuit 4 video signal processing circuit 5 deflection circuit 6 CRT 7 audio amplifier 8 speaker 9 character extraction circuit 10 memory 11 microcomputer 12 switch 24 character display area 25 characters

Claims (5)

[Claims] 1. A video display device which receives a video signal containing character information and displays characters at an end of a screen, a character extracting means for extracting characters from the video signal, and a character extracting means for extracting characters from the video signal. A character moving means for moving the characters to an inward position on the screen. 2. The video display device according to claim 1, wherein the character extracting means extracts the character from a change in luminance due to the scanning of the character. 3. A character moving means for moving a character based on information on the character extracted by the character extracting means and a vertical and / or horizontal moving position.
Or the video display device according to 2. 4. The image display apparatus according to claim 3, wherein the vertical movement position is determined by the scanning position, and the horizontal movement position is determined by a time from the start of scanning to the rise of the character. 5. The video display device according to claim 1, further comprising a switch for moving a character.