JPH05219474A - Video tape recorder - Google Patents

Abstract

PURPOSE:To record/reproduce plural kinds of signals by mixing a 1st input signal and a 2nd input signal while being synchronized with each other on one scanning line and recording the mixed signal. CONSTITUTION:A 1st input signal A or a 2nd input signal B is switched by a changeover control section 5 through a selector 2 in the unit of one picture element. An A/D converter converts analog data into digital data, the data are stored in a memory 4 and when the conversion by one scanning line is finished, the data are recorded on a magnetic tape through a recording amplifier 6. The data read from the magnetic tape through a reproduction amplifier 7 are stored in the memory 4. The data designated in advance are sequentially read by the changeover control section 5 and a D/A converter 8 converts the digital data into analog data, and the data pass through an output signal processing section 9, then the selected pattern is outputted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video tape recorder, and more particularly to a mechanism for simultaneously recording a plurality of channels and reproducing them independently.

[0002]

2. Description of the Related Art Generally, a conventional video tape recorder has one channel (A) as shown in FIGS.
Signal is input from the input signal processing unit 1, and the signal is recorded on the magnetic tape by the recording amplifier 6. During reproduction, the signal read by the reproduction amplifier 7 is output to the output signal processing unit 9
It was projected on TV through.

Although there is an EP mode in VHS video as a method of increasing the recording time although the image quality deteriorates, the channels of different time can be recorded for a long time, but the recording of a plurality of channels cannot be performed at the same time. In order to record a plurality of channels at the same time, it was necessary to use an expensive magnetic head to expand the recording band, prepare magnetic media separately, and record.

[0004]

In the conventional video tape recorder, a plurality of video tape recorders, a special video tape recorder capable of wide band recording, and the like are prepared in order to record and reproduce a plurality of channels at the same time. It has the disadvantage that it is necessary and expensive.

It is an object of the present invention to provide a video tape recorder which eliminates the above drawbacks and can record and reproduce a plurality of channels at low cost.

[0006]

The structure of the video tape recorder according to the present invention is such that the video input from a plurality of channels
It is characterized by including a function of switching the audio signal in a time division manner and a means for independently reproducing the signals of a plurality of channels for each channel.

[0007]

1 and 2 are block diagrams of a recording unit and a reproducing unit, respectively, showing a video tape recorder according to a first embodiment of the present invention.

1 and 2, the video tape recorder of the present invention includes input signal processing units 1a and 1b to which channels A and B are input, a selector 2 and a recording amplifier 6, respectively.
And a recording unit having a switching control unit 5.
Further, it is provided with a switching control recording unit 5, a reproduction amplifier 7, a multiplexer 11, and output signal processing units 9a and 9b.

Next, the basic operation of this video tape recorder will be described with reference to FIGS.

The ratio of the time division of the two channels A and B will be explained as 1: 1. In FIG.
Input signal processing unit 1 for signals from two channels A and B, respectively
Input to a and 1b. Next, the switching control unit 5 alternately switches the inputs of the input signal processing units 1a and 1b for each pixel unit obtained from the frequency band of the signals of channels A and B, and the output signal from the selector 2 is the recording amplifier 6 Is recorded on a magnetic tape.

Next, when reproducing the recorded magnetic tape, referring to FIG. 2, let us say that the data of the recorded magnetic tape is passed through the reproduction amplifier 7 and the image of channel A is outputted here. The part 5 is the multiplexer 11
The channel A signal is sequentially input to the output signal processing unit 9a, and the channel A is output.

In this way, the amount of information is halved compared to the conventional one, and the image quality is deteriorated, but it is possible to record / reproduce a plurality of channels simultaneously.

FIGS. 3 and 4 are block diagrams of a recording unit and a reproducing unit, respectively, showing a video tape recorder according to a second embodiment of the present invention.

In FIGS. 3 and 4, this embodiment is a D / A
Converters 8a and 8b and signal complementation processing units 10a and 10
b is different from the multiplexer 11 in FIG. 2 in that it is provided with a memory 4 and the other parts are the same as those in the first embodiment.

Here, the second embodiment performs time division similarly to the first embodiment in which two channels are simultaneously recorded,
In the N field, the odd numbered data of channel A
The switching control unit 5 switches the channel B to output even-numbered data, the channel A to output even-numbered data, and the channel B to output odd-numbered data in the N + 1 field. The output data is the recording amplifier 6
Is recorded on the magnetic tape through.

Next, when reproducing the recorded magnetic tape, as shown in FIG. 4, the data read through the reproducing amplifier 7 is stored in the memory 4, and it is considered that the channel A is output here. Then, the odd-numbered data in the N field is left as it is by the signal complementation processing unit 10 and the even-numbered data in which the data is lost is not compensated by the even-numbered data recorded in the N-1 field.
The data passes through the A converter unit 8a, and the D / A converter unit 8a converts the digital data into the analog data, passes through the output signal processing unit 9a, and the A channel A
Is output as a signal.

In this way, it is possible to record and reproduce a plurality of channels at the same time while obtaining an image quality close to that of a conventional room for recording one channel.

As a third embodiment of the present invention, FIGS.
If channel A and channel B are recorded at a ratio of 9: 1 in the block diagram, channel A can be recorded / played as a screen with almost no deterioration in image quality and channel B as a still image or a screen with little motion. Usage method is possible.

[0019]

As described above, according to the present invention, the input signal processing unit for processing the input video / audio signals of a plurality of channels and the control signal for switching these signals for each pixel are output. A switching control unit, a selector that switches according to the control signal, a recording unit including a recording amplifier that records the data, a reproduction amplifier that reads out the recorded magnetic tape, and one channel of the reproduced data are selected. When the output signal processing unit for outputting is provided, there is an effect that one inexpensive apparatus can record a plurality of channels at the same time.

[Brief description of drawings]

FIG. 1 is a block diagram showing a recording unit of a video tape recorder according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a reproducing unit of the video tape recorder shown in FIG.

FIG. 3 is a block diagram showing a recording unit of a video tape recorder according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a reproducing unit of the video tape recorder shown in FIG.

FIG. 5 is a block diagram showing a recording unit of a conventional video tape recorder.

6 is a block diagram showing a reproducing unit of the video tape recorder of FIG.

[Explanation of symbols]

 1a, 1b Input signal processing unit 2 Selector unit 3 A / D converter unit 4 Storage device 5 Switching control unit 6 Recording amplifier 7 Reproducing amplifier 8a, 8b D / A converter 9a, 9b Output signal processing unit 10a, 10b Signal complementation processing unit 11 multiplexer

Claims (1)

[Claims] 1. A recording apparatus having a function of switching video / audio signals input from a plurality of channels in time division for each pixel, and recording means for recording the signals switched by the function on a magnetic tape, A video tape recorder, comprising: a reproducing device having means for independently reproducing the magnetic tape recorded in the device for each channel.