JPH01252094A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To easily execute respective types of monitors by outputting a video signal only when a video signal concerning a waveform is outputted and outputting the video signal only when the video signal concerning the waveform is not outputted. CONSTITUTION:Respective signals of an envelope 12 of an input video signal 10, an output video signal 11 and a regenerative FM signal are inputted to a waveform generating circuit 13. The circuit 13 selects one signal out of three signals by the command of a control signal 15 from a switching control circuit 14, generates a waveform signal to display the waveform to a picture monitor and generates a scale signal which becomes a level reference. A switch 16 switches a part of a video signal section excluding the synchronizing signal section of an output video signal to a waveform signal generated by the circuit 13 and outputs it from a video monitor output terminal 17, by the command from the circuit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Field of Industrial Application) This invention relates to a recording/reproducing device having a monitoring function.

(Prior art) Recording and playback devices that record and playback video signals, especially recording and playback devices used for business purposes, check whether the equipment is operating normally when recording or playing back. A system having a monitor device as shown in FIG. 4 is used for the purpose of adjusting the level of the video signal.

In FIG. 4, reference numeral 32 is a recording/playback device that records and plays back video signals in this way, and this recording/playback device 32 is connected to a video display monitor (hereinafter abbreviated as picture monitor) via a connection cable. 33 and a waveform monitor 34 are connected. Here, picture monitor 3
3 is for checking the video recorded on the recording/playback device 32, and the waveform monitor 34 is for checking the operational waveform inside this recording/playback device 32.

Incidentally, although such a system can perform accurate recording and reproduction because the waveform monitor 34 is used, it has the disadvantage that the overall system configuration becomes complicated. For example, when used outdoors, such systems are often inconvenient because they are required to be smaller, lighter, and consume less power.

(Problems to be Solved by the Invention) Although the conventional recording/reproducing system including the monitor device can perform accurate recording and reproducing, it has the disadvantage that the system configuration is complicated.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a recording/reproducing apparatus that has various monitoring functions and can simplify the system configuration.

[Structure of the Invention] (Means for Solving the Problems) The present invention is an apparatus for recording and reproducing a video signal, which generates a signal related to the waveform of a signal related to the video signal and converts it into a video signal. When a video signal related to a waveform is being output, only the video signal is output, and when a video signal related to a waveform is not being output, only the original video signal is output.

(Function) In this invention, when a video signal related to a waveform is output, only the video signal is output, and when a video signal related to a waveform is not output, only the video signal is output, so that Various types of monitoring can be performed simply by connecting a video display monitor. Therefore, the system configuration is simplified.

(Embodiment) Next, an embodiment in which the present invention is applied to a magnetic recording/reproducing system will be described.

FIG. 1 is a diagram showing the configuration of a recording/reproducing apparatus according to this embodiment.

In the figure, reference numeral 1 denotes a magnetic tape, and the signal recorded on this magnetic tape 1 is an FM-modulated video signal.

Reference numeral 2 denotes a video input terminal into which a video signal to be recorded is input, and the video signal input to the video input terminal 2 is converted into a digital signal by an A/D converter in the input signal/signal processing circuit 3. After being subjected to band compression and delay necessary for recording, it is D/A converted and sent to the recording circuit 4 as an analog signal.

The recording circuit 4 performs FM modulation on the video signal, amplifies the current, and supplies a recording current to the recording head 5. As a result, a video signal is recorded from the recording head 5 onto the magnetic tape 1.

On the other hand, when reproducing a signal from the magnetic tape 1, the signal read by the reproducing head 6 is amplified by the reproducing circuit 7, subjected to necessary waveform equalization, FM demodulated, and sent to the output signal processing circuit 8.

The output signal processing circuit 8 converts the signal input from the reproduction circuit 7 into a digital signal by A/D converting it, performs processing such as removing time axis fluctuations and restoring the signal band, performs D/A conversion, and outputs a video. Output from terminal 9.

Now, in the system of this embodiment, by connecting a picture monitor (not shown) to the video monitor output terminal 17 of the recording/playback device shown in FIG. Three types of waveforms can be observed: a human video signal waveform, an output video signal waveform, and an envelope waveform of a reproduced FM signal.

Therefore, in addition to the configuration of the conventional recording/reproducing apparatus described above, the following configuration is provided.

That is, reference numeral 13 denotes a waveform generation circuit 13 to which the human video signal 10, the output video signal 11, and the envelope 12 of the reproduced FM signal are input, and this waveform generation circuit 13 receives one of the three signals. Switch control circuit 1
4, and generates a waveform signal for displaying the waveform on the picture monitor, as well as a scale signal serving as a level basis.

In response to a command from the switching control circuit 14, the switch 16 switches a part of the video signal section of the output video signal excluding the synchronization signal section to the waveform signal generated by the waveform generation circuit 13.
It is output from the video monitor output terminal 17.

Note that the signals 18 from the output signal processing circuit 8 to the waveform generation circuit 13 and the switching control circuit 14 are a synchronization signal and a clock signal that serve as operating standards for each circuit.

Further, a signal 20 from the operation circuit 19 to the switching control circuit 14
is a selection signal determined by an operator's operation.

FIG. 2 is a block diagram showing a detailed configuration of the waveform generation circuit 13 shown in FIG. 1. Note that the same elements as those shown in FIG. 1 are given the same numbers. In FIG. 2, reference numeral 21 denotes the input video signal 10. This is a changeover switch that selects either one of the output video signal 11 and the envelope 12 of the reproduced FM signal, and the signal selected by this changeover switch 21 is converted into a digital signal by an A/D converter 22.

The read/write memory 23 temporarily stores the digital signal from the A/D converter 22 according to the write address 25 given from the control circuit 24, and reads it according to the read address 26 different from the write address, so that the digital signal selected by the changeover switch 21 can be read out according to the read address 26 different from the write address. The voltage waveform of a signal over a certain period of time is converted into a scanning line signal for display on a picture monitor.

The read-only memory 27 is a read-only memory for generating a scale signal that serves as a level reference on the television screen, and similarly to the read-write memory 23, the read-only memory 27 is a read-only memory that generates a scale signal that serves as a level reference on the television screen. , generate a scale signal.

The signals read from the read/write memory 23 and the read-on memory 27 are combined by the OR circuit 28, the DC level and gain are adjusted by the level setting circuit 29, and the signals are sent to the switch 16 shown in FIG.

Therefore, in the picture monitor connected to the video monitor output terminal 17 of this recording/playback device, as shown in FIG.
Input video signal waveform, output video signal waveform and playback F
A waveform 31 such as an envelope waveform of the M signal is displayed.

This eliminates the need for a conventional waveform monitor. In addition, a scale is displayed along with the waveform, allowing accurate measurements.

In the embodiment described above, in order to display a waveform, a part of the video signal section of the output video signal excluding the synchronization signal section is switched to a waveform signal generated by the waveform generation circuit 13, and the waveform signal is output from the video monitor output terminal 17. However, the entire video signal section of the output video signal except for the synchronization signal section may be used. In this case, the waveform will be displayed on the entire surface of the picture monitor.

In addition, the present invention may of course use waveforms other than the three types mentioned above as the waveform display. For example, the waveform may be a demosulator out signal, a control track signal, or the like.

Furthermore, if the present invention is applied to a high-definition television system, accurate monitoring will be possible as the image quality improves.

Further, in the embodiment described above, a configuration for directly inputting the signal from the input signal processing circuit 3 to the output signal processing circuit 8 can be added as necessary. In this case, a switching circuit for switching between the signal from the reproduction circuit 7 and the signal from the input signal processing circuit 3 is required before the output signal processing circuit 8.

[Effects of the Invention] As described above, the recording/reproducing apparatus of the present invention has various monitoring functions and can simplify the system configuration.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a recording/reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a detailed block diagram of a waveform generation circuit in this embodiment, and FIG. 3 is a diagram showing a monitor in this embodiment. FIG. 4 is a diagram illustrating a conventional technique. 1...Magnetic tape, 2...Video input terminal, 3...
- Human signal processing circuit, 4... Recording circuit, 5... Recording head, 6... Playback head, 7... Playback circuit, 8.
...Output signal processing circuit, 9...Video output terminal, 13
...Waveform generation circuit, 14...Switching control circuit, 16.
··switch.

Claims (1)

[Claims] (1) A recording/playback device that records and plays back a video signal, comprising: a signal generation unit that generates a signal related to the waveform of the signal related to the video signal; and a signal conversion unit that converts the signal generated by the signal generation unit into a video signal. means, a signal output means for outputting these video signals, and when a video signal related to a waveform is output from the signal conversion means, outputs only the video signal from the signal output means, and converts the video signal into a waveform from the signal conversion means. A recording/reproducing apparatus characterized by comprising: a control means for controlling to output only a video signal from the signal output means when the video signal is not being outputted.