KR100433198B1 - The recording method of time lapse vcr - Google Patents

Abstract

The present invention provides a recording method of a time-lapse VCR in which an overlapping section does not occur by synchronizing REC-H to a rising edge of a video head switching signal to perform recording-pause-recording. Determining whether the recording mode is a time lapse recording mode; if the determination result is a time lapse recording mode, generating a switching pulse for controlling a recording head; and using the switching pulse, output the REC-H signal to the recording head. The step of starting recording in synchronization with the rising edge of the switching pulse applied to prevents overlapping recording sections during continuous recording so that a clearer picture can be viewed.

Description

Time Lapse V-Cal recording method {THE RECORDING METHOD OF TIME LAPSE VCR}

TECHNICAL FIELD The present invention relates to BC-R (hereinafter referred to as "VCR"), and more particularly to Time Lapse VCR.

In general, Time Lapse VCRs can record for up to 24 hours and are used for security purposes with surveillance cameras.

1 illustrates a servo unit of a general time-lapse VCR.

A general time-lapse VCR will be described with reference to FIG. 1.

As shown in FIG. 1, the software servo 1 uses a software method such as a head switching signal (H'D S / W), a recording stop (REC MUTE), a F _H correction, a drum / capstan motor control voltage. And a recording control pulse (RECP-CTL).

The video signal processing section 2 processes the video signal to be recorded or reproduced, and the drum and video head 3 record or reproduce the video signal by rotating the same edgemuser 4 head 4 H'D at an appropriate speed.

The capstan motor 4 drives the video tape at a fixed speed, and the control head 5 records or reproduces a signal of an appropriate period suitable for the time-lapse system.

In order to record 12H / 24H time-lapse by the configuration of the servo unit shown in FIG. 1, the capstan motor 4 is slowly rotated at / 7 times speed for 12H and / 13 times speed for 24H. At this time, the reference speed is set to SP.

The drum 3 rotates at a speed of 1800 rpm as in the VHS format, so that superposition recording occurs.

To prevent this, a recording stop signal is supplied to the video signal processing unit 2.

When the superposition recording is canceled, the supply of the recording stop signal to the video signal processing section 2 is stopped and the next field is recorded by the field sampling method.

In the 12H / 24H playback mode or the multi-function mode such as still and search, recording and playback operations are performed using the same azimuth, thereby preventing noise from edgemus damage.

However, since such time-lapse VCRs are not compatible with the general VHS and use the same edge mushead, normal magnetic tapes cannot be reproduced due to the loss of muscle, and magnetic tapes recorded by the time-lapse VCRs cannot be reproduced by the normal VCRs.

In order to solve this problem, a time-lapse VCR according to the prior art has been proposed.

2 is a block diagram showing a servo unit used in a time-lapse VCR according to the prior art.

As shown in FIG. 2, the configuration is analog servo 20, video signal processor 21, F _H corrector 22, drum and video head 23, gain adjuster 24, capstan motor 25. And the control head 26.

Referring to the operation according to such a configuration, first, the analog servo 20 generates a REC MUTE signal and a recording control pulse suitable for a time-lapse operation, and appropriately selects the double azimuth four heads accordingly. A head switching signal (H'D S / W) and a rotary switching pulse (ROT, S / W) are generated to read a video signal. In addition, a control voltage is supplied to the capstan motor 25, and the phase of the capstan motor 25 is controlled by reading the control pulse recorded in the control head 26.

The video signal processing unit 21 processes the video signal to be recorded or reproduced, and the F _H compensator 22 detects that a skew occurs when the head _H is misaligned when the 12H / 24H is recorded. In order to prevent this, it is corrected by synchronizing F _H with the REC MUTE signal.

The drum and video head 23 uses double azimuth four heads so that the head with the same recording pattern and azimuth can always read the signal.

The gain adjuster 24 adjusts the control gain of the capstan motor 25 according to the rotational speed of the motor, and the capstan motor 25 rotates with appropriate gain control from the low speed of 12H / 24H to the search speed.

The control head 26 records or plays back control pulses of appropriate periods for the time-lapse VCR.

In order to enable recording of about 12 hours or 24 hours based on the T-120 paper in the conventional Time Lapse VCR, the capstan motor 25 is first operated in SP mode so that the tape can continuously run for 12H / 24H. / 7x) or 13x (24H).

While the tape travels at extremely low speeds, the drum spins at the same speed as the VHS format at 1800 rpm, causing severe overlap between the intracks.

To solve this problem, a field sampling method is adopted in which the recording is stopped at the time when the tape is moved to the section where the superimposed recording does not occur, and the video signal is recorded when the head is driven at a predetermined timing after the superimposition disappears.

However, even when sampling, sampling must be an odd multiple, such as / 7, / 13, etc. in order to keep the principle of composing one frame by performing recording or reproducing operation alternately between CH1 and CH2 heads.

FIG. 3 shows the switching logic of the video head. The video head switching logic according to the recording or playback speed in the recording (REC) and playback (PB) modes, STILL, SLOW, and SEARCH is shown. Video logic in a multifunction mode such as (SEARCH) is shown.

However, since the conventional time-lapse VCR is controlled by using the REC-H signal in performing the recording (REC) -pause (PAUSE) -recording (REC), overlap of the recording section occurs.

In sampling to remove the overlap section, sampling must be odd, such as / 7, / 13, etc. in order to keep the principle of composing a frame by performing recording or reproducing operation alternately between CH1 and CH2 heads. There is a restriction to be doubled.

Disclosure of Invention The present invention has been made to solve the above-described problems, and a time-lapse VCR in which an overlap section is not generated by performing recording-pause-recording by synchronizing a REC-H to a rising edge of a video head switching signal is performed. Its purpose is to provide a method of recording.

1 is a configuration diagram of a servo unit of a general time-lapse VCR

2 is a block diagram of a servo unit used in a time-lapse VCR according to the related art.

3 illustrates switching logic of the video head.

4 is a schematic diagram illustrating a time-lapse VCR of the present invention.

5 is a flowchart for explaining a recording method of a time-lapse VCR of the present invention.

♣ Explanation of symbols for main part of drawing ♣

41: recording head 42: switching pulse generator

43: inverter 44: REC-H output timing determiner

45: video signal processing unit 46: control unit

In the recording method of the time-lapse VCR according to the present invention for achieving the above object, in the recording method of the time-lapse V-Cal, the step of determining whether the recording mode is the time-lapse recording mode if the recording mode, the determination; As a result, in the time-lapse recording mode, generating a switching pulse for controlling the recording head, and starting recording by synchronizing the REC-H signal with the rising edge of the switching pulse applied to the recording head using the switching pulse. A step is made.

Hereinafter, a recording method of a time-lapse VCR of the present invention will be described with reference to the accompanying drawings.

First, the present invention does not determine the start of recording as the REC-H signal, but sets the rising edge timing of the switching pulse that determines on / off of the recording head to the starting point of recording so that the REC-H signal is actually rising of the switching pulse. Recording is performed at the point of synchronization with the edge.

4 is a schematic diagram illustrating a recording method of a time-lapse VCR according to the present invention.

As shown in FIG. 4, the recording head 41, the switching pulse output part 42 which outputs the switching pulse for controlling ON / OFF of the recording head 41, and the said switching pulse output part 42 The output timing of the REC-H using the inverting unit 43 for inverting the switching pulse output from the switching unit, the switching pulse output from the switching pulse output unit 42, and the switching pulse inverted by the inverting unit 43. And a REC-H output timing determiner 44 for outputting a REC-H signal to the recording head 41, a video signal processor 45 for transmitting a video signal to the recording head 41, and And a controller 46 for controlling the system.

The operation according to the above configuration is as follows.

If the user selects the PAUSE key during recording, the switching pulse generator 42 outputs a switching pulse for stopping the recording head 41 to prevent the recording head 41 from operating anymore. .

After that, when the recording key is selected again, in order to prevent the recording key from overlapping with the previous recording section, in the present invention, the REC-H signal is accurately synchronized to the rising edge of the switching pulse controlling the recording head.

To this end, in the present invention, after inverting the switching pulse in the inverting unit 43, the pulses before the inversion and the inverted pulses are gated by the NMOS transistor and the PMOS transistor of the REC-H output timing determining unit 44. The output timing of the REC-H is adjusted so that the REC-H signal is applied at the rising edge of the switching pulse.

This will be described with reference to the flow chart shown in Figure 5 the recording method of the time-lapse VCR of the present invention.

First, it is determined whether the current mode is the recording mode or the playback mode (S501). If the recording mode, the time-lapse recording mode is checked (S502). If the recording mode is not, the standby state is maintained (S503).

When the time-lapse recording mode is checked, if the time-lapse recording mode is checked, the controller checks whether the REC-H signal is detected (S504). If the REC-H signal is detected, the controller determines whether the switching pulse is detected (S505).

When the switching pulse is detected, recording is performed (S506).

Here, since the REC-H signal is not applied to the recording head until the switching pulse is detected, the recording is not actually performed.

Since the switching pulse and the inverted switching pulse must be applied to the NMOS transistor and the PMOS transistor of the REC-H output timing, the REC-H signal is not transmitted to the recording head until the switching pulse is generated.

Recording is performed through the above process, and after checking whether the recording end signal is input (S507), when the recording end signal is input, the recording is stopped.

As described above, the recording method of the time-lapse VCR of the present invention prevents the recording section from overlapping by synchronizing REC-H to the rising edge of the switching pulse controlling the recording head in order to prevent the recording section from overlapping during continuous recording. Can be.

Claims (1)

In the recording method of time-lapse V-seal, Checking whether the recording mode is a recording mode and determining whether the recording mode is a time lapse recording mode; Generating a switching pulse for controlling the recording head in the time lapse recording mode as a result of the determination; Inverting the generated pulse and determining whether the switching pulse and the inverted switching pulse are input; And outputting a recording start control signal only when the switching pulse and the inverted switching pulse are input.