JP3551003B2 - On-screen display position correction device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an on-screen display position correction apparatus for preventing an on-screen display, which is displayed by superimposing on a picture of a picture tube such as a CRT monitor of a TV or the like, from protruding or being deviated to the center due to zooming due to deflection expansion. About.
[0002]
[Prior art]
As a conventional on-screen display device, for example, Japanese Patent Application Laid-Open No. Hei 8-23502 has been proposed, which describes an example of a device for improving visibility of on-screen characters and the like during video zooming.
[0003]
The configuration and operation of the above-mentioned JP-A-8-23502 will be described with reference to FIG. In FIG. 6, white light from a light source 601 is reflected by a reflector 602, collected by a condenser lens 603, incident on a liquid crystal panel 604, and projected on a screen 606 by a projection lens 605. A zoom detection unit 607 detects the zoom position of the projection lens, and a comparison unit 609 compares the data with the data from the storage unit 608 to output a zoom position (ratio) signal. Based on this signal, the character generation unit 611 is controlled via the character control unit 610 to change the display size of the generated on-screen characters and the like. The signal from the character generation unit is superimposed on the video signal by the on-screen display control unit 612, and drives the liquid crystal panel via the display drive unit 613.
[0004]
[Problems to be solved by the invention]
However, according to the invention, when the image size of the screen is reduced or enlarged, the on-screen display or the like is not reduced or enlarged at the same ratio, and the display size of the on-screen character or the like is changed to thereby improve the visibility of the on-screen character or the like. However, the present invention does not correct the position at which on-screen characters and the like are displayed unlike the present invention. Another object of the present invention is to prevent on-screen characters or the like from protruding from the screen or being shifted toward the center when the image size is enlarged. Further, the above-described invention has a problem that it cannot be realized unless the display size of on-screen characters or the like is variable in the character generation unit.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, an on-screen display position correcting apparatus according to the present invention includes an on-screen display generation circuit for generating RGB signals for performing on-screen display, and superimposing a video signal and an output of the on-screen display generation circuit. and RGB control circuit for outputting the picture tube Te, wherein comprising a deflection circuit for deflecting the output of the RGB control circuit, and a microcomputer for controlling the on-screen display generation circuit and said deflection circuit, said microcomputer said deflection At the same time as instructing the circuit to enlarge or reduce the display image, the on-screen display generation circuit is instructed to shift the display position so that the bottom or top of the on-screen display is aligned with the bottom or top of the screen. It is obtained by the zooming by the deflection expansion of the video signal by the deflection circuit If performed, the on-screen characters and the like superimposed on the video signal in the RGB control circuit are also zoomed by deflection enlargement, and when the image is enlarged, the display screen protrudes, and when the image is reduced, the display screen is biased toward the center of the screen. At this time, the microcomputer controls the on-screen generation circuit to correct the display position of the on-screen characters, etc. This makes it possible to prevent the image from being biased toward the center.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
According to a first aspect of the present invention, there is provided an on-screen display generation circuit for generating an RGB signal for performing on-screen display, and an RGB for superimposing a video signal and an output of the on-screen display generation circuit and outputting the output to a picture tube. A control circuit, a deflection circuit for deflecting the output of the RGB control circuit, and a microcomputer for controlling the on-screen display generation circuit and the deflection circuit, wherein the microcomputer enlarges a display image to the deflection circuit or At the same time as giving an instruction to reduce the size, by giving an instruction to the on-screen display generation circuit to shift the display position so that the bottom or top of the on-screen display is aligned with the bottom or top of the screen, the on-screen display during video zooming is performed. Characters etc. are also enlarged or reduced at the same time, protruding from the screen or biased to the center Benefit that is eliminated. As described above, when performing the zooming by the deflection expansion of the video signal by the deflection circuit, the display position of the on-screen characters and the like is corrected or displayed again, so that the on-screen characters and the like are simultaneously enlarged or reduced at the time of the video zooming. This has the effect of preventing the screen from protruding or shifting to the center.
[0007]
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 5.
(Embodiment 1)
FIG. 1 is a block diagram showing an on-screen display position correcting apparatus according to an embodiment of the present invention.
[0008]
In FIG. 1, reference numeral 101 denotes an RGB control circuit, reference numeral 102 denotes an on-screen display generation circuit, reference numeral 103 denotes a microcomputer, reference numeral 104 denotes a deflection circuit, and reference numeral 105 denotes a picture tube.
[0009]
The operation of the on-screen display position correction device configured as described above will be described below.
[0010]
In FIG. 1, an on-screen generation circuit 102 generates a character or a figure to be superimposed on an image on a picture tube 105 in response to an instruction from a microcomputer 103, and outputs it to an RGB control circuit 101 as an RGB signal and an FB signal. I do.
[0011]
Also, the RGB control circuit 101 mixes the received RGB signal and video signal with the FB signal as a switch.
[0012]
The mixed video signal is adjusted in response to an instruction from the microcomputer 103 and sent to the picture tube 105 as an RGB signal.
[0013]
Further, the deflection circuit 104 generates H and V signals from the synchronization signal according to the instruction of the microcomputer 103, outputs the signals to the picture tube 105, and determines the degree of zoom of the display image.
[0014]
When the image is enlarged or reduced by the deflection enlargement, the microcomputer 103 instructs the deflection circuit 104 to increase or decrease the vertical amplitude of the image display.
[0015]
Since the video signal on which the on-screen characters and the like are superimposed is deflected and enlarged / reduced, the on-screen characters and the like on the screen are also enlarged / reduced at the same ratio. On-screen characters and the like protrude off the screen and become invisible or centered.
[0016]
In order to avoid the phenomenon in which the on-screen characters and the like protrude from the screen and become invisible, and the phenomenon in which the on-screen characters are biased toward the center, the display position of the on-screen characters and the like may be changed and redisplayed at a regular position in the screen.
[0017]
Therefore, the microcomputer 103 simultaneously shifts the display position to the on-screen generation circuit 102 so that the lowermost or uppermost portion of the on-screen characters or the like is aligned with the lower or upper edge of the screen when issuing a zooming instruction to the deflection circuit 104. On-screen characters that are off the top of the screen or near the bottom of the on-screen display are temporarily erased, and an instruction is given to re-display them at the correct position on the entire screen. Correct the display position of characters and the like.
[0018]
(Embodiment 2)
FIG. 2 is a block diagram showing an on-screen display position correcting apparatus according to an embodiment of the present invention.
[0019]
2, reference numeral 201 denotes an RGB control circuit, reference numeral 202 denotes an on-screen display generation circuit, reference numeral 203 denotes a microcomputer, reference numeral 204 denotes a deflection circuit, and reference numeral 205 denotes a picture tube.
[0020]
The operation of the on-screen display position correction device configured as described above will be described below.
[0021]
In FIG. 2, an on-screen generation circuit 202 generates a character or a figure to be superimposed on an image on a picture tube 205 in response to an instruction from the microcomputer 203 and outputs it to the RGB control circuit 201 as an RGB signal and an FB signal. I do.
[0022]
Further, the RGB control circuit 201 mixes the received RGB signal and video signal using the FB signal as a switch.
[0023]
The mixed video signal is adjusted in response to an instruction from the microcomputer 203 and sent to the picture tube 205 as an RGB signal.
[0024]
In addition, the deflection circuit 204 generates H and V signals from the synchronization signal according to an instruction from the microcomputer 203, and outputs the signals to the picture tube 205 to determine the degree of zoom of the displayed image.
[0025]
When the image is enlarged by the deflection enlargement, the microcomputer 203 instructs the deflection circuit 104 to increase the vertical amplitude of the image display.
[0026]
Since the video signal on which the on-screen characters and the like are superimposed is deflected and expanded, the on-screen characters and the like on the screen are also enlarged at the same ratio. Goes off the screen and disappears.
[0027]
In order to avoid the phenomenon that the on-screen characters and the like protrude from the screen and become invisible, the display position of the on-screen characters and the like may be changed and redisplayed at a position that fits within the screen.
[0028]
Therefore, the microcomputer 203 simultaneously shifts the display position to the on-screen generation circuit 202 so that the lowermost or uppermost portion of the on-screen characters or the like is aligned with the lower or upper edge of the screen when issuing a zooming instruction to the deflection circuit 204. On-screen characters that are off the top of the screen or near the bottom of the on-screen display are temporarily erased, and an instruction is given to re-display them at the correct position on the entire screen. Correct the display position of characters and the like.
[0029]
(Embodiment 3)
FIG. 3 is a block diagram showing an on-screen display position correcting apparatus according to an embodiment of the present invention.
[0030]
3, reference numeral 301 denotes an RGB control circuit, reference numeral 302 denotes an on-screen display generation circuit, reference numeral 303 denotes a microcomputer, reference numeral 304 denotes a deflection circuit, and reference numeral 305 denotes a picture tube.
[0031]
The operation of the on-screen display position correction device configured as described above will be described below.
[0032]
In FIG. 3, an on-screen generation circuit 302 generates a character or a figure to be superimposed on an image on a picture tube 305 in response to an instruction from a microcomputer 303, and outputs it to an RGB control circuit 301 as an RGB signal and an FB signal. I do.
[0033]
Further, the RGB control circuit 301 mixes the received RGB signal and video signal with the FB signal as a switch.
[0034]
The mixed video signal is adjusted in response to an instruction from the microcomputer 303 and sent to the picture tube 305 as an RGB signal.
[0035]
The deflection circuit 304 generates H and V signals from the synchronization signal according to the instruction of the microcomputer 303, and outputs the signals to the picture tube 305 to determine the degree of zoom of the displayed image.
[0036]
When the image is reduced by the deflection enlargement, the microcomputer 303 instructs the deflection circuit 304 to reduce the vertical amplitude of the image display.
[0037]
Since the video signal on which the on-screen characters and the like are superimposed is deflected and reduced, the on-screen characters and the like on the screen are also reduced at the same ratio. Is biased toward the center of the screen.
[0038]
In order to avoid the phenomenon that the on-screen characters and the like are biased toward the center of the screen, the display position of the on-screen characters and the like may be changed and redisplayed at a regular position in the screen. Therefore, the microcomputer 303 simultaneously shifts the display position of the on-screen generation circuit 302 so that the lowermost or uppermost portion of the on-screen characters or the like is aligned with the lower or upper edge of the screen when issuing a zooming instruction to the deflection circuit 304. On-screen characters that are off the top of the screen or near the bottom of the on-screen display are temporarily erased, and an instruction is given to re-display them at the correct position on the entire screen. Correct the display position of characters and the like.
[0039]
(Embodiment 4)
FIG. 4 is a block diagram showing an on-screen display position correcting apparatus according to an embodiment of the present invention.
[0040]
4, reference numeral 401 denotes an RGB control circuit, reference numeral 402 denotes an on-screen display generation circuit, reference numeral 403 denotes a microcomputer, and reference numeral 404 denotes a picture tube.
[0041]
The operation of the on-screen display position correction device configured as described above will be described below.
[0042]
In FIG. 4, an on-screen generation circuit 402 generates a character or a figure to be superimposed on an image on a picture tube 404 in response to an instruction from a microcomputer 403, and outputs it to an RGB control circuit 401 as an RGB signal and an FB signal. I do.
[0043]
Further, the RGB control circuit 401 mixes the received RGB signal and video signal with the FB signal as a switch.
[0044]
The mixed video signal is adjusted in response to an instruction from the microcomputer 403 and sent to the picture tube 404 as an RGB signal.
[0045]
Now, when the type of video signal changes from a 50HZ signal such as PAL to a 60HZ signal such as NTSC, the number of horizontal scanning lines changes from 625 lines to 525 lines. However, the on-screen characters and the like displayed at the bottom of the screen at this time protrude from the screen and become invisible.
[0046]
In order to avoid the phenomenon that the on-screen characters and the like protrude from the screen and become invisible, the display position of the on-screen characters and the like may be changed and redisplayed at a position that fits within the screen.
[0047]
Then, when the microcomputer 403 reads the change of the video signal, it causes the on-screen generation circuit 402 to temporarily erase the on-screen characters and the like near the bottom of the on-screen display that deviate from the original position, and to correct the entire screen. An instruction to redisplay the position is issued, and the display position of the on-screen character or the like is corrected.
[0048]
(Embodiment 5)
FIG. 5 is a block diagram showing an on-screen display position correcting apparatus according to an embodiment of the present invention.
[0049]
5, reference numeral 501 denotes an RGB control circuit, reference numeral 502 denotes an on-screen display generation circuit, reference numeral 503 denotes a microcomputer, and reference numeral 504 denotes a picture tube.
[0050]
The operation of the on-screen display position correction device configured as described above will be described below.
[0051]
In FIG. 5, an on-screen generating circuit 502 generates a character or a figure to be displayed on a picture on a picture tube 504 in response to an instruction from a microcomputer 503, and outputs the generated signal or signal to an RGB control circuit 501 as an RGB signal and an FB signal. I do.
[0052]
Further, the RGB control circuit 501 mixes the received RGB signal and video signal with the FB signal as a switch.
[0053]
The mixed video signal is adjusted in response to an instruction from the microcomputer 503 and sent to the picture tube 504 as an RGB signal.
[0054]
Now, when the type of video signal changes from a 60HZ signal such as NTSC to a 50HZ signal such as PAL, the number of horizontal scanning lines changes from 525 lines to 625 lines. However, the on-screen characters and the like displayed at the lower end of the screen at this time are biased toward the center of the screen.
[0055]
In order to avoid the phenomenon that the on-screen characters and the like are biased toward the center of the screen, the display position of the on-screen characters and the like may be changed and redisplayed at a regular position in the screen. Therefore, when the microcomputer 503 reads the change of the video signal, it causes the on-screen generation circuit 502 to temporarily erase the on-screen characters and the like near the bottom of the on-screen display that deviate from the original position, and to correct the normal size of the entire screen. An instruction to redisplay the position is issued, and the display position of the on-screen character or the like is corrected.
[0056]
【The invention's effect】
As described above, according to the on-screen display position correction apparatus of the present invention, when zooming is performed by deflecting and expanding a video signal by a deflection circuit, the display position of on-screen characters or the like is shifted or a part of the display is performed. By once deleting and redisplaying the display, it is possible to prevent the on-screen characters and the like from being enlarged or reduced at the same time during video zooming, thereby preventing the screen from protruding or being shifted to the center.
[Brief description of the drawings]
FIG. 1 is a block diagram of an on-screen display position correcting device according to an embodiment of the present invention. FIG. 2 is a block diagram of an on-screen display position correcting device according to an embodiment of the present invention. FIG. 4 is a block diagram of an on-screen display position correcting device according to an embodiment of the present invention. FIG. 4 is a block diagram of an on-screen display position correcting device according to an embodiment of the present invention. FIG. 6 is a block diagram of a conventional on-screen display device.
101, 201, 301, 401, 501 RGB control circuits 102, 202, 302, 402, 502 On-screen display generation circuits 103, 203, 303, 403, 503 Microcomputers 104, 204, 304 Deflection circuits 105, 205, 305, 404,504 picture tube

Claims (1)

An on-screen display generation circuit for generating RGB signals for performing on-screen display;
An RGB control circuit that superimposes a video signal and an output of the on-screen display generation circuit and outputs the resultant to a picture tube;
A deflection circuit for deflecting the output of the RGB control circuit;
Comprising a microcomputer that controls the on-screen display generation circuit and the deflection circuit,
The microcomputer instructs the deflection circuit to enlarge or reduce a display image, and at the same time, instructs the on-screen display generation circuit to adjust the display position so that the bottom or top of the on-screen display is aligned with the bottom or top of the screen. Give a shift instruction
An on-screen display position correction device, characterized in that:

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