JPS59226591A - Color video signal recording and reproducing device - Google Patents

Abstract

PURPOSE:To correct phase deviation between color signal and luminance signal in a recording and reproducing device that componentially records color video signal by changing the distance between a color signal head and luminance signal head at the time of recording and reproducing. CONSTITUTION:A head 45 for luminance signal has two gaps 45A and 45B formed at specified distance, for instance 2H. The first gap 45A is provided at a position off from a gap 46A of a head 46 for color signal by a distance X in the direction of rotation (a) of a drum 47. The gap 45B is provided at a position off from 45A by the distance 2H in the direction reverse to the direction of rotation (a) of the drum 47. The gap 45A constitutes a head 41 for luminance signal recording, and the gap 46A constitute head 42 and head 44 for color signal recording and reproducing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color video signal recording and reproducing apparatus, and is particularly applicable to recording components of color video signals.

[Background technology and its problems]

Conventional video tape recorder (VTR) uses a component recording system that improves reproduced image quality by recording and reproducing the luminance signal Y and color signal C1 as component signals constituting a color video signal on separate tracks.
℃, the configuration shown in Figure 1 has been proposed.

In this type of VTR, the frequency band of the color signal C is the luminance signal Y.
The color signal C
By compressing the time axes of the color difference signals (R-Y) and (B-Y) contained in
One multiplexed color difference signal (R-Y) and (B-Y) having almost the same frequency band is obtained, and this multiplexed color difference signal (R
-Y) and CB-Y) are recorded on one track to increase the recording density on the retape.

That is, during recording, the input video signal S1 is input to the recording circuit section REC.
/l'r/'C5+separated into a chrominance signal C and a luminance signal Y in a separation circuit 1, and the luminance signal Y is combined with a synchronization signal 5YNC in a recording circuit 2 and sent to the first video head 3 for recording the luminance signal. is recorded on the first track of tape 4 by. On the other hand, the color signal C is separated into color difference signals R-Y and B-Y by the color signal decoding circuit 5 and is applied to the time axis compression multiplexing circuit 6. The time axis compression multiplexing circuit 6 converts the color difference signals R-Y and B-Y into digital codes by the analog-to-digital conversion circuits 7 and 8, respectively, and stores them in the memories 9 and 10 line-sequentially for one horizontal opening period (this After writing each stored data in the first half and the second half of the IH section of the person (referred to as the IH section), each stored data is read out at twice the writing speed and is sent to the synthesis circuit 1.
1, and the digital-to-analog conversion circuit 12
By outputting the signal through 11, the multiplexed color difference signal (R-Y)/(B
-Y) is obtained. This multiplexed color difference signal (RY) −(B
-y) is combined with the synchronizing signal 5YNC in the recording circuit 13 and recorded on the second track of the tape 4 by the second video head 14 for recording color signals.

Here, the first and second heads 3 and 14 are each a pair of video heads (so-called A, B), as shown in FIG.
head), a stand, and a second head 1 for signal recording.
4 is mounted on a rotating drum 15 at a distance X of h degrees from the first head 3 for recording luminance signals.

Comparing the phases of the multiplexed color difference signals (R-Y) and (B-Y) recorded on the tape 4 by the heads 3 and 14 with the phase of the luminance signal Y, FIG. As shown, the phase is delayed by I14. That is, the input video signal S1 to the Y/C separation circuit l has a third
The luminance signal Y (Yn, Yn+1.Yn, 2...
. . .) arrives at the next Jim in the 111th section, as shown in Fig. 3 (J3) and C), the difference between the two cars is synchronized with this ((R-Y)11. R-Y)n+1
．． (RY'n+2-...) and (B-Y)(
CB-Y) , (B-Y) , (B-Y)n+
2...) arrive n n+1, so it can be considered that there is no phase shift between the luminance signal Y and the color difference signals R-Y and B-Y.

On the other hand, in the compression multiplexing circuit 6, the color difference signal R-Y
, B-Y is concatenated on the time axis, the color difference signal for IH (
R-Y) and (B-Y)n, (R-Y)n+1 and (B-Y)n+1, (R-Y)n+2 and (B
−Y)n+2... The multiplexed color difference signal corresponding to (
l<.

-Y)n@(B-Y)n, (RY)n+1・
(B”n+1゜(RY)n+2・(RY)n+2・
... are read out from the memories 9 and 10 of the compression multiplexing circuit 6, as shown in FIG.
The phase is delayed by iH compared to the timing at which the signal arrives at the recording circuit 2, and the signal is recorded on the tape 4 with this phase delay.

In this embodiment, the luminance signal Y and the multiplexed color difference signals (l(-Y) and (13-Y)) recorded as components on the tape 4 are reproduced by the same video heads 3 and 14, respectively, and the reproduction circuit section PBC After regeneration - circuit 2
1 and n. The reproduced variable signal Y is modulated in the reproduced demodulator circuit 21, and the reference synchronization signal 41 REFSYNC
Based on this, the time axis correction circuit corrects time axis fluctuations such as jitter, and then the signal is applied to the delay circuit. Of course, the delay circuit delays the luminance signal Y by 2H and then supplies it to the synthesis circuit 6.

On the other hand, reproduced multiplexed color difference signal (RY)/(B-Y
) is encoded into digital double@ by the analog-to-digital conversion circuit 27 of the time axis correction expansion circuit and converted to IH.
They are written to the memory path line by line. In this way, the memory path contains 1247 minutes of data compressed into the first half.
The color difference signal R-Y for two inches is stored, and the compressed color difference signal B-Y for one line is stored in the latter half. Then, in the next IH interval, the data stored in the front and rear parts are outputted simultaneously at a convolution speed of Imabo Σ based on the reference synchronization signal REFSYNC, and then jitter etc. are removed as necessary. The time axis fluctuation force Kusunoki 11 is corrected, and the digital to analog conversion circuits 29 and 30 are respectively
The encoded color signal C is supplied to the color signal encoding circuit 31 through the color signal C, and the encoded color signal C is supplied to the synthesis circuit section.

In addition to this, the synthesis circuit section has a violent four-phase signal REFSYN.
C is supplied, and the output video signal S2 is combined IJy with the luminance signal Y and the chrominance signal C.

Comparing the phases of the reproduced color difference signals R-Y and B-Y sent out from the time axis correction and expansion circuit in this way with the phase of the reproduced luminance signal Y obtained from the time axis correction circuit, we get:
As shown in FIG.
is reproduced with a phase that is 18 minutes ahead of lj), while the reproduced color difference signals R-Y and B-Y are As shown in Figures 3 and 3, the multiplexed color difference signal (R-Y)
Since it has a phase delayed by IH with respect to (B-Y), the phase of the reproduced color difference signal 1 (-Y and H-Y is 2H minutes ahead of the reproduced luminance signal Y). .

Incidentally, at the time axis correction circuit station, the reproduced color difference signal for IH <IR-Y)n, (RY)n+1,
(R”) n+2” song and (B-Y)n, (B-Y
)n,i.

(B-Y)n+□...The songs are from memo 1j28,
Multiplexed color difference signal (R-Y) n+1- (B-Y) n+
t, (RY)n+2-(B"n+2...
This is because the data will be read out at the timing of .

In the case of the conventional configuration shown in FIG. 1, the phase advance of the reproduced color difference signals R-Y and B-Y by 2H with respect to each reproduced luminance signal Y is caused by delaying the phase of the reproduced luminance prime signal Y by 2H in the delay circuit SAE. The phase of the color signal C of the output video signal S2 sent from the combining circuit 5 matches the phase of the luminance 4M@Y, and thus K can be adjusted to prevent color shift.

In this way, by changing the reading speed when reading out the color difference signal as a component signal from the memory, the color difference signal 'I! 0'u? F1) In the color bidet No. 141 recording and reproducing device that compresses the axis and expands the length of m1 per hour,
In principle, when compressing and expanding the time axis, it is inevitable that the phase of the color difference signal with respect to the luminance signal will be delayed by IH (total of 2H). To correct this phase shift, the delay is applied as shown in Figure 1. If the circuit 24 is used, the luminance signal Y having a relatively wide frequency band must be delayed by a relatively long time 1 (that is, about 21 (=130 CμS)), so the configuration of the delay circuit U becomes large. In addition, there are problems such as deterioration of the frequency characteristics of the luminance signal Y, deterioration of temperature characteristics, and deterioration of changes over time.

[Purpose of the invention]

The present invention has been developed in consideration of the above points, and is intended to effectively compensate for the phase shift of 2H by using a relatively easy configuration without using a delay circuit.

[Summary of the invention]

In order to achieve this object, in the present invention, the reproduction luminance of the reproduced color signal (in the position 4 with respect to the 5 are used as the video heads 41, 42 for distributing signals, variable signals, and color signals, as well as the video heads 43, 44 for reproducing luminance signals and No. 16. That is, the head 45 for luminance is pJ. [There are two gaps 7° 45A and 45B formed apart from each other by a certain distance, for example, 2H.The gap 45A of the head 1 is in the direction of rotation of the drum 470 with respect to the gap 46 A K of the color signal head 46. The second cap 45B is disposed at a distance X apart from the drum 470 with respect to the first gap 45A.
It is arranged at a position separated by a distance of 2H in the opposite direction to the rotary blade rotation a. Thus the first gap 4 of the head 45
5A is the brightness in FIG. 4 (comprising the fi number recording head 41, the second gap 45B of the head 45 is the luminance part 43 of FIG. 4, and the gap 46AIJ''- Color signal recording and reproducing head 4 in Fig. 4
2 and 44.

Here, in principle, the distance X between the gap 46A of the chrominance signal head 46 and the first gear tooth 45A of the luminance signal head 45 is selected to be equal to the distance 1j11X between the heads 14 and 3 in FIG. On the other hand, as described above, the distance between the first and second gaps 45A and 45B of the brightness signal head 45 is selected to be a distance corresponding to two horizontal opening periods 2H.

Further, the rotation direction a of the rotating drum 470 is one of the brightness signal head 45 and the color signal head 46, as in the case of the WJ2 diagram.
The first gap 45A of the brightness signal head 45 is advanced by a phase corresponding to the distance X with respect to the gap 46A of the color head 46. The second gap 45B of the i head 45 is at an electrical position delayed by the phase of 2H with respect to the gl gap 45A (if m'Th The position of the gap 46A of the color signal head 46 with respect to the second gap 45B is 2H from the first gap 45A.
This indicates that the ball is at a mountainous position (X-2H), which has advanced by 4+.

In addition to the above configuration, the reproduction circuit section PBC of this embodiment is similar to that in FIG. 1 with the delay circuit 24 omitted, as shown in FIG. It has a configuration. In FIG. 4, the recording circuit section 1c is constructed in exactly the same manner as in FIG. 1.

In the above configuration, recording of each luminance number Y is performed using the first gap l15A of the luminance signal head 45. In this way, as is clear from FIG.
gaps 45A and 46 while rotating in the direction of arrow a.
A respectively uit=signal Y and multiplexed signal (i
t-Y).(B-Y) is recorded on the tape 4. Thus, on the tape 4, as shown in FIG. 6a), there are multiplexed signals (R-Y) and (B-y) whose phase is delayed by IH with respect to the KSTE degree signal transformation (FIG. 6(4))K. is recorded.

The luminance signal Y and the multiplexed difference signal (
R-Y) and (B-Y) are reproduced by the second gap 45B of the h-degree program head 45 and the color signal head 46, respectively. At this time, the second gap 45B is at a position delayed by a phase of 2H with respect to the first gap 45A, so who can look at the color signal head 46 based on this first gap 45B? The phase of the reproduced multiplexed color difference signals (R-Y) and (B-Y) is the 6th (
9) As shown in (2), the phase advances by 2H compared to the case of recording (FIG. 6, 0).

The machine difference signal R-Y is expanded from the reproduced multiplexed color difference signals (R-Y) and (B-Y) by the time axis correction expansion circuit station.
and B-Y are delayed by the phase of IH with respect to the multiplexed difference signals (RY) and (B-Y)K, as shown in FIG. 6 and 0. As a result, the phase of the color signal C supplied to the combining circuit 5 matches the phase of the luminance signal Y supplied to the combining circuit 5.

In this way, when compressing, multiplexing, expanding and separating the color difference signals R-Y and B-Y, the electrical 4C2H is used based on the luminance signal Y.
However, the color signal head 46
By changing the arrangement relationship between the brightness signal head 45 and the brightness signal head 45 during recording and reproduction, the electrical phase delay can be effectively corrected.

FIG. 7 shows another embodiment of the present invention. In this case, even if there is a mounting error in the heads 45 and 46 when the heads 45 and 46 are positioned, this is corrected by an electrical phase adjustment circuit 51. As a result, the color difference number Rx' can be determined with a practically sufficient precision (for example, within several μm3).

The processing is performed so that the phase of B-Y with respect to the luminance signal Y can be matched.

In this case, the second gap 45B of the brightness signal head 45
is formed at a position delayed by a phase of 2H+Q with respect to the first gap 45A, as shown in FIG. 8, corresponding to FIG. 5, and as shown in FIG. 7, corresponding to FIG. A delay t'v@ adjustment circuit 51 is inserted at the output end of the time axis correction and expansion circuit 26 of the reproducing circuit PHC. Here, the position f adjustment jii'a is the maximum allowable installation error, for example, several [μm
] is selected, and therefore reproduced color difference signals R-Y, B- are reproduced by the gap 45B of the head 45.
As shown in Figure 9 Q3) and (C) Ic, the electrical phase of Y always leads the phase of luminance A and r@y (Figure g (4)) (even if there is an installation error) ). Thus, it is assumed that the phase of the reproduced color difference signals R-Y and B-Y at the output end of the time axis correction/expansion circuit 51 is advanced by an amount corresponding to the adjustment angle β including the mounting error (Fig. 9).
) and (C)), this β is adjusted by the leech-prohibition automatic adjustment circuit 51 so that β=OK (FIG. 9, 0 and
).

As shown in FIG. 10, the delay amount automatic adjustment circuit 51 receives the reproduced color difference signals R-Y and B-Y of the time axis correction and expansion circuit at Tl11 control delays -52 and 53, respectively, and outputs the output signals 84 and S5. Color signal encoding circuit 31
&C Send. The output signal S5 of one of the controllable delay lines 52 or 53, for example, Sho, is compared with a reference phase signal S6 in a phase comparison circuit 54, and the comparison output S7 is given to the controllable delay line 52 and 53 as a delay amount control signal, Thereby, the delay amounts of the controllable delay lines 52 and 53 are controlled so that the phase difference represented by the comparison output 87 is OK.

Here, the reference phase signal S6 is set to a value corresponding to the phase of the luminance No. 43 Y, and thus the outputs of the delay lines 52 and 53 are reproduced color difference signals R-Y, B- including the mounting position error of the heads 45 and 46. The electrical phase of Y is electrically corrected so as to match the phase of Y of luminance 4n. After all, Figure 7 ~ 1
According to the configuration shown in FIG. 0, the electrical phase can be adjusted with sufficient precision even if the heads 45 and 46 are not positioned with perfect precision.

Since the phase of the color signal C is adjusted by the controllable delay lines 52 and 53 with K, it is possible to effectively eliminate the possibility of deterioration of its frequency characteristics. Incidentally, this is because the chrominance signal C has a narrower "c111i1 wave number band" than the luminance signal Y.

In the above description, the two gaps 45A and 45B are provided in the luminance signal head 45, and the color difference signal head 46 and the color difference signal head 45 are used during reproduction and recording.
Although the distance #1 between them is changed, instead of this, two gaps may be provided in the color signal head 46.

Furthermore, in the above description, the color difference signal RY is used during reproduction.

The phase of B-Y was adjusted to IMI by changing the head position, but instead of this, when recording, the phase of the combined signal R-Y,
The phase of HY may be advanced.

〔Effect of the invention〕

As described above, according to the present invention, by changing the interval between the color signal head and the luminance signal head during recording and reproduction, the phase between the color signal and the luminance signal that occurs when compressing and expanding the color difference signal is The deviation can be effectively corrected by a simple structure jJy that does not use a mongrel-type delay circuit.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing a conventional color video signal recorder equipment, Figure 2 is a route diagram showing the arrangement and configuration of its head, and Figure 3 is a signal showing the phase relationship of the signals of each part in Figure 1. Figure 4 is a block diagram showing an example of a color video recording and reproducing equipment according to the present invention, Figure 5 is a route map showing the arrangement of its heads, and Figure 6 is a diagram showing each part of Figure 4. (Fig. g, Fig. 7 is a block diagram showing another embodiment of the present invention, Fig. 8 is a route map showing the arrangement and configuration of the head, and Fig. 9 is the same as Fig. 7). Figure 10 is a block diagram showing the specific configuration of the automatic delay adjustment circuit shown in Figure 7. 1...Y/C separation circuit, 2 .13...recording circuit, 3
・14...-Head, 5...Baigi number decoding circuit,
6... Time axis compression multiplexing circuit, 9.10... Memory, 11... Synthesizing circuit, 21.22... Reproduction demodulation circuit, Ru... Time axis correction circuit, Sae... Delay Circuit, Z5・
...Synthesis circuit, time axis correction expansion circuit, measurement...
Memory, 31... Color 1J encode circuit, 41,
43, 45... Brightness signal head, 42, 44
, 46...Head for joint number J, 51...-N extension automatic adjustment circuit, it E C...recording circuit section, PBC.
...Regenerated 1 μm road section. Applicant's agent 1) Kei Hajime

Claims (1)

[Claims] The input video signal is separated into a luminance signal and a chrominance signal, which are component signals, and the luminance signal is recorded on a first track by a luminance signal head, and the chrominance signal is compressed and multiplexed, and recorded on a second track by a chrominance signal head. During playback, the distance between the chrominance signal head and the luminance signal head is changed by the phase corresponding to the number of horizontal sections, and the first track is recorded by the luminance signal head. Obtaining an output video signal by combining a luminance signal obtained by scanning and a color signal obtained by expanding and separating a compression multiplexed signal obtained by scanning with the color signal head of the second track. A color video signal recording and reproducing device characterized by: