KR960012887B1 - Cdg player - Google Patents

Abstract

The device automatically converts the mode into the super-impose mode or into the CDG internal mode by the input of an outer video signal in the CDG player. The device comprises: a synchronous signal separator(10) for extracting and separating the outer horizontal and vertical synchronous signal from the outer video signal produced by the outer video image source; a CDG decoder(20); a phase comparator(30) for comparing the phase of the outer vertical and horizontal synchronous signal; a phase compensating value controlling device(40) for generating phase compensating signal; an oscillator(50) for oscillating the time of a clock signal; a RGB encoder(60) for encoding the RGB color signal of graphic information from the CDG decoder(20); and a switching device(70) for switching the outer image signal and the graphic signal into an image based on the superimposing timing signal.

Description

CDG Player

1 is a block diagram of a CDG player having a general superimpose function.

FIG. 2 is a block diagram of a playback device having a superimpose function, which is an improvement of the CDG playback device shown in FIG.

3 (a) to 3 (d) show an example of the result of superimposing an external video signal and a durable graphic signal based on the superimposed timing signal from the CDG decoder shown in FIG. drawing.

4 is a block diagram of a CDG player according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

10: synchronization separator 20: CDG decoder

30: phase comparison unit 40: phase compensation value control unit

50: oscillator 60: RGB encoder

70: switching unit 80: burst gate pulse generator

90: synchronization signal control means 100: synchronization signal switching means

The present invention relates to a CDG reproducing apparatus, and more particularly, to a CDG reproducing apparatus capable of automatically switching to a superimpose mode requiring an external video signal or to a CDG internal mode requiring no external video signal according to the presence or absence of an external video signal. It is about.

Now, with the development of 'video disc' which is a composite medium of video and audio, it has been able to create a new type of software called visual music, and it is a complete system that works as a single system by combining audio and video. With the birth of / V equipment, it became a full-fledged A / V era where video and audio coexist.

As the A / V era begins in earnest, the public's attention to pure audio culture, which presupposes only auditory appreciation, is gradually shifting toward the A / V culture where audio-visual coexists. As a forerunner, a multi-disc player (MDP) that reads information from a disc-shaped information storage medium and reproduces a video signal and an audio signal has attracted attention.

The multi-disc player reads image information and / or audio information recorded on a disc-shaped information storage medium such as a compact disc graphic (CDG) or a laser disc (LD) to perform image signal processing and / or audio signal processing, respectively. The audio signal is output through the speaker and the video signal is played through the monitor.

The information storage medium employed in the multi-disc player as described above, for example, the compact disc graphics are not only good sound quality thanks to the voice code and 8-bit sub code signal recorded on the disc, but also a high level of random access. And graphic displays are possible.

Here, the 8-bit subcode signal recorded on the compact disc graphic is located in the channels P, Q, R, S, T, U, V, and W. The dual P and Q channels are already used for the random access and reproduction of the multi-disc player. It is used for time display and track number display, and the remaining R to W channels are used for graphic data transmission.

As such, in general, a superimpose function is widely employed to display graphic data on a compact disc graphic, for example, lyrics data or caption data, on a monitor together with a video signal provided from an external source such as a television.

The CDG reproducing apparatus having the superimpose function generally extracts and separates an external horizontal synchronous signal and an external vertical synchronous signal from an external video signal provided from an external video source such as a television as shown in FIG. A synchronization separator 10, a CDG decoder 20 for decoding the graphic information recorded in the subcode on the CDG disc, an external horizontal synchronization signal from the synchronization separator 10, and an internal from the CDG decoder 20; Controls the phase comparator 30 for comparing the phases of the horizontal sync signal, and the oscillator 50 for oscillating the source clock of the internal horizontal sync signal in order to compensate for the phase difference detected as a result of the comparison in the phase comparator 30. An RGB encoder for encoding R, G, and B color signals for graphic information applied from the CDG decoder 20 based on the composite synchronization signal from the phase compensation value control unit 40 and the CDG decoder 20. And a switching unit 70 for superimposing the external video signal and the graphic signal from the RGB encoder 60 at high speed according to the superimposition timing signal from the CDG decoder 20. do.

The CDG playback operation by the CDG playback device having the general superimpose function configured as described above is as follows.

First, the sync separator 10 extracts and separates an external horizontal sync signal and an external vertical sync signal from an external video signal provided from an external video source such as a television. Then, the CRT controller (not shown) installed in the CDG decoder 20 is reset by the external vertical synchronization signal, and the clock signal from the oscillator 50 input to the CDG decoder 20 is divided by 910. The generated internal horizontal synchronizer signal and the separated external horizontal synchronizer signal are applied to the phase comparator 30. Accordingly, the phase comparison unit 30 compares the phases of the external horizontal synchronization signal and the internal horizontal synchronization signal, and the phase compensation value control unit 40 compensates the phase difference when the phase difference is detected as a result of the comparison. For example, the phase compensation value control signal for controlling the time of the clock signal oscillated by the oscillator 50 is outputted, and the oscillator 50 according to the phase compensation control signal source clock, for example, 14, It will oscillate 31818 MHz. The CDG decoder 20 synthesizes the oscillation frequency and the internal vertical synchronization signal and is applied to the RGB encoder 60 as a composite synchronization signal. Thus, the RGB encoder 60 encodes R, G, and B color signals for graphic information outputted from the decoding result of the CDG decoder 20. Accordingly, the switching unit 70 superimposes the external video signal from the external video source and the graphic signal (internal video signal) output from the RGB encoder 60 from the output terminal A of the CDG decoder 20. Based on the imposing timing signal (Superimposing Timing) to switch at high speed to produce a single screen (image) to output.

According to the above-described configuration operation, the oscillation unit 50 oscillates the source clock of the internal horizontal synchronization signal in accordance with the phase compensation value control signal output from the phase compensation value control unit 40 so that the internal horizontal synchronization signal and the external horizontal synchronization signal coincide with each other. When an abnormality occurs in the source clock oscillated by the oscillator 50, the output state of the analog R, G, and B color signals encoded by the RGB encoder 60 becomes poor, for example, on a television monitor. An image that appears on the screen is not displayed correctly, but an unstable screen is displayed such as a shaking image or an unnatural color.

Accordingly, as shown in FIG. 2, the CDG playback apparatus having the superimpose function, which is an improvement of the CDG playback apparatus, extracts an external horizontal synchronization signal and an external vertical synchronization signal from an external video signal provided from an external video source. And a CDG decoder 20 which decodes the graphic information recorded in the subcode on the CDG disc, an external horizontal synchronization signal from the sync separator 10, and the CDG decoder 20. A phase comparator 30 for comparing the phases of the internal horizontal synchronization signals from the oscillator 50 for generating a source clock of the internal horizontal synchronization signals to compensate for the phase difference detected as a result of the comparison in the phase comparator 30; RGB for encoding R, G, and B color signals for graphic information applied from the CDG decoder 20 based on the composite synchronization signal from the CDG decoder 20 and the phase compensation value control unit 40 for A switching unit 70 for switching the external video signal and the graphic signal from the RGB encoder 60 at high speed in accordance with the superimposition timing signal from the coder 60 and the CDG decoder 20, and superimposing. The burst gate pulse generator 80 outputs an internal color subcarrier pulse based on the composite synchronization signal output from the CDG decoder 20, and the internal color subcarrier pulse applied to the RGB encoder 60 is received. Synchronizing signal control means 90 which controls the external color subcarrier pulse synchronization of the external video signal to be synchronized with the internal color subcarrier pulse.

In addition, the synchronization signal control means 90 may adjust the phase of the internal color subcarrier pulse applied by the burst gate pulse generator 80 and the phase of the external color subcarrier pulse according to the external image signal provided from the external image source. A phase compensating control unit 90B for outputting a phase compensating control signal so that the comparable phase difference can be compensated if the phase comparator 90A to be compared with the phase comparator 90A is detected as a result of the comparison; And an oscillation section 90C made of, for example, a crystal oscillator which applies the color subcarrier oscillated in accordance with the phase compensation value control signal from the phase compensation value control section 90B to the RGB encoder 60.

The CDG playback operation by the CDG playback device having the improved superimpose function configured as described above is as follows.

As an external video signal provided from an external video source such as a television is applied to the synchronization separating unit 10, it is separated into an external horizontal synchronization signal and an external vertical synchronization signal. Then, the CRT controller (not shown) installed in the CDG decoder 20 is reset by the external vertical synchronization signal, and the internal signal generated by dividing the clock signal from the oscillator 50 input to the CDG decoder 20 by 910 is generated. The horizontal synchronization signal and the separated external horizontal synchronization signal are applied to the phase comparator 30. Accordingly, the phase comparator 30 compares the phase of the external horizontal synchronizing signal with the phase of the internal horizontal synchronizing signal, and as a result, outputs from the phase compensating control unit 40 when a phase error is detected. The oscillator 50 oscillates the clock signal whose source clock oscillation time of the internal horizontal synchronizing signal is adjusted so that the internal horizontal synchronizing signal coincides with the external horizontal synchronizing signal, that is, 14.31818 MHz. Accordingly, the CDG decoder 20 divides the oscillation frequency by 910 to generate a phase-compensated internal horizontal synchronizing signal, and synthesizes the phase-compensated internal horizontal synchronizing signal and the internal vertical synchronizing signal and outputs the composite synchronizing signal. The R, G, and B color signals of the graphic information according to the decoding result are output. In addition, the CDG decoder 20 outputs the superimposition timing signal for determining the superimposition time through the output terminal A in outputting the composite synchronization signal and the R, G, and B color signals.

In this way, while the various signals are output from the CDG decoder 20, the burst gate pulse generator 80 outputs the internal color subcarrier pulses based on the composite synchronization signal output from the CDG decoder 20. The internal color subcarrier pulses are applied to the RGB encoder 60 and the synchronization signal control means 90. Accordingly, the phase comparator 90A constituting the synchronization signal control means 90 is external to the internal color subcarrier pulse phase from the burst gate pulse generator 80 and the external video signal provided by the external video source. The phase compensation value controller 90B compares the phases of the color subcarrier pulses and the phase compensation value control unit 90B compares the phase compensation values so that the synchronization of the external color subcarrier pulses is synchronized with the synchronization of the internal color subcarrier pulses when the phase difference is detected. The oscillator 90C outputs a control signal and oscillates the color portion carrier frequency 3. 579545 MHz after the phase compensation value control signal is correctly phase compensated and applied to the RGB encoder 60. After encoding the R, G, and B color signals for the graphic information output as a result of the decoding in the CDG decoder 20, the color ban after corrected phase compensation. The graphic signal is output according to the wave frequency. Accordingly, the switch SW of the switching unit 70 is, for example, the superimposing timing output from the output terminal A of the CDG decoder 20 as shown in FIG. On the basis of the signal, the graphic signal (internal video signal) shown in FIG. 3 (b) is output in the sections t1 and t2, and the external video signal shown in FIG. 3 (a) is output in sections other than the t1 and t2 sections. It is switched at a high speed as much as possible so that a video signal as shown in FIG. 3 (d) is output on one screen (video).

According to the CDG reproducing apparatus with the improved superimpose function as described above, the external color of the external video signal is synchronized to the internal color subcarrier pulse synchronously applied to the RGB encoder 60 by the control operation of the synchronization signal control means 90. As the subcarrier pulses are synchronized, an unstable image is not displayed, but a more stable image is displayed.

On the other hand, CDG discs include video accompaniment, oral fairytales, and education. CDG discs for video accompaniment display only lyrics in the background color except for the beginning and end of a song. It is necessary to superimpose lyrics or subtitles that are read and played from a CDG disc in the same external video, but CDG discs for movie play and education do not need an external video to superimpose because they are completely processed with their own graphics.

For this reason, a CDG disc player or a multi-disc player that has a superimpose function, for example, superimpose mode and external video that superimposes external video and lyrics when an external video signal is input depending on whether an external video signal is input or not. When inputting the signal ratio, it is required to switch to the CDG internal mode in which the entire graphic processing is performed only by the graphic itself.

In addition, since the external video is not required for the CD and CD for the CD and the education, the phase of the horizontal synchronization signal is not accurately compensated when the mode is switched from the superimpose mode to the CDG internal mode. This causes problems such as flickering or flickering.

Accordingly, the present invention has been made in view of the above circumstances, and an object thereof is to automatically switch to a superimpose mode that requires an external video signal or a CDG internal mode that does not require an external video signal, depending on whether an external video signal is input or not. In addition, the present invention provides a CDG reproducing apparatus in which a horizontal synchronization signal phase of a corresponding mode is accurately compensated and a stable screen is displayed.

In order to achieve the above object, a CDG reproducing apparatus according to an embodiment of the present invention includes a synchronization separator for extracting and separating an external horizontal synchronization signal and an external vertical synchronization signal from an external image signal provided from an external image source, and a CDG disc. A CDG decoder which decodes the graphic information recorded in the subcode of the image, a phase comparing unit which compares the phase of the external horizontal synchronization signal from the synchronization separating unit and the internal horizontal synchronization signal from the CDG decoder, and the phase comparing unit In the CDG playback device having a phase compensation control unit for controlling the oscillator for oscillating the source clock for the internal horizontal synchronization signal applied to the CDG decoder to compensate for the phase difference detected as a result of the comparison, by determining the presence of an external video signal input When there is an input of an external video signal, the external horizontal synchronization signal from the synchronization separator is Comparison, if there is no input of the external video signal while controlling so that the applied portion is self-standard horizontal synchronizing signals are the phase comparison part configured by having a synchronizing signal switching means added to the control to be applied.

According to a preferred embodiment of the present invention, the synchronization signal switching means includes a synchronization detector for detecting synchronization of the external video signal as the external video signal is input, and an external horizontal synchronization signal when the external video signal is not input. A clock oscillator for oscillating a reference clock, a divider for dividing the reference clock signal oscillated by the clock oscillator 910 to generate a standard horizontal synchronizing signal, which is a substitute for an external horizontal synchronizing signal, and whether or not a detection signal from the synchronization detecting unit And a switching unit for switching switching so that a horizontal synchronization signal is applied to the phase comparing unit.

According to the present invention configured as described above, according to the presence or absence of the external video signal, the horizontal synchronization signal as a comparison target applied to the phase comparison unit is changed through the switching unit in the synchronization signal switching means, and then the phase of the horizontal synchronization signal is accurately compensated. And a stable image is displayed.

Hereinafter, with reference to the accompanying drawings will be described the present invention in more detail.

4 is a block diagram of a CDG reproducing apparatus according to an embodiment of the present invention, in which the same components as those shown in FIG. 2, that is, the sync separating unit 10, the CDG decoder 20, and the phase comparing unit ( 30), the description of the phase compensation value control unit 40, the oscillator 50, the RGB encoder 60, the switching unit 70, the burst gate pulse generator 80, and the synchronization signal control means 90 will be omitted. .

Reference numeral 100 denotes an external video signal input from an external video source such as a multi-disc player or a television (not shown), and when there is an external video signal input, an external horizontal synchronous signal output from the synchronization separating unit 10. Is controlled to be applied to the phase comparator 30, but when there is no input of an external video signal, it is a synchronization signal switching means for controlling its own standard horizontal synchronizer to be applied to the phase comparator 30.

Here, the synchronization signal switching means 100 detects synchronization of the external video signal as an external video signal is input and outputs a detection signal, and an external horizontal synchronizer when the external video signal is not input. A reference clock for making a signal, that is, a clock oscillator 100B for oscillating a clock signal of 14.31818 MHz band, a reference horizontal signal oscillated in the clock oscillator 100B by 910, and a standard horizontal synchronous signal that is a substitute for an external horizontal synchronous signal. The frequency divider 100C for generating a signal and the external horizontal synchronization signal from the synchronization separator 10 are connected to the phase comparator 30 when there is a detection signal from the synchronization detector 100A. In the absence of the detection signal, the switching unit 100D is connected so that a standard horizontal synchronization signal from the divider 100C is applied to the phase comparator 30.

Referring to the CDG playback operation by the CDG playback device according to an embodiment of the present invention configured as described above are as follows.

In FIG. 4, first, when the synchronization detection unit 100A in the synchronization signal switching unit 100 detects synchronization of the external video signal, the detection signal is output accordingly so that the switch SW2 of the switching unit 100D is automatically operated. This is connected to the output terminal of the synchronization separator 10 to perform the superimpose mode operation. Thereafter, similar to the block diagram of FIG. 2, the CG controller (not shown) installed in the CDG decoder 20 is reset by the external vertical synchronization signal separated by the synchronization separator 10, and the CDG decoder 20 is reset. The internal horizontal synchronizing signal generated by dividing the clock signal from the oscillator 50 input into 910 by 910 and the external horizontal synchronizing signal separated from the synchronizing separator 10 are applied to the phase comparator 30. Accordingly, when the phase error is detected as a result of the comparison in the phase comparator 30, the source clock oscillation time of the internal horizontal synchronization signal is generated by the oscillator 50 according to the phase compensation control signal output from the phase compensating value controller 40. This adjusted clock signal is oscillated. Accordingly, the CDG decoder 20 divides the oscillation frequency by 910 to generate a phase compensated internal horizontal synchronizing signal, and synthesizes the phase compensated internal horizontal synchronizing signal and the internal vertical synchronizing signal and outputs the composite vertical signal. The R, G, and B color signals of the graphic information according to the decoding result are output. In addition, the CDG decoder 20 outputs a superimposition timing signal for determining a superimposition time through an output terminal A in outputting the composite synchronization signal and the R, G, and B color signals.

On the other hand, the burst gate pulse generator 80 outputs an internal color subcarrier pulse based on the composite synchronization signal output from the CDG decoder 20, and the internal color subcarrier pulse is synchronized with the RGB encoder 60. As applied to the signal control means 90, the phase comparator 90A constituting the synchronization signal control means 90 has an internal color subcarrier pulse phase from the burst gate pulse generator 80 and an external image source. The phases of the external color subcarrier pulses of the external image signal provided by the PSA are compared, and the phase compensation value controller 90B compares the phases of the external color subcarrier pulses with the synchronization of the internal color subcarrier pulses when the phase difference is detected. Phase compensating control signal is outputted so that the synchronization is synchronized with the oscillator 90C. 3.579545, which is the color carrier frequency after the phase compensating exactly according to the phase compensating control signal. By oscillating MHz and applying it to the RGB encoder 60, the RGB encoder 60 encodes R, G, and B color signals for graphic information output as a result of decoding from the CDG decoder 20, and then accurately compensates for the phase. And outputs a graphic signal according to the color subcarrier frequency. Accordingly, the switch SW1 of the switching unit 70 has a high speed based on the superimposition timing signal output from the output terminal A of the CDG decoder 20 so that the external image signal and the graphic signal are superimposed. The switching operation is performed so that a screen (image) is output.

On the other hand, if there is no synchronization signal of the external video signal detected by the synchronization detection unit 100A, there is no output of the detection signal accordingly, so that the switch SW2 automatically divides the divider to perform the operation of the CDG internal mode ( 100C) output terminal. Subsequently, the reference clock signal of the 14.31818 MHz band oscillated by the clock oscillator 100B is divided 910 by the divider 100C and applied to the phase comparator 30 as a standard horizontal synchronization signal. At this time, the reset pin of the CRT controller (not shown) in the CDG decoder 20 is set to the high state, that is, the internal reset mode, and the CDG decoder 20 is internally leveled. When the synchronization signal is applied to the phase comparator 30, the phase comparator 30 compares the phases of the standard horizontal synchronization signal and the internal horizontal synchronization signal. As a result of the comparison, when the phase error is detected, the phase compensation operation and the subsequent processing procedures are performed as in the superimpose mode, and there is no superimposition timing signal output from the CDG decoder 20. Therefore, only the internal video signal output from the RGB encoder 60 is output through the switching unit 70.

As described above, according to the CDG playback apparatus according to an embodiment of the present invention, the horizontal synchronization signal to be compared to the phase comparison unit through the switching unit in the synchronization signal switching means is changed according to whether the external video signal is inputted and the phase comparison is performed. Since the phase of the horizontal synchronization signal applied to the negative is accurately compensated by the compensation operation, an unstable screen such as a screen shake is not generated.

Claims (2)

A synchronization separator 10 for extracting and separating an external horizontal synchronization signal and an external vertical synchronization signal from an external image signal provided from an external image source, and a CDG decoder 20 for decoding graphic information recorded in a subcode on a CDG disc. A phase comparison unit 30 for comparing the phase of the external horizontal synchronization signal from the synchronization separating unit 10 and the internal horizontal synchronization signal from the CDG decoder 20, and the comparison in the phase comparison unit 30; In the CDG reproducing apparatus having a complementary compensation controller 40 for controlling the oscillator 50 for oscillating a source clock for the internal horizontal synchronization signal applied to the CDG decoder 20 so that the detected phase difference is compensated for, Determining whether there is an external video signal input and controlling the external horizontal synchronization signal from the sync separator 10 to be applied to the phase comparator 30 when there is an external video signal input. If there is no input of the external video signal CDG player, characterized in that the self-standard horizontal synchronizing signal synchronizing signal switching means (100) for control to be applied to the phase comparison unit 30 is configured is provided additionally. The synchronization signal switching unit (100) of claim 1, wherein the synchronization signal switching unit (100) detects synchronization of the external video signal as an external video signal is input, and an external horizontal synchronization signal when the external video signal is not input. A clock oscillator 100B for oscillating a reference clock for making a signal, a divider 100C for generating a standard horizontal synchronizing signal substituted for an external horizontal synchronizing signal by dividing the reference clock signal oscillated in the clock oscillating unit 100B by 910; And a switching unit (100D) which is switched so that the horizontal synchronization signal is applied to the phase control unit (30) in accordance with the presence or absence of a detection signal from the synchronization detection unit (100A).