JPS6235795A - Recording and reproduction system - Google Patents

Abstract

PURPOSE:To approximate and correct a time-base variation correcting signal as compared with conventional signals by putting the 2nd horizontal synchronizing signal in the phase part of a 1/2 horizontal line behind a horizontal synchronizing signal in addition to the signal and adding a time-base correcting signal generated from the 2nd horizontal synchronizing signal to a time-base correcting signal. CONSTITUTION:The 2nd horizontal synchronizing signal 2 extracted from a playback color difference signal is inputted to a phase comparator 9. A horizontal reference synchronizing signal having no time-base variation is delayed by a 1/2 horizontal time phase through a 1/2 horizontal time delay multivibrator circuit 8 and inputted to the phase comparator 9. Its phase is compared with the phase of the 2nd horizontal synchronizing signal 2 and a time-base correcting signal is sent to an adding circuit 7 through a gate circuit 11 and added to said correcting signal 6 to generate the more approximate time-base variation correcting signal 12. The quantity of time-base variation of a B-Y signal after correction is reduced to a half as large as that of a conventional system.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a recording and reproducing method, and more particularly to a recording and reproducing method for reducing time axis fluctuations of color signals in recording and reproducing component signals.

(Prior art and its problems) A component signal recording method is used in recent ENG camera-integrated recording and reproducing devices. For example, a video signal is divided into a luminance signal and a color difference signal (RY signal, B
-Y signal), and the time axis of the RY signal and the BY signal is compressed to 1/2.

Each horizontal line is time-divided into one signal.

One field period of the luminance signal is compressed on the time axis into one track, and one field period of the color difference signal divided into nine times is compressed into one track.
track and record it on a recording medium. Figure 2(a)
shows one horizontal line of the luminance signal in the Color Par signal, and (b) shows an example of the waveform of one horizontal line obtained by time-base compression of the color difference signal in the Color Par signal.

As shown in the waveform (b), the horizontal synchronizing signal 1 is inserted at the beginning of the RY signal. The horizontal sync signal is 0 during playback.
In addition to being used as a 1-hour information signal when passing a reproduced signal with time axis fluctuations through a time axis fluctuation corrector to remove time axis fluctuations, it is also used as a 1-hour information signal to extend the time axis of the reproduced signal again and return it to the original time axis. It becomes a reference signal. The horizontal synchronization signal also serves as a reference signal when performing phase adjustment so that the luminance signal and color difference signal match in phase.

However, conventionally, as shown in FIG. 2(b), after time division.

There was only one time information signal per horizontal time.

FIG. 4 shows a correction signal detection section for the time axis corrector.

The horizontal synchronization signal 3 extracted from the reproduced color difference signal is phase-compared with a horizontal reference synchronization signal 4 whose time axis is stable, in a phase comparator 5, and the one time axis variation is sent as a correction signal 6 to the time axis corrector.

As shown in FIG. 2(b), since the horizontal synchronization signal 1 is present only at the start time of the R-Y signal, time axis fluctuations are detected at this time, and a correction signal is created and sent to the time axis corrector.
The time until the next horizontal synchronization signal is approximately corrected on the assumption that the time axis fluctuation of the reproduced signal is linear and does not change.

This method compresses the time axes of the R-Y and B-Y signals for recording and playback, and then expands the time axes in the playback signal processing circuit to return them to the original time axes, which eliminates time axis fluctuations. The size of is time axis compression.

Compared to a normal recording/reproducing device that does not perform decompression, the time axis fluctuation is twice as large as that on the screen.

In the waveform shown in Figure 2 (b), the time axis fluctuation is corrected using the horizontal synchronization signal, so the time axis fluctuation is very small for a short time after the synchronization signal, but the time up to the first horizontal synchronization signal is Since the correction signal is approximated to the fact that the time axis variation of the reproduced signal is linear and does not change, there is a drawback that the time axis variation that is not corrected becomes larger as time passes.

(the purpose) The purpose of this invention is to eliminate the above drawbacks as much as possible.

In addition to the conventional horizontal synchronization signal, a second horizontal synchronization signal is added to the phase portion of the horizontal line after that signal.

A time axis correction signal generated from the second horizontal synchronization signal is added to the conventional time axis correction signal, so that the nine time axis variation corrector signals can be more approximately corrected than the conventional one.

(Example) FIG. 3 shows the color difference signal waveform used in this invention.

It is the same as before that there is a horizontal synchronizing signal 1 before the beginning of the R-Y signal, but a second horizontal synchronizing signal is present after the station horizontal line from this synchronization, that is, before the beginning of the B-Y signal. Horizontal synchronization signal 2 is input. The time axis correction signal created by the horizontal synchronization signal and the horizontal reference synchronization signal is the second one after the % horizontal line.
By adding a time-base correction signal made from the horizontal synchronization signal and the horizontal reference synchronization signal delayed by the horizontal line, it is possible to create a time-base variation correction signal that is approximately corrected compared to the conventional method.

Embodiments of the present invention will be described below with reference to FIG. 3 and FIG.

FIG. 3 shows the waveform of the color difference signal used in this invention.

Before the beginning of the R-Y signal is a conventionally used horizontal synchronization signal. A second horizontal synchronizing signal 2 is newly added at a phase position after the horizontal line from this synchronizing signal, that is, before the beginning of the B--Y signal. After recording, the following processing is performed during playback.

FIG. 1 shows a configuration diagram of a color difference signal time axis variation detector according to the present invention. The phase comparator 5 generates a time axis correction signal 6 from the horizontal synchronization signal 3 extracted from the reproduced color difference signal and the horizontal reference synchronization signal 4 with no time axis fluctuation, and the time axis correction signal 6 is generated by the adder circuit 7 as a time axis fluctuation correction signal 12. Axis variation compensator (
(not shown). At this time, the gate circuit 11 is disconnected.

The addition signal from the phase comparator 9 does not come to the addition circuit 7.

The operation up to this point is similar to the conventional method.

Next, the second horizontal synchronization signal 2 extracted from the reproduced color difference signal
enters the phase comparator 9. Further, the horizontal reference synchronization signal 1 4, which has no time axis fluctuation, enters the phase comparator 9 whose return horizontal time phase is delayed by the horizontal time delay multivibrator circuit 8. Here, the phase of the second horizontal synchronization signal 2 is compared with the previous second horizontal synchronization signal 2, and the time axis correction signal 9 is sent to the adder circuit 7 via the gate circuit 11 and added to the previous correction signal 6, resulting in a more approximated time axis fluctuation correction signal. You can make 12. Compared to the conventional method, there is a possibility that the amount of time-axis fluctuation of the corrected BY signal can be significantly reduced.

Note that the gate circuit 11 is driven by the gate pulse 10, but the gate circuit 11 is disconnected from the horizontal synchronizing signal 1 to before the second horizontal synchronizing signal 2, and from the second horizontal synchronizing signal 2 to the horizontal synchronizing signal 1. The gate circuit 11 is in a conductive state until .

The horizontal synchronization signal 1 is the time information signal of the R-Y signal.

It is also possible to use the second horizontal synchronization signal 2 as the time information signal of the B-Y signal to create time axis fluctuation correction signals for each, but in this case, the R-Y signal and the B-Y signal each have a time This requires an axis variation corrector (time pace corrector) and becomes uneconomical.

(Effects) In this invention, as in the prior art, a more approximate signal can be obtained by using one time axis variation corrector for the color difference signal and creating a correction signal for each false horizontal line.

As mentioned earlier, this recording/reproducing method expands the time axis of the reproduced signal after reproduction, so the influence of time axis fluctuations becomes a problem. Making the time axis variation correction more approximate reduces the time axis variation after correction (and improves the performance of the image signal.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, and FIG. 2 is a waveform diagram of an example of a conventional component signal, in which (a) is a luminance signal;
(b) is a time-base compressed/time-division chroma signal. FIG. 3 is a waveform diagram of a time-base compressed/time-division chroma signal used in the present invention, and FIG. 4 is a configuration diagram of a conventional time-base variation correction signal detection section. 1: horizontal synchronization signal, 2: second horizontal synchronization signal. Contains: horizontal synchronization signal (TAPE) extracted from the reproduced color difference signal
H), 4: Horizontal reference synchronization signal (REF H), 5:
Phase comparator, 6: time axis fluctuation correction signal, 7: addition circuit. 8: Horizontal time delay multi-circuit, 9: Phase comparator. 10: Gate pulse, 11: Gate circuit, 12: Time axis fluctuation correction signal.

Claims (1)

[Claims] The video signal is divided into a luminance signal and two chrominance signals, and one field period of the luminance signal is divided into one track, and the two chrominance signals are
The time axis of the two color signals is compressed to 1/2, and each horizontal line is time-divided into one signal, and the signal of one field period is recorded on a track separate from the track of the luminance signal. In the reproduction method, a synchronization signal (
1. A recording and reproducing method characterized in that a time information signal (time information signal) is input and recorded, the same is reproduced, and the time axis fluctuation is corrected using the synchronization signal.