JPH08116500A - Superposing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved superimposing device for blanking only a part for displaying graphic information among video signals. SOLUTION: This device is provided with an on-screen data signal source 10 for generating on-screen data signals for indicating the graphic information, a blanking signal generator 20 for combining the red, green and blue components of the on-screen data signals and generating blanking signals, a video amplifier 40 for eliminating the video signals while the blanking signals are at a high level and generating partially eliminated video signals and a mixer 50 for superimposing the on-screen data signals to the partially eliminated video signals from the video amplifier 40 and generating superimposed video signals further.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superimposing device for superimposing an on-screen data signal representing graphic information on a video signal representing video information. In particular, it relates to a super-imposing device that can generate a blanking signal using an on-screen data signal.

[0002]

2. Description of the Related Art Generally, in a video apparatus such as a television or a video cassette recorder, a so-called on-screen display (on-screen display) is used.
A super-imposing device is used to perform the spray: OSD). The super-imposing device superimposes graphic information representing a channel, a volume, and / or a time on a video signal and displays it on a screen at a specific position.

A typical superimposing device is
An on-screen data signal representing graphic information,
An on-screen data signal source for generating a blanking signal for blanking a video signal representing an image is used. When the video signal is supplied in video line units, each video line is cut off, that is, blanked while the blanking signal is at a high level, and an on-screen data signal is provided in the blanked part of the video line. By being inserted, a video on which graphic information is superimposed is generated.

However, conventional super-imposing devices are designed to bring the blanking signal to a high level during a predetermined portion of each video line on which graphic information is to be superimposed. As a result, on the screen where the graphic information is superimposed and displayed, the graphic information is displayed in, for example, a rectangular area where the video signal is blanked. Since the blanked rectangular area contains only graphic information but no video information, the video is hidden behind the blanked area and cannot be seen.

Furthermore, since the on-screen data signal and the blanking signal are generally output from the on-screen data signal source through different output terminals, the overall structure of the super-imposing device is complicated.

[0006]

SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide an improved super-imposing device capable of generating a blanking signal so as to blank only a portion of a video signal where graphic information is inserted. To provide.

[0007]

To achieve the above object, according to the present invention, there is provided a superimposing device for a video device for superimposing an on-screen data signal representing graphic information on the video signal. A signal source for generating the on-screen data signal, blanking signal generation means for generating a blanking signal synchronized with the on-screen data signal from the on-screen data signal, and the blanking signal according to the blanking signal. Erasing means for removing the video signal to produce a partially erased video signal while the ranking signal is at a high level; and the on-screen data signal for partially erasing the video signal from the erasing means. Superimposed on
There is provided a superimposing device having a superimposing means for generating a superimposed video signal.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to the drawings based on preferred embodiments.

FIG. 1 shows a circuit diagram of a super-imposing device for superimposing graphic information on a video signal according to the present invention. The video signals used in the present invention are signals of red, green and blue components (VR, VG and V) demodulated from a composite color video signal.
B) is included.

The super-imposing device of the present invention is
It includes an on-screen data signal source 10, a blanking signal generator 20, a video amplifier 40, and a mixer 50.

When the on-screen display mode is initiated by pressing one of the function buttons of a video device such as a television or a video cassette recorder, the on-screen data signal source 10 indicates the channel, volume and / or time of day. Generating an on-screen data signal at a DC voltage level that represents graphic information (eg, numbers, symbols or characters). The on-screen data signal source 10 (eg, a microcomputer) is programmed so that the on-screen data signal is displayed at a specific position on the screen. The on-screen data signal includes red, green and blue components O that can be selectively generated by the on-screen signal source 10.
It has SDR, OSDG and OSDB. Therefore, the OS
When any one of DR, OSDG and OSDB is selected, the graphic information is displayed in a color corresponding to the selected color component. OSDR, OSDG and OSDB
The respective signals are supplied to the blanking signal generator 20 and the mixer 50.

The blanking signal generator 20 has an OSD.
A blanking signal BL is generated according to R, OSDG and OSDB. This blanking signal generator 20 is
It is composed of a combination unit 30 and a switching unit 35. The combination unit 30 includes a pair of transistors 22, 24, 26.
Have. Each of the transistors 22, 24, 26 has a base for receiving OSDR, OSDG, OSDB, and
It has an emitter connected to the ground and a collector commonly connected to one contact 28 and connected to the drive voltage Vcc via a resistor. Each transistor 22, 24, 26 is O
It is turned on according to each of SDR, OSDG and OSDB to generate a switching control signal which is an inversion of the on-screen data signal. This switching control signal is supplied to the switching unit 35 through the contact 28.

The switching section 35 has a switching transistor 32 which functions to invert the input switching control signal. The switching transistor 32 has a base for receiving the switching control signal and an emitter connected to the ground. , And a collector connected to the drive voltage Vcc via a resistor. The inverted signal from the switching unit 35 has a level of Vcc and is supplied to the video amplifier 40 as a blanking signal BL having the same waveform as the on-screen data signal.

As will be appreciated by those skilled in the art, transistors 22, 24, 2 in blanking signal generator 20.
The combination of 6 and 28 is OSDR, OSDG and O.
It is equivalent to an OR gate that performs an OR operation on the SDB signal. Therefore, when any one of OSDR, OSDG and OSDB is supplied to the blanking signal generator 20, the blanking signal generator 20 generates a blanking signal synchronized with the on-screen data signal.

The basic function of the video amplifier 40 is to amplify the red, green and blue components VR, VG and VB of the video signal. However, when the high level blanking signal BL is received from the blanking signal generator 20, the red, green and blue components VR, VG and VB are partially erased while the blanking signal is at the high level. Therefore, when each color component VR, VG, VB of the video signal is supplied to the video amplifier 40 in video line units, each video line corresponds to the position occupied by the graphic information in the image while the blanking signal is at the high level. It is cut off at the part that does.

The mixer 50 includes OSDR, OSDG and OSDB and VR, VG and VB from the video amplifier 40.
And are superposed, and a corresponding set of superposed video signals SR, SG and SB are output.

The operation of the superimposing device shown in FIG. 1 will be described below with reference to FIGS. 2A, B, C, D and E. In FIG. 2, only one component of the on-screen data signal and the video signal is shown as an example.

Normally, when no on-screen data signal is generated from the screen data signal source 10, an image of only video information is displayed on the screen.

However, when in the on-screen display mode, the on-screen data signal source 10 is switched to the one shown in FIG.
The high level on-screen data signals OSDR, OSDG and OSDB12 as shown in FIG. Then, those signals are supplied to the combining unit 30 in the blanking signal generator 20. The blanking signal generator 20 includes OSDR, OSDG and OSD.
The logical sum operation of B is performed to generate the high-level blanking signal BL as shown in FIG. 2B. The blanking signal BL is synchronized with the on-screen data signal. Then, this blanking signal is supplied to the video amplifier 40.

In the video amplifier 40, the VR, VG and VB signals as shown in FIG. 2C are blanking signals B.
While L is at the high level, it is erased and the waveform as shown in FIG. 2D is output. As described above, the video signal from the video amplifier 40 having the erasing portion 14 is supplied to the mixer 50. The mixer 50 superimposes the OSDR, OSDG, and OSDB signals from the on-screen data signal source 10 on the erased portion 14 of VR, VG, and VB,
The superimposed video signal S as shown in FIG. 2E.
Generates R, SG and SB.

While particular embodiments of the invention have been described above, it will be appreciated by those skilled in the art that various modifications can be made without departing from the scope of the claims set forth herein. .

[0022]

Therefore, according to the present invention, unlike the prior art, since the blanking signal is generated by using the on-screen data signal to be superimposed on the video signal, the blanking signal including the graphic pattern to be displayed is generated. Only the graphic pattern can be displayed on the screen without creating a ranked "area" and the video information between the graphic elements displayed on the screen can be viewed. Further, the output terminal for outputting the blanking signal, which has been conventionally required for the on-screen data signal source, is unnecessary.

[Brief description of drawings]

FIG. 1 is a schematic circuit diagram of an improved super-imposing device according to the present invention.

2A, 2B, 2C, 2D, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, 2E, and 2A represents the signal waveform generated from the on-screen data signal source 10, FIG. 2B represents the signal waveform generated from the blanking signal generator 20, and FIG. 2C is erased by the BL signal in the video amplifier 40. 2D represents the output signal waveform from the video amplifier 40 and FIG. 2E represents the output waveform from the mixer 50.

[Explanation of symbols]

 10 on-screen data signal source 12 on-screen data signal 14 erase part of video signal 20 blanking signal generator 22, 24, 26, transistor 28 contact 30 combination part 32 transistor 35 switching part 40 video amplifier 50 mixer BL blanking signal Vcc Drive voltage

Claims (3)

[Claims] 1. A super-imposing device for a video device for superimposing an on-screen data signal representing graphic information on a video signal, comprising: a signal source for generating the on-screen data signal; Blanking signal generating means for generating a synchronized blanking signal from the on-screen data signal, and removing the video signal and partially erasing the blanking signal according to the blanking signal while the blanking signal is at a high level. And a superimposing means for superimposing the on-screen data signal on the partially erased video signal from the erasing means to generate a superposed video signal. Is a super-imposing device. 2. The on-screen data signal has red, green and blue components, and the video signal is red.
The super-imposing device according to claim 1, having a green component signal and a blue component signal. 3. The supermarket according to claim 2, wherein the blanking signal generating means has means for generating the blanking signal by combining red, green and blue components of the on-screen data signal. Importing device.