JPH06168501A - Video tape recorder - Google Patents

Abstract

PURPOSE:To easily edit a video tape irrespective of any input video signal by means of detecting a VPS signal from not only a 1st video signal from a tuner but also a 2nd video signal from an external input terminal. CONSTITUTION:The 2nd video signal inputted through the external input terminal 12 is given to a switch 22 after the deterioration in frequency performance of the VPS signal is corrected by a correction circuit 16. However, the 1st video signal from the tuner 28 is given to the switch 22 as it is. Consequently, the VPS signal is detected in the 1st video signal or 2nd video signal by a VPS signal detecting circuit 24. This VPS signal is compared with a previously set VPS signal by a controller 32, and when both of them coincide, a recording control signal is inputted to a video signal processing circuit 26 from the controller 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video tape recorder, and more particularly to a video tape recorder for recording a desired program by using a VPS signal used in PAL system broadcasting.

[0002]

2. Description of the Related Art VPS signals are described in, for example, "PAL V" in Sanyo Technical Review Vol. 19 (August 1987).
As described in "TR WITH VPS", etc., 2.5M inserted in the 16th H of the vertical blanking period.
Binary data of Hz, one V for one TV program
Corresponds to PS signal. Therefore, in the video tape recorder, by presetting a specific code of this VPS signal at the time of timer reservation, only the period during which the code is transmitted is recorded, so that the broadcast time of the program is the time set by the timer. Even if they are different, you can always record the desired program.

In a conventional video tape recorder 1 utilizing such a VPS signal shown in FIG. 6, a VPS signal detecting circuit 3 is detected from a video signal inputted through a tuner 2.
The VPS signal is detected by and the controller 4 compares the detected VPS signal with the VPS signal preset in the controller 4. Then, only when the comparison results match, the video signal processing circuit 5 is operated to record the video signal from the tuner 2.

[0004]

In such a conventional video tape recorder 1, since the VPS signal of the video signal inputted through the external input terminal 6 is not detected, it is possible to edit and record from another tape. The desired program must be searched and edited each time, which causes a problem that editing is troublesome.

Further, even if the video signal input through the external input terminal 6 is input to the VPS detection circuit 3 during editing, the 2.5 MHz band containing the VPS signal is recorded last time. The VPS detection circuit 3 may not be able to detect the VPS signal because it is deteriorated due to. Therefore, a main object of the present invention is to provide a video tape recorder which can easily edit a video signal from an external input.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a code detecting means for detecting a code included in a video signal, and a first video signal from a tuner or a second video signal from an external input terminal is switched to the code detecting means. It is a video tape recorder provided with input switching means for inputting and means for controlling recording based on a code detected by a code detecting means.

[0007]

The first video signal from the tuner is unchanged, or the second video signal output from another video tape recorder and input via the external input terminal is a portion containing a code such as a VPS signal. After being corrected by the correcting means, the frequency characteristic of is given to the input switching means. Then, when the input switching means selects the second video signal, the VPS signal (code) is detected from the second video signal in which the frequency characteristic of the specific portion is corrected by the code detecting means such as the VPS signal detecting circuit. It Therefore, for example, the VPS preset in the controller
If the signal (code) and the detected VPS signal (code) match, the second video signal is recorded on the video tape.

[0008]

According to the present invention, a code such as a VPS signal is detected not only from the video signal from the tuner but also from the video signal from the external input terminal. Therefore, when the code is input via the external input terminal. But it can be edited easily. If the correction means is used, even if the VPS signal (code) of the second video signal has a deterioration in frequency characteristics,
The VPS signal (code) can be surely detected.

The above-mentioned objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of the embodiments with reference to the drawings.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a video tape recorder 10 of this embodiment includes an external input terminal 12. For this reason,
For example, a video signal output from another video tape recorder 14 is input to the video tape recorder 10 via the external input terminal 12. V of the input video signal
The PS signal passes through the switch 18 after the deterioration of the frequency characteristic is corrected by the correction circuit 16, but the video signals other than the VPS signal directly pass through the switch 18 without passing through the correction circuit 16. This is because the switch 18 is connected to the terminal 18a during which the VPS signal is recorded and connected to the terminal 18b during which the VPS signal is not recorded by the control signal from the switch control circuit 20. As shown in FIG. 2, the VPS signal is composed of binary data of 2.5 MHz inserted in the 16th H of the vertical blanking period.

Then, the video signal passing through the switch 18 is passed through the switch 22 acting as an input switching means, and the VPS signal detection circuit 24 and the video signal processing circuit 26 are supplied.
Entered in. Here, the switch 22 is connected to the terminal 22a when the video signal is input through the tuner 28, and is connected to the terminal 22b when the video signal is input through the external input terminal 12. The switch 22 is controlled by a Tu / AV switch button (not shown) of the front switch 30.

The VPS signal detection circuit 24 detects the VPS signal included in the video signal, and then the controller 3
In step 2, the controller 32 operates the front switch 30 to compare the VPS signal preset with the VPS signal detected by the VPS signal detection circuit 24. When the two match, the controller 32
A recording control signal is output from the video signal processing circuit 26, thereby operating the video signal processing circuit 26. That is, the video signal is recorded by the video signal processing circuit 26 and then recorded on a video tape (not shown). Since the recording control signal is also used for controlling other mechanisms, the terminal 34
Is output from.

As can be seen from FIG. 3, the video signal input to the switch control circuit 20 is first sync-separated by the sync separation circuit 36. That is, the horizontal synchronizing signal as shown in FIG. 4A and the vertical synchronizing signal as shown in FIG. 4E are separated and input to the mono-multis 38a and 38b and the mono-multis 38c and 38d, respectively. Therefore, the outputs of the monomultis 38a and 38b are triggered by the falling edge of the horizontal synchronizing signal as shown in FIGS. 4 (B) and 4 (C), and fall after a predetermined time elapses. Also,
The outputs of the mono-multis 38c and 38d also rise at the fall of the vertical synchronizing signal as shown in FIGS. 4 (F) and (G), and fall after a predetermined time has elapsed. Of these outputs, the outputs of the monomultis 38a and 38b are subsequently input to the EXOR circuit 40a, and the exclusive OR is taken by this to output the waveforms shown in FIGS. 4D and 4I. It Also, Mono Multi 38c and 38d
Is output to the EXOR circuit 40b and a waveform as shown in FIG. 4 (H) is output. After that, the EXOR circuit 4
The outputs of 0a and 40b are ANDed by the AND circuit 42 to output the waveform shown in FIG. Therefore, the switch 18 is connected to the terminal 18a only during the high level period of the waveform shown in FIG. 4 (J), that is, the period of the VPS signal.

4A to 4D and 4E to 4E.
The scale of the time axis is different from that of (J).
The waveform of (I) is the scale of the waveform of FIG.
It is adapted to the waveforms of (E) to (H) and (J). In operation, when the video tape recorder 14 reproduces a video tape having a plurality of programs recorded based on the VPS signal as shown in FIG. 5A, the reproduced video signal is input to the video tape recorder 10. . Then, after the frequency characteristic of the VPS signal is corrected by the correction circuit 16, the VPS signal is detected by the VPS signal detection circuit 24, and this VPS signal is input to the controller 32.
Here, for example, the controller 32 is provided with VPS signals a and V
If the PS signal e is set, the recording control signal is output from the controller 32 only when the program having the VPS signal a and the program having the VPS signal e are input to the controller 32, whereby the video signal processing circuit is produced. 26 operates. Therefore, as shown in FIG. 4 (B), the video tape shows the program having the VPS signal a and the VPS signal e.
Is recorded.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a waveform diagram showing a VPS signal.

FIG. 3 is a block diagram showing a switch control circuit of the embodiment of FIG.

FIG. 4 is a waveform diagram showing waveforms of respective parts of the block diagram shown in FIG.

FIG. 5 is an illustrative view showing a program recorded on a video tape.

FIG. 6 is a block diagram showing a conventional technique.

[Explanation of symbols]

 10 ... Video tape recorder 12 ... External input terminal 16 ... Correction circuit 24 ... VPS signal detection circuit 26 ... Video signal processing circuit 32 ... Controller

Claims (2)

[Claims] 1. Code detection means for detecting a code included in a video signal, input switching means for switching and inputting a first video signal from a tuner or a second video signal from an external input terminal to the code detection means, A video tape recorder comprising means for controlling recording based on the code detected by the code detecting means. 2. The video tape recorder according to claim 1, further comprising a correction unit that corrects a frequency characteristic of a specific portion of the second video signal between the external input terminal and the input switching unit.