JPS59117383A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To select and reproduce a prescribed video signal afterward by switching plural video signals coincident with an identical phase by each prescribed amount and synthesizing and recording one video signal to record plural video signals without synchronism. CONSTITUTION:When video signals S1, S2 not synchronized with each other are inputted from terminals 1, 2, they are synchronized at a phase adjusting circuit 3, a signal S4 synthesizing the signals S1 and S3 is obtained by the control of a switching circuit 4 and recorded by a recording head 10 through a recording circuit 9. A signal S5 the same as the signal S4 is obtained at a reproducing circuit 11 at reproduction, this signal S5 becomes a signal S6 with a prescribed delay at a delay circuit 12, the signals S5, S6 are switched sequentially by a switching circuit 13 and a reproduced output signal S7 is obtained. Further, a reproduced output signal S8 is obtained by inverting the switching timing.

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Application The present invention provides a magnetic recording and reproducing apparatus that can time-divisionally record a plurality of video signals at approximately the same time and later selectively reproduce these signals. Hereinafter referred to as VTR].

Conventional configuration and its problems In recent years, home VTRs have become widespread. but,
When recording television broadcasts, it was impossible to record and play back video signals from multiple channels at the same time with a single VTR. Furthermore, various methods are known for sequentially recording a plurality of video signals in a frame-by-frame manner.

For example, Japanese Patent Application Laid-Open No. 51-46821. However, these methods require a plurality of video signals to be in a synchronized relationship, and because information is recorded and reproduced intermittently, they have the disadvantage that the reproduced images are unnatural.

OBJECTS OF THE INVENTION The present invention provides a method for providing a plurality of B! l! An object of the present invention is to provide a VTR capable of recording all video signals and later selecting a predetermined video signal and reproducing it with high image quality.

Structure of the Invention The magnetic recording/reproducing apparatus of the present invention receives as input a plurality of video signals having synchronization signals that are unrelated to each other, and adjusts the phases of the vertical synchronization signals or horizontal synchronization signals of the video signals to the same phase using a phase adjustment circuit. The recording system is constructed so that the plurality of video signals that match the same phase are sequentially switched by a predetermined amount using a switching circuit to synthesize and record one composite video signal, and the reproduction system is constructed using a switching circuit. A plurality of unsynchronized video signals are recorded by selecting and reproducing only a predetermined time, and outputting a signal replaced with information obtained from the reproduced signal during the unselected time. It is characterized by being able to reproduce video signals).

Further, the magnetic recording/reproducing device of the present invention receives as input n (n to 1) video signals having synchronization signals that are unrelated to each other, and adjusts the phase of the vertical synchronization signal or the horizontal synchronization signal of the video signals. The n video signals that match the same phase are made to have the same phase by a circuit, and the time axis of each of the n video signals that match the same phase is compressed to 1/n by a predetermined section time axis conversion circuit, and the compressed signals are sequentially switched and synthesized by a switching circuit. The recording system is configured to record one composite video signal, and the reproduction system is configured to expand a predetermined section by n times and reproduce it.
This makes it possible to record a plurality of unsynchronized video signals and reproduce a predetermined video signal without degrading the image quality.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on FIGS. 1 to 6.

FIG. 1 shows a block diagram of an embodiment of the present invention. Ill +2) are input terminals, (3) are phase adjustment circuits, (4) α1 are switching circuits, +5)
[12 are delay circuits, (6) are control circuits, (7
) +8) (14) (c) are switches, (9
] is a recording circuit, 00 is a magnetic field, '\rad θυ is a reproduction circuit, ([6 is a sword terminal. Note that the recording circuit (9), reproduction circuit αη, and magnetic head Ql) are directly related to the present invention. There isn't.

FIG. 2 shows the main part waveform diagram of FIG. 1 and other waveform diagrams, and shows signals S1 to S7. B8 is the first
S1 to S7 of the figure. The waveform at B8 is shown.

A1 to AIO each represent the video signal A divided into predetermined sections. B1 to B are each video signal B
is divided into predetermined intervals.

Here, the predetermined section may be n fields or n horizontal scanning periods (hereinafter referred to as H) (however, n is a natural number). For example, if it is one field unit, A7. A2
. . . each indicates one field, and the dividing pulse P indicates a vertical synchronizing signal. Also, as another example, if there is an IH small unit, AI
+A2... each indicates an IH section, and in this case, pulse Pl indicates a horizontal synchronizing signal.

Signal S1 input to input terminal +1) and input terminal (2)
As shown in FIG. 2, the synchronization with the signal S2 input to the signal S2 is out of synchronization. If recording and reproducing are performed in this state, switching noise will occur in the center of the screen, resulting in an unsightly image, so synchronization is achieved using the phase m alignment path (3). In FIG. 1, the phase adjustment circuit (3) is composed of a delay circuit (5) and a control circuit (6) including a phase comparator. Here, the phase adjustment circuit (3
) adjusted B1 r B2... through bl, b
2... In this way, the synchronized signals A1 to A
IO and b1 to b are combined to obtain a 7-synthesized signal S4, which is passed through the recording circuit (9), but in the reproduction system, it is necessary to temporally separate the two video signals. Therefore, the delay circuit board causes the signal S5 to
is delayed by a predetermined amount to obtain the signal S6, and the switching circuit C1''4 sequentially switches the signals S5 and 86 to obtain the reproduced output signal S7. Furthermore, by setting the switching timing to the opposite phase, the reproduced output signal S8 is obtained. For example, if the predetermined interval is for each field, a field skip image will be obtained, and if the predetermined interval is for each IH, a full field image will be obtained (however, the vertical resolution will be halved).However, the phase adjustment circuit ( 3) Since the synchronization is achieved, whether it is the A image or the 8 image, the switching timing can be performed in the vertical retrace interval or the horizontal retrace interval, and it is possible to obtain a beautiful image that does not generate switching noise on the screen. I can do it.

Here, since the same signal is reproduced for two consecutive sections, an unnatural image will appear on a screen with little field correlation or line correlation (for example, a screen with rapid movement). Therefore, by replacing the unreproduced interval with the average value of the signals reproduced before and after the interval, the image becomes smoother and easier to view.

FIG. 8 shows this embodiment. The difference from FIG. 1 is that the number of delay circuits and adders is increased. The delay time of delay circuit 0 is set to twice that of delay circuit (2). Therefore, the output signal S of the delay circuit □Samurai is the signal S5
is delayed by two sections. This signal S and 85 are added by an adder. In this example, this addition is performed at the video signal level, but other examples may be used. For example, it is possible to convert it into a digital signal and perform gauge threat processing. The signals S, o obtained in this way and the signal S6 delayed by the delay circuit (6) are connected to the switch α (
By switching in accordance with the signal from the switching circuit (g) in g), the reproduction output S11 or S12 shown in FIG. 2 can be obtained. It can be seen that this allows a smooth reproduced image to be obtained.

FIG. 4 shows a block diagram of a recording system according to another embodiment of the present invention, in which input terminals (M), (C), and (C) are respectively input terminals, (C) and (C) are delay circuits, and (E) and (I) are respectively input terminals. ) is the control circuit, (c)
翰(7) is a time axis conversion circuit, 01) is a switching circuit, ni)(
To) (C) indicates a switch, and (To) indicates a mixer. +9) (111 is a recording circuit and a magnetic head. The delay circuit (c) and control circuit (e) form a phase adjustment circuit (to).
is formed. Similarly, the delay circuit (delay circuit) and control circuit (a) also form a phase adjustment circuit (b).

The video signal whose time axis has been compressed by the time axis conversion circuit (c) 01 (1) passes through the switch (a) C33■ controlled by the switching circuit e, and is mixed in the mixer (2). , and are recorded through the X recording circuit (9). Figure 5 (a
) (b) shows an example of a reproducing system for a magnetic tape recorded with the recording system shown in Figure 4, and (to) ■)
is the time axis conversion circuit, @I) @6 is the switching circuit, (6)a
tomno indicates a monitor television. Figure 5(a) shows the number of n (for example, n=3) recorded in Figure 4.
) is a configuration diagram when three separate video signals are simultaneously played back on n monitors (e.g. 8 monitors), Figure 5%
(b) shows a configuration diagram when only a desired video signal is reproduced on one monitor.

FIG. 6 shows waveform diagrams of the main parts of the embodiment shown in FIG. 4 and FIGS. 5(a) and 5(b), and P1 to PIO correspond to P1 to PIO in FIGS. 4 and 5, respectively. are doing. Referring again to FIG. 6, the operations in FIGS. 4 and 5 will be explained next.

First, the unsynchronized video signal input from the input terminal (2) @(A) is synchronized by the phase adjustment circuit clIS@ and becomes Pl, P2, Ps, and then the time axis conversion circuit ( C) Time axis is compressed by Kankan and P4 r
It becomes P5 * P6.

By appropriately switching and mixing these signals in the switching circuit 6υ, a signal P7 is obtained at the output of the mixer (to), which is recorded through the recording circuit (9). During reproduction, if there are a plurality of reproduction monitors, the configuration will be as shown in FIG. 5(a), and if there is one, the configuration will be as shown in FIG. 5(b). The reproduced signal P7 is time-axis expanded by the time axis conversion circuit 08 (a) c4c) or 2), converted into a signal as shown in P8 r P9 r Plo, and then displayed on each monitor (a)) or (B)
sent to. In this case, FIG. 6 P8. P9, P.I.
As shown in O, there is no dropout of the video signal, and the same beautiful image as when the signal was input is reproduced.

It is clear that only any desired signal can be reproduced by commands shown in FIG. 5(b) to the switching circuit.

Here, A,,A2. As described in the above embodiment, the divisions such as A3... etc. are in units of one field, but the
It may be in units of H.

The phase adjustment circuit in each of the above embodiments is composed of a delay circuit and a control circuit including a phase comparator as described above, and is configured to control the vertical synchronization signal or the horizontal The control circuit is configured to compare the periodic signal with the phase of a vertical synchronization signal or a horizontal synchronization signal of the output video signal of the phase adjustment circuit, and control the delay circuit with the control circuit so that the phases of both signals match. There is.

The delay circuit in each of the above embodiments is an analog delay element such as a CCD, or an A/D or D/A conversion element.
It can also be configured with a circuit that includes a memory and processes in a digital system. When processing in a digital system, the input video signal is converted into a digital signal, written into a memory, read out in response to a read command from a control circuit, and then converted into an analog signal and output. Also,
As shown in the above-described embodiment, when outputting the average value of two signals, it is considered easier to process if the calculation is performed in a digital system. 1. Effects of the Invention As is clear from the above explanation, according to the magnetic recording and reproducing apparatus of the present invention, a plurality of video signals having mutually unrelated synchronization signals are input, Alternatively, the phase of the horizontal synchronization signal is made to match the same phase by a phase adjustment circuit, and a plurality of video signals that match the same phase are sequentially switched in predetermined amounts at a time to synthesize and record one composite image signal, and at the same time, the playback system is , the switching circuit selects and reproduces only a predetermined period of time, and outputs a signal replaced with information obtained from the reproduced signal during the unselected time, so multiple channels at the same time but not synchronized with each other are output. This provides the advantage that a video signal can be recorded and played back on a single VTR.

Further, the magnetic recording/reproducing device of the present invention receives n video signals (where n = 1) having synchronization signals that are unrelated to each other as input, and adjusts the phase of the vertical synchronization signal or the genuine leather synchronization signal of the video signals. The n video signals that matched the same phase were made to match the same phase by an adjustment circuit, and the time axis was compressed to 1/n for each predetermined section, and the compressed signals were sequentially switched and synthesized to form one composite signal. Since the playback system expands the predetermined section by n times and plays it back, multiple unsynchronized signals can be recorded and played back without degrading the information, and the video signals of multiple channels at the same time can be played back. 1
It can be recorded and played back on a single VTR, and has the great effect of playing back beautiful images.

Further, according to the present invention, it can be used as a monitoring VTR that requires checking a plurality of locations at the same time, and has great effects.

[Brief explanation of drawings]

1 and 3 are block diagrams of one embodiment of the magnetic recording/reproducing apparatus of the present invention, FIG. 2 is a waveform diagram of the main parts in FIGS. 1 and 8, and FIG. 4 is a diagram of another embodiment of the magnetic recording/reproducing apparatus of the present invention ￥The configuration diagram of the recording system of the example, FIG. It is a waveform diagram of the main part of the figure. +t) (2) all wires (2)...input terminal, (5
) (2) Osu (c) (c)...Delay circuit. (6) (c) (b)...control circuit, (4) (to) 6η
to θυ)...switching circuit, (9)...recording circuit, aυ
... Regeneration circuit, (C) Kan (E) (To) Kan 11... Time axis conversion circuit agent Yoshihiro Morimoto No. 5 (Sn (k)

Claims (1)

[Claims] 1. A plurality of video signals having synchronization signals that are unrelated to each other are manually adjusted so that the phases of vertical synchronization signals or horizontal synchronization signals of the video signals are made to match the same phase by a phase adjustment circuit, and the same phase The recording system is configured to sequentially switch a plurality of reflection signals that match the above, one by one using a switching circuit to synthesize and record one composite video signal, and the reproducing system is selected only for a predetermined period of time using a switching circuit. A magnetic recording/reproducing device configured to output a signal replaced with information obtained from the reproduced signal at a time when the reproduced signal is not selected. 2. Claims characterized in that the composite video signal is configured such that a plurality of video signals are sequentially switched and composited every n fields or every n horizontal periods (where n is a natural number) by a switching circuit. 2. The magnetic recording and reproducing device according to item 1. 8. The reproduction system is configured to select and reproduce only a predetermined time, and output a delayed signal of the reproduction signal during the time when iJ is not selected. The magnetic recording and reproducing device described above. 4. The reproduction system repeats the reproducing operation and non-reproducing operation every predetermined interval, which is one horizontal synchronizing signal interval or one vertical synchronizing signal interval.
and 2 horizontal synchronization signal sections before the predetermined section or 2
A signal reproduced in a predetermined section before the vertical synchronization signal section
0, and this signal Ao is divided into 2 horizontal synchronizing signal sections or 2
If the signal delayed in the vertical synchronization signal section is AO/, then in the section where the signal An is reproduced, the signal An and the signal Ao' are mixed and obtained as An+Ao.
5. The magnetic recording and reproducing apparatus according to claim 1, wherein the magnetic recording and reproducing apparatus is configured to output the signal -Tm which is the same as that of the magnetic recording medium, and to output the signal "An" in a section that is not reproduced immediately after the section. , the phase adjustment circuit is composed of a delay circuit and a control circuit including a phase comparator, and is configured to synchronize the vertical synchronization signal or horizontal synchronization signal of a predetermined one of the plurality of input video signals with the phase adjustment circuit. Claim 1, characterized in that the delay circuit is controlled by the control circuit so that the phase of the vertical synchronization signal or the horizontal synchronization signal of the output video signal is compared so that the phases of both signals match. The magnetic recording/reproducing device according to item 1. 6. The delay circuit is composed of an A/D converter, a D/A converter, and a memory, converts the input video signal into a digital signal, writes it into the memory, and outputs the digital signal from the control circuit. The magnetic recording and reproducing device according to claim 5, characterized in that the magnetic recording and reproducing device is configured to convert the signal into an analog signal and output the signal after being read in response to a read command. 7. Having synchronization signals that are not related to each other. n pieces (however,
n to 1) video signals are input, the phases of the vertical synchronization signals or horizontal synchronization signals of the video signals are matched to the same phase by a phase adjustment circuit, and the n video signals that match the same phases are plotted on the time axis for a predetermined period. The recording system is configured to compress the time axis to 1/n in a conversion circuit, and record one composite video signal by sequentially switching and synthesizing the compressed signals in a switching circuit. A magnetic recording and reproducing device configured to expand and reproduce n times. 8. The magnetic recording and reproducing apparatus according to claim 7, wherein the predetermined period is n field period or n horizontal scanning period.