JPH06326962A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To record a picture just before alarm input in the normal recording mode by rewinding a tape to restart recording one frame after the start point of the just preceding recording after recording a video signal continuously for a prescribed time and repeating this operation and performing the continuous recording operation after alarm detection. CONSTITUTION:For the purpose of performing long-time picture recording for monitor, a video control circuit 8 controls a video circuit 4 and a capstan control circuit 3 and normally runs a video tape to record the picture. Just before a prescribed time interval T, the tape is rewound at a high speed, and the tape is normally run again one frame after the start point of preceding recording to record the picture. When an alarm input signal is inputted from an alarm input terminal 5 to a circuit 2, recording in the recording mode of normal running is continued. The circuit is returned to the original operation again after a certain time (t) set by a normal recording signal 10 after the alarm input. By this operation, the picture just before the alarm input is recorded in the normal recording mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus for monitoring.

[0002]

2. Description of the Related Art In recent years, a recording / reproducing apparatus for surveillance (a VTR that performs a recording operation for recording frames and is referred to as a time-lapse VTR hereinafter) has been used as a surveillance security application in a financial institution, a late-night convenience store, etc. due to an increase in crime. (For example, Japanese Patent Laid-Open No. 61-23344)
No. 9).

FIG. 3 is a block diagram of a conventional time-lapse VTR. Reference numeral 1 is a time-lapse VTR, and its internal configuration will be described below.

Reference numeral 2 is a VTR control circuit, which is a VT at the time of abnormality.
This circuit controls the entire VTR including the R safety protection operation. A capstan control circuit 3 outputs a capstan drive signal 12 to a capstan motor 11 based on the capstan control signal 7 output from the VTR control circuit 2 to control the capstan motor. 4 is a video circuit, V
Recording and reproduction of a video signal are performed based on the video control signal 8 output from the TR control circuit 2. Reference numeral 5 denotes an alarm input terminal, which is connected to a door of a building or the like for detecting an abnormality, and the alarm input signal 6 is input to the VTR control circuit 2. A normal recording time setting switch 9 after alarm input outputs a normal recording time signal 10 after alarm input to the VTR control circuit 2.

In the conventional time-lapse VTR configured as described above, the video tape is intermittently run,
It is possible to record for a long time by recording the video signal at a predetermined time interval and record for a long time. When the alarm input signal 6 is input to the VTR control circuit 2, the frame recording by the intermittent running mode is not performed normally. Move to the recording mode of. Then, after a certain period of time set in the normal recording time signal 10 after the alarm is input, the mode shifts to the frame recording mode again.

[0006]

However, in the time-lapse VTR configured as described above, the important image immediately before the alarm is input is recorded in the normal recording mode for the frame recording by intermittent driving. Had the problem that not.

The present invention has been made in view of the above problems, and an object thereof is to provide a magnetic recording / reproducing apparatus capable of recording an image immediately before an alarm is input in a normal recording mode.

[0008]

In order to solve the above problems, according to the present invention, a magnetic tape transfer means for transferring a magnetic tape, a video signal recording means for recording a video signal on the magnetic tape, and the magnetic tape transfer. And a control means for controlling the means and the video signal recording means, and an alarm detection means for detecting an alarm input and supplying it to the control means.

[0009]

With the above means, the present invention repeats the operation of continuously recording the video signal for a predetermined time, rewinding the tape, and restarting recording one frame after the immediately preceding recording start position. After the alarm input is detected, the continuous recording operation enables continuous recording of the video immediately before the alarm input.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic recording / reproducing apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a magnetic recording / reproducing apparatus according to the present invention. In FIG. 1, reference numeral 1 is a time-lapse VTR, and the inside thereof will be described below. Reference numeral 2 is a VTR control circuit, which is a circuit for controlling the entire VTR including a VTR safety protection operation in the event of an abnormality. 3 is a capstan control circuit V
Capstan control signal 7 output from the TR control circuit 2
Based on the above, the capstan drive signal 12 is output to the capstan motor 11 to control the capstan motor. A video circuit 4 records and reproduces a video signal based on the video control signal 8 output from the VTR control circuit 2.
An alarm input terminal 5 is connected to a door of a building or the like for detecting an abnormality, and an alarm input signal 6 is input to the VTR control circuit 2. 9 is a normal recording time setting switch after alarm input, which is a normal recording time signal after alarm input 1
0 is output to the VTR control circuit 2.

The operation of the present embodiment configured as described above will be described below with reference to FIG.

FIG. 2 is a diagram showing the relationship between the tape running direction and time. The video tape is normally run and recorded, and immediately before the predetermined time interval T, the tape is rewound at high speed,
One frame after the previous recording start point, the video tape is normally run again for recording. By repeating this operation, it is possible to record a frame for a long time. When the alarm input signal 6 is input to the VTR control circuit 2 at the position A shown in the figure, the recording is continued in the normal running recording mode, After the alarm is input, the constant time t set in the normal recording time signal 10
After that, it returns to the previous operation again. By the above operation, the image just before the alarm input is recorded in the normal recording mode.

In the present embodiment, the normal recording time setting switch 9 after alarm input limits the normal recording time after alarm input, and thereafter returns to frame recording again to reduce extra tape consumption. However, the present invention is effective even for those without this function.

As described above, according to this embodiment, the image immediately before the alarm input can be recorded in the normal recording mode.

[0015]

As described above, according to the present invention, when there is an alarm input, the image immediately before the alarm input can be recorded in the normal recording mode, and the effect for monitoring use is great in time lapse. is there.

[Brief description of drawings]

FIG. 1 is a block diagram of a time-lapse VTR according to an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between tape running direction and time of a time-lapse VTR according to an embodiment of the present invention.

FIG. 3 is a block diagram of a conventional time-lapse VTR.

[Explanation of symbols]

 1 Time-lapse VTR 2 VTR control circuit 3 Capstan control circuit 4 Video circuit 5 Alarm input terminal 6 Alarm input signal 7 Capstan control signal 8 Video control signal 9 Normal recording time setting switch after alarm input Normal recording time signal after alarm input 11 Capstan motor 12 Capstan drive signal

Claims (2)

[Claims] 1. A magnetic tape transfer means for transferring a magnetic tape, a video signal recording means for recording a video signal on the magnetic tape, and a control means for controlling the magnetic tape transfer means and the video signal recording means. Alarm detection means for detecting an alarm input and supplying it to the control means, wherein the control means continuously records the video signal for a predetermined time on the magnetic tape transfer means and the video signal recording means. After that, the tape is rewound, and the operation of starting recording again one frame after the immediately preceding recording start position is controlled to be repeated, and after the alarm input is detected, continuous recording operation is performed. A magnetic recording / reproducing apparatus characterized by controlling. 2. A continuous recording time setting means for setting a continuous recording time to the control means, the control means after the alarm input is detected for the magnetic tape transfer means and the video signal recording means. A magnetic recording / reproducing apparatus which controls to perform a continuous recording operation according to the set continuous recording time.