JPS6080391A - Recording and reproducing system of video signal by line sequentiality - Google Patents

Abstract

PURPOSE:To realize a recording/reproducing system of a line sequential color video signal eliminating a color error at the reproducing side by delaying one color difference signal for 1H period ahead the application of line sequentiality of two kinds of color difference signals. CONSTITUTION:A luminance signal Y is fed to an input terminal 11, color difference signals R-Y and B-Y are inputted respectively to input terminals 12, 13 and a control pulse PC whose state is changed at each 1H is fed to an input terminal 14 respectively. The color difference signals R-Y and B-Y are fed to a line sequential switch 17, the one B-Y signal is delayed by 1H at a 1H delay circuit 21 before line sequential processing. Moreover, the color difference signals R-Y and B-Y are selected alternately at each 1H by the control pulse PC and fed to an FM modulator 18 as a line sequential color difference signal. The carrier color difference signal from the FM modulator 18 is multiplexed with a carrier luminance signal at a mixer 16 and given to a recording head 20 as a carrier video signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The system has been devised to eliminate color errors on the reproduction side.

In France and other countries, a television system called the SECAM system has been standardized. In this SECAM force formula, 2
two color difference signals R-Y, B-Yki horizontal scanning period (hereinafter referred to as I
A line sequential switch is used to alternately switch and select the subcarriers for each subcarrier (abbreviated as H period), frequency modulate each subcarrier with two subcarriers, and superimpose it on the luminance signal to form a carrier video signal. The IH period was delayed on the reproduction side of this broadcasting video signal (
No. 43 and other signals in parallel (by taking out the color difference signals RY, B-Y'e thinned out every IH period and supplementing them to create two continuous color difference signals RY, B-Y) For this reason, a switch is provided on the reproduction side to alternately output the signal delayed by the LH period and the signal delayed by the LH period.In this way, two types of color difference signals are output in parallel. The process of taking out the data is called synchronization, and the switch for this purpose is called a full synchronization switch.

FIGS. 1(a) to 1(e) are explanatory diagrams conceptually showing the structure of each color difference bucket in the line sequential method.

In the same figure, the zafix attached to Y is the color difference signal R,
-Y, BY indicates the number of the horizontal scanning line to which Y belongs, and one block indicates an IH period. The color difference signals R-Y and B-Y shown in FIGS. 1(a,) and 1(b) are alternately selected every IH period by a line order normalization switch and are shown in FIG. 1(c). The line sequential color difference signal RY' shown in FIG.

B-Y'. Line sequential color difference signal RY' in this case
.

B-Y' is selected to belong to an odd-numbered IH period for the color difference signal R-Y, and one belonging to an even-numbered IH period for the i-signal B-Y.
-Y' is a synchronization switch that synchronizes the IH period delayed and non-IH period delay on the playback side.
Two types of simultaneous color difference signals R-Y" and B-Y" shown in FIG. 1(d) and FIG. 1(e) are obtained.

In such a line sequential method, as is clear from FIG. 1 (dl and FIG. 1 fe), the synchronized color difference signal R-
The signal belonging to the even-numbered IH period for the synchronized color difference signal B-Y" and the odd-numbered IH period for the synchronized color difference signal B-Y" are on the line 71111.
Next color difference signals R-Y', B-Y' are converted to 1'l-1 period)J
The signal is obtained with a delay. Therefore, I that is in contact with II
There is no problem if there is a phase difference between the color difference signals R-Y and B-Y in each H period, but the color difference signal R-Y in one IH period and the next IH period.

If B-Y changes significantly, a color that is significantly different from the original color will be reproduced. For example, color difference signals R-Y, B-Y belonging to the third IH period.

If the color difference signal R-Y, , B-Y4 belonging to the fourth one changes greatly, the simultaneous color difference signal R-Y, ", B-Y" corresponding to the fourth one becomes the color difference signal R-Y, .

Since the signal is B Y4, a color error occurs when the color difference signal RY is reproduced.

FIG. 2 is a block diagram showing an example of a conventional technique in which all aspects of reproduction are devised to reduce the color error. As shown in the figure, the synchronization switch 1 includes a switch 2 that outputs the synchronized color difference signal RY'' and a switch 3 that outputs the synchronized color difference signal B y//=. Contact 2a
, 2b, and the switch 3 has contacts 3a and 3bk, respectively, and a control pulse p c is applied so that the contacts 2a and 3b are simultaneously selected, and the contacts 2b and 3a are simultaneously selected, respectively.
The switch 2 is switched directly, and the switch 3 is inverted by an inverter 4 and switched every IH period. Contacts 2a, 3
alC is connected to D2H by two IH period delay circuits 5.6.
period-delayed 7c line sequential color difference signal R-Y';
Line sequential color difference signal R-Y' directly supplied with B-Y'
, B-Y' and output are reduced to 1/2 by a mixer 7 (a mixed color difference signal! Nidoshi-(2HDL)
-, and the line sequential color difference signals R-Y' delayed by the IH period by the IH period delay circuit 5 are also applied to the contacts 2b and 3b.
, B-Y' are supplied, respectively.

FIG. 3(1,) to FIG. 3(d) show the synchronized color difference signal R for the color difference signals R-Y and B-Y in the prior art described above.
FIG. 3 is an explanatory diagram conceptually showing the structures of -Y" and B-Y" in consideration of their temporal relationships. Referring to the figure, it is clear that the synchronized color difference signal R-Y" is the color difference obtained by dividing the sum of the color difference signal R-'Yn-+ from 2H period ago and the current color difference signal R-Yn by 2. Faith (R-Yn C+(R-Yn-z
) After No. □, the color difference signal R-Yn before the IH period at that point in time (R-Yn+r)
Then, this relationship is repeated sequentially, and the simultaneous color difference signal B-Y'' also has the color difference before the LH period.
-1 to ゛ - Color difference signal B-Yn-i before 2H period at that time (R-Yn++) and color difference -ra number B at the present time
-Y n+ Color difference with t divided by 2, -, (B
-Yn++) +(B Yn-+) 11111, ------ is a signal that is sequentially repeated from this 1JLj section.

However, the influence of changes in the color difference signals R-Y and B-Y is reduced by half, but the influence occurs over the 2H period.

Incidentally, in the case of fC using the circuit shown in FIG. 2, the luminance signal Y is also delayed by the IEI period, although not shown.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, it is an object of the present invention to provide a line-sequential video signal recording and reproducing system that can eliminate color errors on the reproduction side when a line-sequential system is adopted. The present invention that achieves this objective is @1 on the recording side.
While one color difference signal is delayed by an IH period before the button is pressed, the other color difference signal tone is delayed by an IH period on the reproduction side after synchronization, and the luminance signal is delayed by an IH period on either the recording side or the reproduction side. The basis of its technical philosophy is the fact that it made the mother-in-law a mother-in-law.

Embodiments of the present invention will be described in detail below with reference to all the drawings.

Figure 4 (L) is a block diagram showing a device that implements the recording method according to the embodiment of the present invention. As shown in the figure, the luminance signal Y of the video signal is input to the input terminal 1.
2, one of the video signals, the color difference signal R-Y, is input to the input terminal 1.
3, the other color difference signal B-Y of the video signal is input to input terminal 1.
A control pulse Pc whose state changes every IH is supplied to each of the control pulses 4 and 4. The luminance signal Y is subjected to FM conversion by an FM modulator 15 and is supplied to a carrier luminance signal and a mixer 16 . The color difference signals R-Y and B-Y are line-sequentialized by a line-sequentialization switch 17. That is, the line 11 @ secondary switch 17 is alternately connected to the contacts 17a and 17 every IH period by the control pulse Pc.
b Select either one of the color difference signals R-Y, B-Y.
select. Line sequential color difference signal R-Y obtained in this way
', B-Y' are 91M modulated by the FM modulator 17 to become a carrier color difference signal and supplied to the mixer 6; The recording head 20 is then connected to the recording head 20 via the recording amplifier 19.
The information is recorded on a magnetic recording medium (not shown). At this time, the color difference signal B-'Y is converted to IH prior to line sequentialization.
The period delay circuit 21 delays the plH period.

FIG. 4(b) shows the reproduction method according to the embodiment of the present invention.
FIG. As shown in FIG. head amp 32
Bypass filter 33 and low pass filter 3
4. ... In the pass filter 33, the signal is extracted from the carrier video signal J,
The demodulator 35 receives the result F
M saving go adjustment device 35's conversion Ij → [:° as Ruj1 degree news publication/Y. On the other hand, the low-pass filter 34 supplies the color difference signal output to the FM post-adjuster 36.

Line sequential color difference signals R-Y' and B-Y' are obtained as output signals of the Ii'M demodulator 36. One of the line sequential color difference signals R-Y' and B-Y' is demodulated before the IHM period and is supplied to the simultaneous switch 38 at the same time as the other signal delayed by the IH period delay circuit 37. The simultaneous switch 38 has the same configuration as the simultaneous switch 1 shown in FIG. That is, the synchronization switch 38 is a switch 39 that outputs the synchronized color difference signal R-Y'';
It has a switch 40 which outputs a simultaneous color difference signal B-Y''i.The switch 39 has a contact 39a.

39b'e, the switch 40 has contacts 40a and 40b, respectively, so that the contact 39a and the contact +ob, and the contact 39b and the contact 40a are selected simultaneously.
The switch 39 is directly operated by the control pulse Pc, and the switch 40 is inverted by the inverter 41 and switched every IH period.

Contacts 39a and 40a receive line sequential color difference signals R-Y', B-Y' delayed by the IH period, and contact 39b.
, 40b are supplied with the currently demodulated line-sequential color difference signals R-Y', B-Y', respectively. -Y
" is supplied to the mixer 43 via the balanced modulator 42, where it is combined with the luminance signal Y to form the original video signal, and this video signal is output via the output terminal 44. At this time, the synchronized color difference signal R-Y" is input to the IH period delay circuit 45 after synchronization until it reaches the balanced modulator 42, and the luminance signal Y is input to the mixer 43 after the synchronization. During this period, the IH period delay circuit 46 delays the respective signals.

5(a) to 5(il) are taken into account the temporal relationship with respect to the color difference signals R-Y and B-Y in the above-mentioned embodiment. FIG. 2 is an explanatory diagram conceptually showing the structure of a signal at each point.

In this case, the line sequential color difference signals R-Y' and B-Y' are as follows:
Regarding the color difference signal RLY, one belonging to an odd-numbered IH period is selected. In addition, Fig. 41-1(a) and Fig. 4 (
The 4-id structure of the signals at each point indicated by the symbols a-i in b) corresponds to one prefecture in FIG. 5 tal to FIG. 5 (i).

Figure 5 [bl, (e) and Figure 5 tg) * (b)
Yr: As you can see, color difference No. 1S R-Y
, , B-Y corresponding to the simultaneous color difference signals R-Y'', B-
Y” is 1 kI only for signals belonging to odd-numbered IH periods.
Although the period has been shifted, the combination of the two is the same (signals that belong to the same period. Therefore, the color difference signals R-Y, R-4" have changed significantly between the 111 period and the next LH period. In addition, since the luminance signal Y on the reproduction side is delayed by the IH period, no problem occurs in the even-numbered H periods between the luminance signal Y in the corresponding period and the color difference signal in the corresponding period. , and odd-numbered H
In the period, is it a combination with the luminance signal Y after the IH period?
This has a negligible effect on color. At this time, the luminance signal Y may be delayed by IH on the recording side.

As specifically explained above in conjunction with the embodiments, according to the present invention, the combination of color difference signals of two glazes on the reproduction side is only shifted downward during the IH period on the screen, and the combination of color difference signals is normal. Therefore, even if there is a large color change between one IH period and the next IH period, this effect will not appear on the student screen, and color errors due to this will not occur.
Can be removed.

[Brief explanation of the drawing]

Figure 1 (a) - Figure 1 (El Hani! Sequential method (Revised 11th diagram conceptually showing the structure of each color difference signal in C), Figure 2 is a reproduction to reduce color errors in the line sequential method. (1) j
Figures 3(a) to 3(d) show the temporal relationship of the simultaneous color difference signal to the color difference signal in the 2M conventional technology. FIG. 4(a) is a block diagram showing a device that realizes the recording method according to the embodiment of the present invention, and FIG. 4(b) is an explanatory diagram conceptually showing the structure of each. 5(a) to 5(il) are block diagrams showing an apparatus for realizing the endogenous method according to an embodiment of the present invention (il is a block diagram showing a device for realizing an endogenous method according to an embodiment of the present invention). It is an explanatory diagram conceptually showing the structure of the signal at each point in Fig. 4(a) and Fig. 4(b). .H delay circuit, 38 is a synchronization switch, R-Y, B-Y are color difference signals, R-Y', B-Y' are line sequential color difference signals, R-r, n
-y” is a simultaneous color difference signal. Patent applicant Fuji Photo Film Co., Ltd. agent Patent attorney Shibe Mitsuishi (and one other person)

Claims (3)

[Claims] (1) In a line-sequential video signal recording method in which two types of color difference signals are alternately selected every horizontal scanning period and recorded line-sequentially, one color-difference signal is delayed by one horizontal scanning period prior to line-sequentialization. A method for recording video signals in line sequential manner. (2) One color difference signal was delayed by one horizontal scanning period, selected alternately every horizontal scanning period, and recorded in line sequential form.
In a line-sequential video signal reproduction method in which all types of color difference signals are simultaneously reproduced, the line-sequential signals are delayed by one horizontal scanning period/(one color difference signal and the other color difference signal are selected in parallel) After synchronizing the color difference signals of Class 3 of the 2nd edition, the other color difference (i) is delayed by one horizontal scanning period.
Signal reproduction method. (3) lii: On the recording side, 1 type of Shikotan with 2 types of ID, 1
Horizontal scanning period 4fJ, VC alternately selected, too! On the other hand, on the playback side, line 116 shows the L-ordered signal delayed by 1 and 4 f j'Jj and the signal that is not delayed in line 31. Line 1 that synchronizes the color difference signals of the following [recording of video signals by
In the reproduction method, on the recording side, one color difference signal is delayed by one horizontal scanning period prior to line sequential A, while on the reproduction side, after synchronization, the other color difference signal is delayed by one horizontal scanning period, and then the entire luminance signal is recorded. A line-sequential video signal recording and angular production system characterized by delaying one horizontal scanning period by one side or the reproduction side.