JPH05153625A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To simplify the configuration of a Y/C separator circuit in which plural video signals comprising a reference signal and a signal subjected to time axis compression by a multiple of (n) are subjected to Y/C separation through the use of a CCD by varying a clock frequency with an input video signal so as to allow the device to cope with the input video signal compressed with a single CCD. CONSTITUTION:A signal changeover device 3 selects either a reference video signal (a) received from an input terminal 1 or a compressed video signal (d) received from an input terminal 2 respectively and the selected signal is directly inputted to a signal adder 5, and the selected signal is inputted as a video signal 16 to a CCD 4, in which the signal is delayed by one period of a horizontal synchronizing signal of the signal 16, the result passes through a filter in response to the input signal and is inputted to the adder as a delayed video signal 17. A chrominance signal is obtained from an output terminal 13 as an output of the signal adder 5 and a luminance signal is obtained from an output terminal 14 as an output of a signal subtractor 12. The time delayed by the CCD 4 is changed by using a signal selected by a clock signal changeover device 8 receiving an output of a reference frequency generator 6 and an output of a frequency multiplier 7 multiplying the frequency of the generator 6 by a multiple of (n), and then the configuration of the Y/C separator circuit for plural compressed video signals is simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus using a CCD for separating a video signal into a luminance signal and a chrominance signal.

[0002]

2. Description of the Related Art In recent years, the demand for digital video tape recorders has increased, and in particular, there has been an urgent need to improve the Y / C separation circuit using CCD elements.

In the prior art, in a device that separates a plurality of input video signals consisting of a reference video signal and a time-axis-compressed compressed video signal into a luminance signal and a chrominance signal, the reference frequency of the video signal is changed. For example, a separate circuit (hereinafter abbreviated as Y / C separation circuit) that separates a luminance signal and a chrominance signal is required each time, and a plurality of Y / Since the device requires a device including a C separation circuit, the device is complicated and expensive.

[0004]

However, in the above-mentioned conventional configuration, a Y / C separation circuit for separating the luminance signal and the chrominance signal for each different frequency of the compressed video signal is required, and a plurality of Y / C separation circuits are required. The device including the separation circuit has a problem that it tends to be complicated.

The present invention solves the above-mentioned problems of the prior art, and can change the period of the horizontal synchronizing signal of the input video signal, thereby complicating the apparatus even if the frequency of the video signal is a reference or is compressed by a positive multiple. It is an object of the present invention to provide a magnetic recording / reproducing apparatus that can separate a luminance signal and a chrominance signal without changing them.

[0006]

In order to achieve the above object, a magnetic recording / reproducing apparatus of the present invention uses a reference video signal in a signal processing process of a Y / C separation circuit for separating a luminance signal and a chrominance signal. And an input signal switcher for selecting a plurality of input video signals composed of compressed video signals that are time-axis compressed, a CCD for delaying one cycle time of a horizontal synchronizing signal of the video signals, and C
A reference frequency generator for generating a clock signal for driving a CD, a frequency multiplier for multiplying the reference frequency,
A clock signal switcher for switching between the reference frequency and the multiplied frequency, a signal adder for obtaining a color signal, and a CCD
It has a plurality of filters adapted to remove the clock signal that has driven, a filter switcher for switching each filter, and a signal subtractor for obtaining a luminance signal.

[0007]

According to the present invention, in the above-mentioned structure, even if the frequency of the video signal is a reference and the compressed video signal is a positive multiple thereof,
By switching the frequency of the clock signal that drives the CD to 1 and a clock signal that is a positive multiple of the frequency, both the reference video signal and the compressed video signal compressed to a positive multiple,
The signal processing unit of the Y / C separation circuit can be shared, and the Y and C signals can be separated from each other without complicating the device.
The configuration of the / C separation circuit can be greatly simplified.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, in the magnetic recording / reproducing apparatus of this embodiment, a reference video signal is input to an input terminal 1, and a compressed video signal which is time-axis compressed is input to an input terminal 2.
It is selected by the input signal switch 3 and added to the signal adder 5 and CCD 4. The outputs from the reference signal filter 9 and the compressed signal filter 10 are selected by the filter switcher 11 and added / subtracted by the signal adder 5 and the signal subtractor 12, respectively, and the color signal is output from the output terminal 13 and the luminance signal is output. Output from the output terminal 14. Here, when the input video signal is time-axis compressed to a frequency other than the reference frequency, the reference frequency generator 6, the frequency multiplier 7, and the clock signal switch 8
Therefore, the CCD 4 is driven by generating a necessary clock signal.

With respect to the magnetic recording / reproducing apparatus of the present invention comprising the above components, the relationship and operation of the respective components will be described with reference to FIGS. 1 and 2.

The reference video signal a is input from the input terminal 1 to the input signal switch 3 to be signal-selected to obtain the selected video signal 16 and then to the CCD 4 and the signal adder 5.

The selected video signal 16 is delayed by the CCD 4 for one cycle of the horizontal synchronizing signal of the reference video signal a, passes through the reference signal filter 9, and its output is the filter switcher 11.
To obtain the delayed video signal 17. The selected video signal 16 and the delayed video signal 17 are added in the signal adder 5,
A color signal like the reference color signal c is output from the output terminal 13.

The reference color signal c and the delayed video signal 17 are also input to the signal subtractor 12, the reference color signal c is subtracted from the reference video signal a internally, and a luminance signal as shown in the reference luminance signal b is output terminal. It outputs from 14.

Next, the output of the reference frequency generator 6 is selected by the clock signal switch 8 and is output by the clock signal 15 as C.
Drive CD4. Compressed video signal d that is time-axis compressed
Is input to the input signal switch 3 through the input terminal 2 to be signal-selected to obtain the selected video signal 16, which is then input to the CCD 4 and the signal adder 5.

The selected video signal 16 is delayed by the CCD 4 for one cycle of the horizontal synchronizing signal of the compressed video signal d, and passes through the compressed signal filter 10, the output of which is the filter switching unit 1.
1 to obtain the delayed video signal 17. The selected video signal 16 and the delayed video signal 17 are added in the signal adder 5 and a color signal as shown in the compressed color signal f is output from the output terminal 13.

The compressed chrominance signal c and the delayed video signal 17 are also input to the signal subtractor 12, where the compressed chrominance signal is subtracted from the compressed video signal internally, and a compressed luminance signal as shown in the compressed luminance signal e is output. It outputs from 14.

The output of the reference frequency generator 6 is input to the frequency multiplier 7 to double the frequency and then selected by the clock signal switch 8 to obtain the clock signal 15. Since the CCD 4 is driven by the clock signal 15, one cycle time of the horizontal synchronizing signal delayed by the CCD 4 is equal to the reference video signal a.
Is one half of the input of

[0018]

As is apparent from the above embodiments, according to the present invention, the frequency of the video signal is the reference and the time axis is the second.
Even with the doubled compressed video signal, the signal frequency of the Y / C separation circuit for separating the luminance signal and the chrominance signal can be shared by changing the clock frequency for driving the CCD to twice the reference frequency. Y / C that can be done and is complicated in the past
The configuration of the separation circuit can be simplified.

Further, even if the time compression of the compressed video signal becomes more than double, by simply changing the multiplication number of the frequency multiplier 7 and the filter for the compressed signal, it is possible to easily cope with it without complicating the apparatus. Thus, it is possible to realize an excellent magnetic recording / reproducing device capable of achieving the above.

[Brief description of drawings]

FIG. 1 is a block diagram of essential parts of a magnetic recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a main signal waveform diagram of the magnetic recording / reproducing apparatus.

[Explanation of symbols]

 3 Input Signal Switcher 4 CCD 6 Reference Frequency Generator 7 Frequency Multiplier 8 Clock Signal Switcher 9 Reference Signal Filter 10 Compressed Signal Filter 11 Filter Switcher

Claims (1)

[Claims] 1. A device for separating a video signal into a luminance signal and a chrominance signal by a CCD, and an input signal switcher for selecting a plurality of input video signals consisting of a reference video signal and a time-axis-compressed compressed video signal. A CCD for delaying the video signal selected by the input signal switcher by one cycle of the horizontal synchronizing signal; a reference frequency generator for generating a clock signal for driving the CCD; and a reference frequency multiplied. A frequency multiplier, a clock signal switcher for switching to a clock signal suitable for an input video signal, a plurality of filters suitable for removing the clock signal driving the CCD, and a filter switcher for switching each filter. Magnetic recording and reproducing device.