JPS62239781A - Reproducing and recording system for color video signal - Google Patents

Abstract

PURPOSE:To prevent a synchronizing from becoming out of phase by recording a color video signal in an excellent color framing state obtained by controlling the phase of a reproduced color video signal according to the color frame of a color frame decision signal on a recording medium. CONSTITUTION:The color video signal from a memory 6 and the color frame decision signal from a color frame extracting circuit 9 are supplied to an adder 18 as a composing means, whose output is supplied to the input terminal 20 of a recording-side VTR 2. The reproduced color video signal is written in a memory 21 and also read out, and relative control over the write and read clock frequencies of the memory 21 is carried out to control the quantity of the phase shifting of the read color video signal from the written color video signal with the comparison output of a color frame comparing circuit 26. Consequently, the memory 21 outputs a color video signal which fields or frames coincident with reference field or frames and is superior in color framing.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for reproducing and recording color video signals.

[Summary of the invention]

The present invention relates to a reproduction/recording method for a color video signal, and relates to a reproduced color video signal from a reproduction system whose field order is made to match the reference field order, and a color frame discrimination signal representing a color frame of the reproduced color video signal. is transmitted to the recording system, which controls the phase of the reproduced color video signal according to the color frame of the color frame discrimination signal to obtain a color video signal with correct color framing, and determines the correct color framing. By recording the color video signal on the recording medium, even if dubbing or electronic editing recording is repeated, there is no possibility that the phase of the synchronizing signal will be significantly shifted.

[Conventional technology]

A conventional example will be described below with reference to FIG.

In (1), the reproduction side VTR1 and (2) the recording side VTl≧. These VTRs (1) and (2) are connected to each other, and the reproduced color video signal obtained from the reproduction side VTR (1) is supplied to the recording side VTR (2) for dubbing or electronic recording.
Ifll recording is performed. In addition, these VTRs (1), (
2) both allow recording and reproduction and have similar configurations.

Next, the configuration of the reproduction side V"r"R(1) will be explained. TP is a magnetic tape on which FM-modulated color video signals (FM-modulated
A control signal (CTL signal) including a color frame discrimination signal is recorded in the longitudinal direction along the side edge thereof.

The FM modulated color video signal recorded on the magnetic tape TP is reproduced by a rotating magnetic head (3), and the reproduced FM modulated color video signal is reproduced by a reproduction amplifier circuit (
4) to the FM demodulation circuit (5). The color video signal obtained from the demodulation circuit (5) is stored in the memory (6
) is output to the output terminal (7). In addition, VTR (
When 1) is an analog VTR, the memory (6) is assumed to be equipped with an A/D converter and a D/A converter. If the VTR (1) is a digital VTR, these converters are not necessary.

The CTL signal including the color frame discrimination signal recorded on the magnetic tape TP is transmitted to the fixed magnetic head (8).
and is supplied to the color frame extraction circuit (9).

(14) is a synchronization separation circuit which separates the horizontal synchronization fa signal, vertical synchronization signal and color burst signal from the reference color video signal supplied to the input terminal (15), and based on these, field detection signal and color burst signal are separated. A frame detection signal is output.

(10) is a field comparison circuit, which compares the CTL signal reproduced from the fixed magnetic node (8) with the field detection signal obtained from the synchronous separation circuit (14).

Further, (13) is a color frame comparison circuit, in which the color frame discrimination signal obtained from the color frame extraction circuit (9) and the color frame detection signal obtained from the synchronization separation circuit (14) are compared. Ru.

The comparison outputs of these comparison circuits (10) and (13) are switched by a changeover switch (11) and supplied to a reel servo circuit (12) to select the inclined track when the magnetic tape TP1 is running. is controlled.

Thus, the rotary magnetic head (3) determines whether the odd-even of the field matches the odd-even of the field of the reference color video signal, or the odd-even of the frame matches the odd-even of the frame of the reference color video signal, according to the switching of the changeover switch (11). The FM modulated color video signal that matches the above is reproduced. This reproduced FM modulated color video signal is sent to the reproduction amplifier circuit (4).
The color video signal is supplied to the demodulation circuit (5) through the demodulation circuit (5) and demodulated, and the obtained color video signal is written to and read out from the memory (6). And this memory (6)
By relative control of the writing and reading clock frequencies of the color frame comparison circuit (13
) is controlled by the comparison output of the comparison circuit (13).
When a matching output is obtained, the phase shift amount is set to 0 degrees, and when a mismatching output is obtained, the phase shift amount is set to 180 degrees of the color subcarrier signal (color subcarrier frequency is 3.58 MH).
In the case of z, set it to 14Qnsec). The former phase shift amount is generally an even number multiple of 180 degrees (however, 0 is included), and the latter phase shift amount is generally an odd number multiple of 180 degrees.

Thus, from the output terminal (7), the field or frame matches the reference field or frame and the color framing is achieved (the phase of the carrier color signal matches the phase of the color burst signal of the reference color video signal). ) The reproduced color video signal is output.

This reproduced color video signal is recorded on the recording example VTR (2).
The signal is then FM-modulated as it is, and then dubbed onto another magnetic tape or electronically edited and recorded.

[Problem that the invention seeks to solve]

Such conventional color video signal reproduction/recording methods have the disadvantage that each time dubbing or electronic editing is repeated, the phase shift accumulates and becomes large, causing a significant shift in the phase of the synchronization signal.

In view of this, the present invention proposes a reproduction/recording method for color video signals that does not cause the phase of the synchronization signal to be significantly shifted even if dubbing or electronic editing/recording is repeated.

[Means for solving problems]

A color video signal reproduction/recording method according to the present invention includes a reproduced color video signal whose field order is made to match the reference field order from a reproduction system, and a color frame discrimination signal representing a color frame of this reproduced color video signal. is transmitted to the recording system, and in this recording system, the phase of the reproduced color video signal is controlled according to the color frame discrimination head color frame to obtain a color video signal with color framing, and this color framing is The obtained color video signal is recorded on a recording medium.

[Effect]

According to this misfire, the phase of the reproduced color video signal transmitted from the recording system to the reproduction system is not shifted, so even if dubbing or electronic editing is performed again, there is no possibility that the phase of the synchronizing signal will be significantly shifted. Become.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIG. (1) is the playback side VTR1 (2) is the recording side VTR
It is TR. These VTRs (1) and (2) are connected to each other, and a reproduced color video signal obtained from the reproduction side VTR (1) is supplied to the recording side VTR (2) for dubbing or electronic editing recording. Furthermore, these VTRs (1)
, (2) can both be recorded and reproduced, and can have a similar configuration.

Next, the configuration of the reproducing side VTR (1) will be explained.

TPl is a magnetic tape on which an FM-modulated color video signal (including a modulated FM audio signal) is recorded so that an inclined track is formed, and a color frame discrimination signal is recorded along the longitudinal direction on the side edge of the magnetic tape. A control signal (CTL signal) including the following is recorded.

The FM modulated color video signal recorded on the magnetic tape TP1 is reproduced by the rotating magnetic head (3), and the reproduced FM modulated color video signal is reproduced by the reproduction amplifier circuit (
4) to the demodulation circuit (5). Demodulation circuit (
The color video signal obtained from step 5) is supplied to memory (6). Note that when the VTR (1) is an analog VTR, the memory (6) is assumed to be equipped with an A/D converter and a D/A converter. VTR (1) is digital V
In the case of TR, these converters are not required.

The CTL signal including the color frame discrimination signal recorded on this magnetic tape TP1 is sent to the fixed magnetic head (8).
and is supplied to the color frame extraction circuit (9).

(14) is a synchronization separation circuit that separates a horizontal synchronization signal, a vertical synchronization signal, and a color burst signal from the reference color video signal supplied to the input terminal (15). Based on these, the field detection signal and color frame are separated. A detection signal is output.

(10) is a field comparison circuit, in which the CTL/i signal reproduced from the fixed magnetic field 7 (8) is compared with the field detection signal obtained from the synchronous separation circuit (14). Ru.

Further, (13) is a color frame comparison circuit, in which the color frame discrimination signal obtained from the color frame extraction circuit (9) and the color frame detection signal obtained from the synchronization separation circuit (14) are compared. Ru.

The comparison outputs of these comparison circuits (10) and (13) are switched by a changeover switch (11) and supplied to a reel servo circuit (12) to select the inclined trunk of the magnetic tape TP. Driving is controlled.

Thus, the rotary magnetic head (3) determines whether the odd-even of the field matches the odd-even of the field of the reference color video signal, or the odd-even of the frame matches the odd-even of the frame of the reference color video signal, according to the switching of the changeover switch (11). The FM modulated color video signal that matches the above is reproduced. This reproduced FM modulated color video signal is sent to the reproduction amplifier circuit (4).
The color video signal is supplied to the demodulation circuit (5) through the demodulation circuit (5) and demodulated, and the obtained color video signal is written to and read out from the memory (6).

Then, the color video signal from the memory (6) and the color frame discrimination signal from the color frame extraction circuit (9) are supplied to an adder (18) as a combining means.
The color frame discrimination signal is inserted into the vertical blanking section or an appropriate location of the color video signal, and the reproduced color video signal containing the color frame discrimination signal is outputted to the output terminal (7). When this color video signal is a digital signal, it is easy to insert this color frame discrimination signal.

Thus, from the output terminal (7), the field or frame coincides with the reference field or frame and contains the color frame discrimination signal (the phase of the carrier color signal is the same as the phase of the color burst signal of the reference color video signal). The reproduced color video signal (which may or may not match) is output.

Then, the reproduced color video signal including the color frame discrimination signal from the reproduction side VTR (1) is transferred to the transmission line (19).
) is supplied to the input terminal (20) of the recording side VTR (2).

In the recording side VTR (2), a reproduced color video signal including a color frame discrimination signal from an input terminal (20) is supplied to a memory (21), a color frame separation circuit (22), and a sync separation circuit (23). .

The color frame separation circuit (22) separates the color frame discrimination signal from the reproduced color video signal input thereto. Further, the synchronization separation circuit (23) separates horizontal and vertical synchronization signals and color burst signals from the reproduced color video signal input thereto, and outputs a color frame detection signal based on these signals. Then, the color frame discrimination signal from the color frame 4 separation circuit (22) and the color frame detection signal from the sync separation circuit (23) are supplied to a comparison circuit (26) and compared.

Also, the reproduced color video signal is written to and read out from the memory (21). And this memory (
By the relative control of the write and read clock frequencies in 21), the amount of phase shift of the read color video signal with respect to the write color video signal is controlled by the comparison output of the color frame comparison circuit (26), and this comparison circuit (
26), the amount of phase shift is set to 0.
degree, and when a mismatched output is obtained, the phase shift amount is set to 180 degrees of the quick-open 1 general transmission signal (color subcarrier frequency is 3 degrees).
In the case of 58 MHz, it is set to 140 nsec). The former phase shift amount is generally an even number multiple of 180 degrees (however, 0 is included), and the latter phase shift amount is generally an odd number multiple of 180 degrees.

Thus, at the output side of the memory (21), a field or frame is displayed which corresponds to the reference field or frame and whose color framing has been achieved (the phase of the carrier color signal is equal to the phase of the color burst signal of the reference color video signal). A color video signal (matching the color) is output. This color video signal is supplied to the modulation circuit (30) and subjected to FM modulation, and this FM modulated color video signal is supplied to the recording amplifier circuit (24).
) is supplied to the rotating magnetic head (25), and the FM-modulated color video signal is recorded so as to form an inclined track on the magnetic tape TP2.

Further, the color frame discrimination signal from the color frame separation circuit (22) is supplied to an adder (28) as a combining means, where it is added to the CTL signal from the input terminal (27), and this color frame discrimination signal is The CTL signal containing the magnetic tape TP2 is supplied to the fixed magnetic head (29) and
recorded along its longitudinal direction on the side edges of the

Note that the above-mentioned VTRs (1) and (2) may be analog VTRs or digital VTRs.

〔Effect of the invention〕

According to the present invention described above, it is possible to obtain a reproduction/recording method for color video signals in which there is no possibility that the phase of the synchronization signal will be significantly shifted even if dubbing or electronic editing/recording is repeated.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional system. (1) is a reproducing side VTR; (2) is a recording side VTR.

Claims (1)

[Claims] A reproduced color video signal whose field order is made to match the reference field order and a color frame discrimination signal representing a color frame of the reproduced color video signal from the reproduction system are transmitted to the recording system, and the recording system , controlling the phase of the reproduced color video signal according to the color frame of the color frame discrimination signal to obtain a color video signal with color framing, and recording the color video signal with color framing on a recording medium. A color video signal playback/recording method characterized in that: