JPH1198457A - Video recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record a stored video image before an alarm signal is received with high density by varying a prescribed interval at which a video signal stored in a storage memory is extracted and fed to a recording means. SOLUTION: An input circuit 111 extracts a video signal from a camera at a 1st interval and gives it to a memory circuit 112 and an output circuit 123. The memory circuit 112 stores the received and extracted video signal at a 2nd interval that is slightly longer than the 1st interval. An output control circuit 113 under the control of an input control circuit 114 provides an output of the video signal at the 1st interval, the video signal stored at the 2nd interval video signal that is the stored video signal and thinned at a 3rd interval to a video recording section 120. Upon the receipt of an alarm signal from a control terminal Tcont , the input control circuit 114 allows the video recording section 120 to record at the 2nd interval the stored video image having been recorded at the 3rd interval and to record a monitor video image at the 1st interval when the storage of the video recording is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video recording apparatus, and more particularly, to a video recording apparatus that records video signals intermittently.

[0002]

2. Description of the Related Art Surveillance cameras are installed in banks, stores, and garages for security purposes. Normally, images captured by the monitoring camera are recorded on a VTR and can be reproduced as needed. For a VTR for recording a video captured by such a monitoring camera, 24-hour monitoring is required. However, at present, a VHS system VTR can record only up to about 9 hours.
It is necessary to switch R and exchange the tape cassette,
Operability is not good.

In such a VTR, there is no need to record a moving image when there is no security problem, that is, when there is no person or the like and there is no movement on the screen. Therefore, as a VTR for recording a video for monitoring, a so-called time-lapse VTR is widely used, in which a video signal to be recorded on the tape cassette is fragmented to greatly increase a recording time on the tape cassette. Have been.

In a time-lapse VTR, when performing intermittent recording, first, a drum is rotated and a magnetic tape is run. Next, when the rotation of the drum and the running of the magnetic tape are stabilized, an image captured by the monitoring camera at that time is recorded on the magnetic tape. When the recording of the video is completed, the running of the magnetic tape is stopped, the tape is rewound slightly, the tension of the magnetic tape is reduced, and then the rotation of the drum is stopped. In the time lapse VTR, the above operation is repeatedly performed to perform intermittent recording.

In a time-lapse VTR, rotation of a drum,
Since the stop, running, stopping, and rewinding of the magnetic tape must be repeated every intermittent period, the magnetic head, the magnetic tape, and the running system thereof are severely worn. In order to solve this problem, for example, an intermittent recording apparatus as disclosed in JP-A-6-261284 or JP-A-60-2100 has been proposed.
No. 88 has proposed a visitor recording device.

In the intermittent recording apparatus disclosed in Japanese Patent Application Laid-Open No. 6-261284, a memory for storing video signals for a plurality of screens is provided at a stage preceding the VTR, and the video signals are intermittently temporarily recorded in the memory. After the video signals for a plurality of screens are stored in the memory, the video signals for a plurality of screens held intermittently are supplied to a VTR and recorded on a magnetic tape. FIG. 4 shows a block diagram of a conventional example.

[0007] An input video signal is supplied to the video signal input terminal Tin from a monitoring camera or the like. The input video signal supplied to the video signal input terminal Tin is supplied to the memory circuit 1. The memory circuit 1 intermittently stores input video signals supplied to the video signal input terminal Tin for a plurality of screens. The memory circuit 1 is connected to the modulation circuit 2, and supplies the video signals for a plurality of screens to the modulation circuit 2 when the input video signals are accumulated for a plurality of screens.

[0008] The modulation circuit 2 modulates the video signals for a plurality of screens supplied from the memory circuit 1 so as to be recorded on the magnetic tape 5. The video signal modulated by the modulation circuit 2 is supplied to the recording amplifier 3. The recording amplifier 3 amplifies the video signal modulated by the modulation circuit 2 and supplies the amplified video signal to the magnetic head 4. The magnetic head 4 is fixed to a head drum. The head drum is rotated by a drum motor. The magnetic head 4 rotates with the rotation of the head drum, and scans the magnetic tape 5. At this time, the magnetic tape 5 is run at a constant speed by the capstan motor.

A drum motor for rotating the head drum is connected to a head drum drive circuit 7. The head drum drive circuit 7 drives the drum motor according to a command supplied from the control circuit 8. The capstan motor for running the magnetic tape is connected to the capstan drive circuit 6. The capstan drive circuit 6 drives the capstan motor according to a command supplied from the control circuit 8.

The control circuit 8 is connected to the memory circuit 1, the head drum drive circuit 7, and the capstan drive circuit 6, and controls the video signal to be recorded intermittently on the magnetic tape 5. FIG. 5 shows a flowchart of a conventional control circuit. The control circuit 8 controls the memory circuit 1 so as to capture and store a video signal every n screens from the video signal supplied from the input terminal Tin (Step S1-1).

When the video signal for m screens is stored in the memory circuit 1 (step S1-2), the control circuit 8 instructs the head drum driving circuit 7 to rotate the head drum at a predetermined rotation speed. Is transmitted to the capstan driving circuit 6 so that the magnetic tape 5 runs at a predetermined speed (step S1-3). Next, the control circuit 8
When the rotation of the head drum and the running of the magnetic tape are stabilized, the video signal stored in the memory
(Step S1-4). When all of the video signals stored in the memory circuit 1 are output to the modulation circuit 2 and recorded on the magnetic tape 5, the control circuit 8 issues a command to the head drum driving circuit 7 to stop the head drum. Along with the transmission, a command is transmitted to the capstan drive circuit 6 so that the magnetic tape 5 stops (steps S1-5, S1-6).

As described above, the rotation of the head drum and the running of the magnetic tape, which have been performed for every n screens of the video signal, are performed by n times.
Xm screens, so that the wear of the magnetic head, the magnetic tape, and the running system can be reduced. Also, Japanese Unexamined Patent Publication No.
The visitor recording apparatus disclosed in Japanese Patent No. 10088 is provided with a visitor annunciator for notifying that a visitor has arrived, and when the visitor annunciator detects a visitor, a VTR is driven to record an image.

[0013] In addition, a lime-lapse VTR is disclosed in
As a function similar to the visitor recording apparatus disclosed in Japanese Patent Application Publication No. 261284/1990, there is an operation function of alarm recording. In the alarm recording, an intermittent recording operation is usually performed, and when an alarm signal is input, a normal recording operation is performed. FIG. 6 shows a block diagram of another example of the related art. 4, the same components as those of FIG. 4 are denoted by the same reference numerals, and the description thereof will be omitted.

The control circuit 11 receives an alarm signal from a control terminal Tcont. When the alarm signal is not input, the control circuit 11 controls the memory circuit 1, the head drum driving circuit 7, and the capstan driving circuit 6 to perform an intermittent recording operation at a first interval (for example, at an interval of 8 seconds). At the time of signal input, the memory circuit 1, the head drum drive circuit 7, and the capstan drive circuit 6 are controlled to perform a recording operation at a second interval (for example, 0.5 second interval).

FIG. 7 shows a flowchart of another conventional control circuit. The control circuit 11 monitors the control terminal Tcont (step S2-1), and performs control in step S2-1.
In the state where the alarm signal is not input, the memory circuit 1, the head drum driving circuit 7, and the capstan driving circuit 6 are controlled to intermittently record the video signal at the first interval. (Step S2-2).

When an alarm signal is input in step S2-1, the memory circuit 1, the head drum driving circuit 7
Then, the capstan drive circuit 6 is controlled to intermittently record the video signal at the second interval shorter than the first interval (step S2-3). As described above, when the alarm signal is input, the video signal is recorded at the second interval shorter than the first interval, so that a moving object in the video signal can be recognized.

[0017]

However, in the intermittent recording apparatus disclosed in JP-A-6-261284 as shown in FIG. 4, a magnetic head, a magnetic tape, and a running system are controlled each time a video signal is recorded on one screen. Eliminates the need for magnetic heads,
The wear of the magnetic tape and running system can be reduced,
Since the video signal is recorded at a predetermined interval, there is a problem that when the motion of the video signal is large, an object having a large motion is not recorded. Further, since the memory is used only for intermittent recording, there is a problem that it is not economical.

In a VTR as shown in FIG. 6, when an alarm signal is inputted, the intermittent interval of the video signal is switched from a first interval to a second interval shorter than the first interval. After the alarm signal is obtained, the image information increases, and even objects with large movements can be recorded.However, the image information immediately before the object movement becomes large is small, and the process until the object movement becomes large. There was a problem that it was not possible to recognize the

The present invention has been made in view of the above points, and has as its object to provide a video signal recording apparatus capable of recording a video before an alarm signal is supplied at a high density.

[0020]

According to the first aspect of the present invention, there is provided a video recording apparatus comprising: a storage means for storing an input video signal; and a recording means for recording the video signal stored in the storage means on a recording medium. Wherein output means for extracting a video signal at predetermined intervals from the video signal stored in the storage means between the storage means and the recording means and supplying the extracted video signal to the recording means is provided.

According to the first aspect, the video signal is extracted at predetermined intervals from the video signal stored in the storage means by the output means and supplied to the recording means, so that the video signal stored in the storage means is extracted. Since the interval can be shorter than the interval of the video signal recorded in the recording unit, even if the interval of the video signal recorded in the recording unit is shortened by the control signal, the interval of the video signal stored in the storage unit is obtained at the time when the control signal is supplied. The video signal can be recorded in the recording means at the same interval, so that the video before the control signal is supplied can be recognized at a short interval.

According to a second aspect of the present invention, there is provided a control unit for controlling an interval of a video signal extracted from the video signal stored in the storage unit by the output unit in accordance with a control signal supplied from outside. . According to the second aspect, by controlling the video extraction interval of the output means according to the control signal by the control means, the video signal stored in the storage means is recorded at the same interval when the control signal is supplied. It can be recorded on the means, so that the video before the control signal is supplied can be recognized at short intervals.

According to a third aspect of the present invention, the image processing apparatus further comprises input means for extracting a video signal from the input video signal at predetermined intervals and supplying the video signal to the storage means. According to claim 3,
By extracting the video signal at a predetermined interval from the input video signal by the input unit and supplying the extracted video signal to the storage unit, the degree of freedom in setting the interval of the video signal to be recorded in the recording unit can be improved.

According to a fourth aspect of the present invention, the interval of the video signal extracted from the input video signal by the input means is controlled by the control means in accordance with the control signal. According to the fourth aspect, by controlling the interval of the video signal extracted from the input video signal by the input means according to the control signal, the degree of freedom in setting the interval of the video signal to be recorded in the recording means is improved. it can.

According to a fifth aspect of the present invention, in accordance with the control signal, the control means controls an interval of a video signal stored from a video signal supplied from the input means to the storage means. According to the fifth aspect, by controlling the interval between the video signals stored in the storage unit in accordance with the control signal, it is possible to improve the degree of freedom in setting the interval between the video signals to be recorded in the recording unit.

[0026]

FIG. 1 is a block diagram showing an embodiment of the present invention. The video recording device 100 of the present embodiment mainly includes a video input unit 110 and a video recording unit 120. The video input unit 110 has a video signal input terminal Tin
The video signal extracted at predetermined intervals from the video signal supplied from is supplied to the video recording unit 120 at predetermined intervals. The image input unit 110 extracts an image signal at a first interval from the input image signal supplied to the input terminal Tin.
1. a memory circuit 112 for storing a video signal at a second interval from the video signal extracted by the input circuit 111; an output circuit 113 for extracting a video signal at a third interval from the video signal stored in the memory circuit 112; An input circuit 111, a memory circuit 112, and an input control circuit 114 for controlling first to third intervals set in the output circuit 113 in accordance with a recording control signal supplied from the control terminal Tcont.

An input video signal is supplied to the video signal input terminal Tin from a monitoring camera or the like. The input video signal supplied to the video signal input terminal Tin is supplied to the input circuit 111. The input circuit 111 extracts a video signal from the input video signal supplied from the video signal input terminal Tin at every first interval according to the first interval control signal supplied from the input control circuit 114. The video signal extracted by the input circuit 111 is supplied to a memory circuit 112 and an output circuit 113.

The memory circuit 112 sequentially converts the video signal extracted by the input circuit 111 at the first interval at a second interval set in accordance with the second interval control signal supplied from the input control circuit 114. accumulate. The video signal stored in the memory circuit 112 is output to the output circuit 11 every time a predetermined screen is stored.
3 is supplied. The output circuit 113 is a memory circuit 112
The video signal is extracted at a third interval set in accordance with the third interval control signal supplied from the input control circuit 114 from the video signal supplied from. The video signal extracted from the output circuit 113 is supplied to the video recording unit 120 as a recording video signal.

The video recording section 120 includes a modulation circuit 121 for converting the video signal supplied from the video input section 110 into a recordable signal, a recording amplifier 122 for amplifying the video signal modulated by the modulation circuit 121, and a recording amplifier 122. A magnetic head 123 that generates a magnetic field according to the video signal amplified by
A rotating drum 124 for fixing the magnetic head 123, a drum motor 125 for rotating the rotating drum 124, a drum driving circuit 126 for driving the drum motor 125, a capstan motor 127 for running the magnetic tape, and a capstan for driving the capstan motor 127 Drive circuit 12
8. Drum drive circuit 126 and capstan drive circuit 1
The recording control circuit 129 supplies a drive command to the recording control circuit.

The modulation circuit 121 is supplied with thinned-out video signals from the output circuit 113 of the video input unit 110 at predetermined intervals. The modulation circuit 121 includes the video input unit 11
The video signal supplied from the 0 output circuit 113 is converted into a signal having characteristics that can be favorably recorded on the magnetic tape 130 and supplied to the recording amplifier 122. The recording amplifier 122 amplifies the signal modulated by the modulation circuit 121 and supplies the amplified signal to the magnetic head 123. The magnetic head 123 is a rotating drum 1
24.

The rotating drum 124 includes a drum motor 125
, And rotates according to the rotation of the drum motor 125. As the rotating drum 124 rotates, the magnetic head 123 scans the surface of the magnetic tape. Further, the magnetic tape 130 is held between the rotation shaft of the capstan motor 127 and the capstan roller, and runs as the capstan motor 127 rotates. Magnetic head 1
23 scans the surface of the running magnetic tape and records a video signal.

At this time, the drum motor 125 is driven at a constant rotation speed by the drum drive circuit 126, and the capstan motor 127 is driven by the capstan drive circuit 128.
Thus, the magnetic tape 130 is driven to have a constant running speed. The drum driving circuit 126 and the capstan driving circuit 128 are connected to the recording control circuit 129, and are controlled according to a driving command supplied from the recording control circuit 129.

The recording control circuit 129 is connected to the video input unit 110
And a driving command is supplied to the drum driving circuit 126 and the capstan driving circuit 128 in accordance with a control signal supplied from the input control circuit 114. Here, the operation of the input control circuit 114 will be described. FIG. 2 shows an operation flowchart of the input control circuit according to one embodiment of the present invention.

In the input control circuit 114, the control terminal Tcont
(Step S3-1), and the control terminal Tcont
Is supplied with an alarm signal, the input control circuit 114
Refers to a preset operation mode (step S
3-2). If the operation mode is the intermittent recording operation mode in step S3-2, the output interval of the output circuit 113 is controlled so that the data is recorded on the recording medium at the interval recorded in the memory circuit 112 (step S3-3). Note that the output interval of the video signal from the output circuit 113 is set to an interval shorter than a preset normal state.

At this time, the first to third interval control signals are:
It is set to be the shortest when an alarm signal is input. If the continuous operation mode is set in step S3-2, the output circuit 113 transmits the video signal directly supplied from the input circuit 111 to the video recording unit 1.
20 (step S3-4).

Next, when the alarm signal is released (step S3-5), the output interval of the video signal of the output circuit 113 is reset to a preset normal state. In addition,
At this time, the input control circuit 114 gives an operation instruction to the recording control circuit 129 of the video recording unit 120 during the period when the video signal is output from the output circuit 113, and controls the recording to a recordable state.

An instruction signal is supplied from the input control circuit 114 to the recording control circuit 129 in accordance with the timing at which the video signal is read from the output circuit 113, and the drum drive circuit and the capstan drive circuit are driven.
3 is sequentially recorded on a magnetic tape. FIG. 3 shows an operation explanatory diagram of one embodiment of the present invention. FIG.
3A is an input video signal, FIG. 3B is an output video signal of the input circuit 111, FIG. 3C is an output video signal of the memory circuit 112, and FIG. 3D is an output circuit 1 when an alarm signal is released.
13 shows an output video signal, and FIG. 3E shows an output video signal of the output circuit 113 when an alarm signal is supplied.

In the input circuit 111, as shown in FIG. 3B, a continuous video signal A as shown in FIG.
For example, video signals a1 to a5 are captured at intervals of time T0. The video signals a1 to
As shown in FIG. 3C, a5 is grouped into video signals (a1, a2), (a3, a4), and (a5, a6) every two cycles, and then the video signals (a1, a2), (a3 , A
4) and (a5, a6) are continuously output.

When the alarm signal is released, the output circuit 113 reads a video signal at a predetermined interval T10 from the video signal output from the memory circuit 112 shown in FIG. Therefore, as shown in FIG. 3D, the video signals (a1, a2) and (a5, a6) are sequentially supplied to the video recording unit 120 and recorded. When an alarm signal is supplied, the output circuit 113 outputs the video signal from the memory circuit 112 shown in FIG. 3C as it is. Therefore, as shown in FIG. 3E, the video signals (a1, a
2), (a3, a4) and (a5, a6) are sequentially supplied and recorded.

As described above, according to the present embodiment, when an alarm signal is supplied, the thinned-out video signal stored immediately before the alarm signal is supplied to the memory circuit 112 is output from the output circuit 113 as it is. Therefore, the video immediately before the alarm signal is supplied can be recorded in detail. The interval at which the video signal is thinned out by the input circuit 111, the memory circuit 112, and the output circuit 113 can be freely adjusted by setting.

[0041]

As described above, according to the first aspect of the present invention, the video signal is extracted at predetermined intervals from the video signal stored in the storage means by the output means and supplied to the recording means. Since the interval between the video signals stored in the storage unit can be shorter than the interval between the video signals recorded in the recording unit, the control signal is supplied even when the interval between the video signals recorded in the recording unit is shortened by the control signal. At the point in time, the video signal stored in the storage means can be recorded in the recording means at the same interval, so that the video before the control signal is supplied can be recognized at a short interval.

According to the second aspect, the control means controls the video extraction interval of the output means in accordance with the control signal, so that the video signal stored in the storage means is kept as it is when the control signal is supplied. It can be recorded on the recording means at intervals, and thus has the advantage that images before the control signal is supplied can be recognized at short intervals. According to the third aspect, the video signal is extracted at a predetermined interval from the input video signal by the input unit and supplied to the storage unit, so that the degree of freedom in setting the interval of the video signal to be recorded in the recording unit can be improved. Features such as

According to the fourth aspect, by controlling the interval of the video signal extracted from the input video signal by the input means in accordance with the control signal, the interval of the video signal to be recorded in the recording means can be freely set. It has features such as improvement in degree. According to the fifth aspect, the degree of freedom in setting the interval of the video signal to be recorded in the recording unit can be improved by controlling the interval of the video signal stored in the storage unit in accordance with the control signal. Has features.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is an operation flowchart of an interval control circuit according to one embodiment of the present invention.

FIG. 3 is an operation explanatory diagram of one embodiment of the present invention.

FIG. 4 is a block diagram of a conventional example.

FIG. 5 is an operation flowchart of a conventional control circuit.

FIG. 6 is a block diagram of another example of the related art.

FIG. 7 is an operation flowchart of another conventional control circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 video recording device 110 video input unit 111 input circuit 112 memory circuit 113 output circuit 114 input control circuit 120 video recording unit 121 modulation circuit 122 recording amplifier 123 magnetic head 124 rotating drum 125 drum motor 126 drum driving circuit 127 capstan motor 128 cap Stun drive circuit 129 Recording control circuit 130 Magnetic tape

Claims (5)

[Claims] 1. A video recording apparatus comprising: a storage unit that stores an input video signal; and a recording unit that records a video signal stored in the storage unit on a recording medium. A video recording apparatus comprising: an output unit that extracts a video signal at predetermined intervals from the video signal stored in the storage unit and supplies the video signal to the recording unit. 2. The apparatus according to claim 1, further comprising control means for controlling an interval between video signals extracted from the video signals stored in said storage means by said output means in accordance with a control signal supplied from outside. The video recording device as described in the above. 3. The video recording apparatus according to claim 1, further comprising an input unit that extracts a video signal from the input video signal at predetermined intervals and supplies the video signal to the storage unit. 4. The video recording apparatus according to claim 2, wherein the control unit controls an interval between video signals extracted from the input video signal by the input unit in accordance with the control signal. 5. The image processing apparatus according to claim 2, wherein the control unit controls an interval between video signals stored from video signals supplied from the input unit to the storage unit in accordance with the control signal. The video recording device according to any one of the preceding claims.