JPH0229568Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a key circuit for a video disc playback device, and in particular to a key circuit for a video disc playback device that allows the chapter search function and visual search function of the video disc playback device to be performed using the same search key. The present invention relates to a key circuit for a video disc playback device configured as follows.

[Technical background of the invention]

Conventionally, in video disc players equipped with visual search and chapter search functions, when the visual search key is pressed, the screen changes at a predetermined speed, and when the key is released, the search stops and normal playback resumes from the screen at that point. The chapter search function is such that when the chapter key is pressed, a squelch is applied to the playback signal to search for a predetermined chapter and display the image of that chapter. If you hold down the chapter key, the squelch will remain active, and when you release the key, the image of the chapter at that point will be displayed.

Furthermore, the video disc playback device is configured to be able to perform searches according to mode instructions (chapter mode, time mode, frame mode). That is, during the vertical blanking period (V BLK) of the video signal recorded on the video disk, the first
As shown in the figure, the address signal AD is, for example, the 17th,
It is inserted between 1H of the 18th and 20th horizontal periods (hereinafter referred to as 17H, 18H, and 20H). However, BS is a burst signal. A chapter code indicating the chapter is inserted in the 17th H, a time code indicating the minutes and seconds is inserted in the 18th H, and a frame code indicating the frame is inserted in the 20th H. Select a mode, extract the code signal for that mode, select the minute, second, or chapter, and display the image.

A conventional video disc playback device is constructed as shown in FIG. Reference numeral 1 denotes a video disk, which is placed on a turntable 2 and driven by a motor 3.
rotated by. A stylus 4 is provided on the surface of the video disk 1, and as the motor 3 rotates, the stylus 4 traces the recording track of the video disk 1 and picks up the video signal. This pickup signal is detected by a signal detection circuit 5 and inputted to a video signal processing circuit 6. The video signal processing circuit 6 performs FM detection, frequency conversion, etc., and demodulates the detected signal into a reproduced video signal so that it can be monitored. As mentioned above, the vertical blanking period (V
BLK) includes chapter code, time code,
Three types of mode identification signals of frame codes are inserted. A code detection circuit 7 is connected to the video signal processing circuit 6. Keyboard 8 has a chapter search forward key (CPFK), a chapter search reverse key (CPRK), a visual search forward key (VSFK),
Visual search reverse key (VSRK)
In addition to , there is a mode specification key (MIK), a numeric keypad from 0 to 9 for selecting time and chapter, etc.
There are variable speed keys for selecting normal playback, double speed, etc., and these key specifications are input to the key input processing circuit 9 and sent to predetermined designation signals CPF,
It generates CPR, VSF, VSR, and other designation signals such as mode designation signal MI ₁ and outputs them to the system control circuit 10. A mode switching instruction from the keyboard 8 is input to the system control circuit 10 through the key input processing circuit 9, and a mode switching signal MI ₂ is transferred to the code detection circuit 7. The code detection circuit 7 receives a code signal CD according to the mode switching signal MI ₂ .
(chapter code, time code, frame code) are extracted from the reproduced video signal and output to the system control circuit 10.

In the conventional video disc playback device configured as described above, when the chapter search key CPFK (or CPRK) is turned on in the chapter mode, the chapter that was specified before being turned on is accessed. At this time, use the visual search key
It does not work even if VSFK (or VSRK) is turned on.
In time mode or frame mode, a visual search is performed by turning on the visual search key VSFK (or VSRK). At this time, turning on the chapter search key CPFK (or CPRK) does not work. In this way, the chapter search key and visual search key operate according to the mode.

[Problems with background technology]

As mentioned above, in conventional video disc players, the search keys that are operated differ depending on the mode, and even if the search keys are operated, they may or may not work, and there are many search keys that need to be operated. The problem was that it was difficult to do.

[Purpose of invention]

In view of the above-mentioned points, an object of the present invention is to provide a key circuit for a video disc playback device that can reduce the number of keys and improve operability by integrating the chapter key and the visual key. It is something.

[Summary of the idea]

The key circuit of the video disc playback device of the present invention doubles as a chapter search key and a visual search key, and also uses a code detection circuit to detect the mode identification signal (code signal) contained in the playback video signal detected from the video disc. The code signal is input to a chapter code determination circuit to determine the presence or absence of a chapter code, and when a chapter code is detected, a chapter search signal is output, and a signal other than the chapter code is detected. The system is configured to automatically output a visual search signal and perform a visual search.

[Example of idea]

Embodiments of the present invention will be described below based on the drawings.

FIG. 3 is a block diagram showing the key circuit of the video disk reproducing apparatus according to the present invention, and FIG. 4 is a block diagram showing the configuration of the chapter code determination circuit of FIG. 3. In these circuits, the same parts as in FIG. 2 will be described with the same reference numerals.

The circuit shown in Figure 3 is the same as the circuit shown in Figure 2 by reducing the number of search keys on the keyboard 8 to create a forward search key (SFK) and a reverse search key (SRK). search designation signals SF, which are output from the key input processing circuit 9A corresponding to these keys.
SR and the code signal CD from the code detection circuit 7 are input to a chapter code determination circuit 11, and when the content of the code signal CD is a chapter code, the chapter code determination circuit 11 performs a chapter search. Generates signals CPF and CPR,
It is configured to generate visual search signals VBF and VBR when the code is not a chapter code.

Next, the configuration and operation will be explained in detail with reference to FIG. A video disc 1 is placed on a turntable 2 and rotated by a motor 3. A stylus 4 is provided on the top surface of the video disk 1, and as the disk rotates, the stylus 4 traces the recording track of the video disk 1 and picks up the video signal. This pickup signal is detected by a signal detection circuit 5 and inputted to a video signal processing circuit 6. The video signal processing circuit 6 performs FM detection, frequency conversion, etc., and demodulates the detected signal into a reproduced video signal so that it can be monitored.
By the way, the vertical blanking period (V
BLK) has chapter, time, and frame mode codes inserted. A chapter is inserted in the 17th H of the vertical retrace period, a time is inserted in 18H, and a frame code is inserted in 20H. A code detection circuit 7 is connected to the video signal processing circuit 6 for extracting a code signal from the reproduced video signal. Keyboard 8A is equipped with a forward key (SFK) and a reverse key (SRK) as search keys.
In addition, mode specification keys (MIK), "0 to 9"
These key instructions are input to the key input processing circuit 9A to generate a forward search designation signal (SF) and a reverse search designation signal (SR), as well as mode designation. Generates other specified signals such as signal MI ₁ . The keyboard 8A and the key input processing circuit 9A constitute key input means. A chapter code determination circuit 11 is provided between the code detection circuit 7 and key input processing circuit 9A, and the system control circuit 10. The chapter code determination circuit 11 is configured to receive a code signal CD from the code detection circuit 7 and search designation signals SF and SR from the key input processing circuit 9A. A mode switching instruction from the keyboard 8A is input to the system control circuit 10 through the key input processing circuit 9A, and a mode switching signal _MI2 is transferred to the code detection circuit 7.
The code detection circuit 7 extracts code signals (chapter, time, and frame codes) corresponding to the mode switching signal MI ₂ from the reproduced video signal, and transfers them to the chapter code determination circuit 11 and the system control circuit 10. The chapter code determination circuit 11 is a circuit that determines whether or not the code signal from the code detection circuit 7 is a chapter code.
Search designation signal SF from key input processing circuit 9A,
When the SR is in the chapter mode, it is converted into a signal for chapter search, and when it is not in the chapter mode, it is converted into a signal for visual search and transferred to the system control circuit 10.

The chapter code determination circuit 11 is constructed as shown in FIG. In response to the mode switching signal MI ₂ from the system control circuit 10, the code detection circuit 7 extracts code signals (chapter, time, and frame codes) from the reproduced video signal and sends them to the chapter code determination circuit 11 and the system control circuit 10. Forward. The chapter code determination circuit 11 includes a chapter code determination section 12 for determining the presence or absence of a chapter code, and a control signal for generating a control signal to switch the search signal generation section 14 according to the determination result of the chapter code determination section 12. Based on the search designation signals SF and SR from the switching control unit 13 and the key input processing circuit 9A, when there is a chapter code, chapter search signals CPF and CPR are generated, and when there is no chapter code (other than the chapter code), chapter search signals CPF and CPR are generated. ) is comprised of a search signal generating section 14 for generating visual search signals VBF and VBR. Note that when the code determination unit 12 detects a chapter code, it outputs a signal m indicating the presence, and when it detects a chapter code other than the chapter code, it outputs a signal n indicating the absence.
Output. When the signal m is output, the switching control section 13 operates the chapter search signal generation section of the search signal generation section 14 to enable generation of the chapter search signals CPF and CPR, and when the signal n is output, the switching control section 13 The control section 13 is the search signal generation section 1
By operating the visual search signal generation section 4, it is possible to generate visual search signals VBF and VBR. Of course, the chapter search signal CPF or visual search signal VBF is generated based on the forward search designation signal SF, and the chapter search signal CPR or visual search signal VBR is generated based on the reverse search designation signal SR. sent to.

With this configuration, two keys can be used for four purposes: visual search (forward, return) and chapter search (forward, return).
Operability can be greatly improved.

In the above embodiment, the code signal CD is used to determine whether or not the mode is chapter mode, but it is also possible to use the mode switching signal _MI2 .

[Effect of idea]

As described above, according to the present invention, it is determined whether the mode identification signal (chapter, time, frame code signals) detected in response to the mode specification is a chapter code signal, and the chapter A chapter code determination circuit is provided that outputs a chapter search signal when the signal is a code signal, and outputs a visual search signal when the signal is not a chapter code signal, so it can be used both as a chapter search key and a visual search key. No matter what mode (chapter, time, frame mode) is set, the operation corresponding to that mode will be automatically performed in response to the search key input, greatly improving operability. This gives rise to the advantage of improved performance.

[Brief explanation of the drawing]

FIG. 1 is a waveform diagram for explaining an address signal inserted into the vertical blanking period of a video signal recorded on a video disc, and FIG. 2 is a block diagram showing a key circuit of a conventional video disc playback device.
FIG. 3 is a block diagram showing a key circuit of the video disc reproducing apparatus according to the present invention, and FIG. 4 is a block diagram showing in detail the circuit configuration of the chapter code determination circuit shown in FIG. 3. 1...Video disk, 4...Stylus, 5
... Signal detection circuit, 6 ... Video signal processing circuit, 7
...Code detection circuit, 8A ...Keyboard, 9A
...Key input processing circuit, 10...System control circuit, 11...Chapter code determination circuit, SFK...Forward search key, SRK...
...Reverse search key, MIK...Mode specification key, CD...Mode identification signal (code signal),
SF...Search specification signal for forward, SR...Search specification signal for reverse, MI ₁ ...Mode specification signal, MI ₂ ...Mode switching signal, CPF...Chapter search signal for forward, CPR...Chatter for reverse VBF...Visual search signal for forward, VBR...Visual search signal for reverse.

Claims (1)

[Claims for Utility Model Registration] (1) A plurality of mode identification signals including a chapter mode are detected from a video signal recorded on a video disc according to the mode specification, and a chapter search operation is performed corresponding to each mode. , a video disc playback device capable of performing a visual search operation, comprising key input means having a mode designation key and a search key and outputting a mode designation signal and a search designation signal; means for detecting a mode identification signal corresponding to the designation from a video signal; inputting the detected mode identification signal and the search designation signal, determining whether or not the mode identification signal is a chapter code; A chapter code determination circuit is provided which generates a chapter search signal when the result is a chapter code and generates a visual search signal when the result is not a chapter code, and the mode is changed by inputting the search key. A key circuit for a video disc playback device, characterized in that a search operation corresponding to a specification is automatically performed. (2) The chapter code determination circuit includes a chapter code determination section for determining the presence or absence of a chapter code, a switching control section that generates a switching control signal according to the determination result, and a switching control section that outputs a switching control signal from the switching control section. and a search designation signal from the key input means, and when the chapter code determining section determines that there is a chapter code, it generates a chapter search signal and determines that there is no chapter code. 2. A key circuit for a video disc reproducing apparatus according to claim 1, further comprising a search signal generating section for generating a visual search signal.