KR20000021148A - Search method using time in monitoring system - Google Patents

Abstract

PURPOSE: A method is provided to search monitored images more rapidly by recording the monitored images together with codes and by using recording time coded when searching the monitored images. CONSTITUTION: Present recording time is coded together with a proper number(306).Monitored images are recorded on a video track of a video tape and recording is carried out on a control track(308). Search information including recording time from a computer when identifying a recorded monitoring image signal is inputted(312, 314). A control pulse and a vis pulse read out by reproducing a video tape are decoded to be compared with the inputted record time(316). A reproduction is started from an interval corresponding to the inputted record time and the decoded signal(322).

Description

Method for searching using recording time in a securty system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a search method using time in a surveillance system. In particular, the present invention relates to a position that a user wants to find in a surveillance system for recording an unmanned surveillance camera image in a bank or the like using a digital video cassette recorder (hereinafter, referred to as DVCR). The present invention relates to a search method using time in a surveillance system that can be easily searched using recorded time.

In general, a surveillance system is a device installed for security in a place where surveillance such as a bank is required. The surveillance system monitors a place using an unmanned surveillance camera and stores an image monitored by the surveillance camera through a predetermined recording means. As a useful equipment that can be identified later, it is widely used and used.

As shown in FIG. 1, the surveillance system includes a plurality of cameras 100 for capturing an environment in place, a DVCR 300 for storing and reading images captured from the camera 100, and a camera ( And a computer 200 for controlling the overall operation of the surveillance system by controlling the DVCR 300 based on the video signal applied from the apparatus 100.

In this configuration, the camera 100 outputs a captured image signal by photographing a subject in each field environment, and the computer 200 is a main controller for controlling the overall operation of the surveillance system. The video signal is processed into a digital video signal, the DVCR 300 is controlled and recorded, and the recorded video signal is displayed and confirmed through a monitor of the computer 200.

The digital data bit stream (DVHS) of the DVCR 300 is a video and audio compressed in the form of a 20-bit sync signal, a 30-bit identification signal, and a 770-bit moving picture expert group (MPEG). One data block includes 125 data blocks, 80 sync bits with internal parity signals, and 11 sync blocks with external parity signals instead of the 770-bit video and audio signals. The track signal is constructed.

In addition, a predetermined block synchronization signal and a 6000-bit preamble signal are added to the front of the aforementioned 136 sync blocks, and a 5000-bit post-amble signal is added to the rear.

On the other hand, at the time of recording, the one-digit digital data bit stream described above is recorded in one track in synchronization with the phase of the head drum based on the block synchronizing signal, and the digital data bit stream at this time is not analog data but analog data. It is handled and recorded using the deck mechanism of the conventional analog video cassette recorder by accurately synchronizing the above-described block synchronizing signal with the phase of the head drum.

On the other hand, if you briefly look at the configuration of the DVCR 300, the microcomputer 310 for controlling the overall operation of the DVCR, a deck unit for recording and playing the digital data bit stream applied under the control of the microcomputer 310 ( 320, the sub-microcom 330 and the sub-microcom 330 which control the encoding and decoding of the digital video signal applied from the computer 200 under the control of the microcomputer 310 and perform the communication control. A digital signal processing unit 340 for encoding a digital signal into a digital bit stream, decoding and outputting a digital bit stream applied from the deck unit 320, and a universal asynchronous transceiver (UART) for interfacing with the computer 300. and an interface unit 350 using a receiver / transmitter.

In the monitoring system having such a configuration, when searching for a desired section, there is a problem in that the user must find the desired section while looking at a screen for playing the desired section.

On the other hand, the control signal in the video cassette recorder (Control Pulse) is recorded at the bottom of the video tape, i.e., the control track (0.75 mm), and recorded and detected by the control head as a bipolar pulse of frequency 30 Hz.

When recording, the control signal divides the vertical sync signal of the video signal into 1/2, and then records it on the control track. During playback, the control signal is detected and compared with the reference signal 30 Hz to phase the Capstan Motor. It is supposed to be controlled.

That is, during recording, the control signal in the form of a square wave extracted from the vertical synchronizing signal is accurately recorded on the video tape once per cylinder rotation, that is, once every 1/30 second, and the control recorded by the control head during playback. The signal is read to control the timing of the capstan motor and rotating head cylinder that drives the videotape.

On the other hand, the VHS Index Search System (VISS) used for recording is a VHS Uniform Index (INDEX) signal, which is recorded on tape as an index signal based on converting a waveform of a normal control pulse at the beginning of recording. When recording, as a vis signal, 62 control pulses with a high level and a low level of about 3 to 7 are recorded, and a normal control pulse with a high level and a low level of 7 to 3 is described after the bis signal. Is recorded.

According to the present invention, the recording time is encoded and recorded in a predetermined format by using two control signals having different duty, so that the desired recording time can be searched more quickly by using the recording time as a keyword during playback. I would like to present.

The present invention has been made in order to solve the above-mentioned conventional problems, the object of which is to record the video recorded with a control signal when recording the video monitored in the surveillance system using the DVCR as a recording means, The present invention provides a search method using time in a surveillance system that enables a faster search using a recording time that is hatched and recorded when searching for a surveillance video.

1 is a block diagram of a monitoring system employed in accordance with the present invention.

2A is a waveform diagram illustrating a control pulse and a bis pulse employed in accordance with the present invention.

2B is a data format for recording time information recorded according to the present invention.

3 is a flow chart illustrating a search process in accordance with the present invention.

<Explanation of symbols for main parts of the drawings>

100: camera 200: computer

300: DVCR 310: Microcomputer

320: deck portion 330: sub-microcom

340: digital signal processing unit 350: interface unit

A search method using time in a surveillance system according to the present invention is a recorded video search method in a surveillance system for centrally controlling a video signal monitored from a surveillance camera with a computer to record using a digital video cassette recorder. Encoding a current recording time with a unique number of a surveillance camera when recording a video signal;

The control track is recorded by recording the monitored image from the surveillance camera corresponding to the unique number on a video track of a video tape and simultaneously using the difference between the duty ratios of the control pulse and the bis pulse that use the encoded signal in a video cassette recorder. A recording process comprising the step of recording the video data, receiving recording information including a recording time desired to be searched from the computer when the recorded surveillance video signal is checked, and a control pulse and a bis pulse read out by reproducing the video tape. And a reproducing process including the step of decoding and comparing with the received recording time, and starting the reproduction from the section where the decoded signal and the input recording time coincide.

The above objects and various advantages of the present invention will become more apparent from the preferred embodiments of the invention described below with reference to the accompanying drawings by those skilled in the art.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2A is a waveform diagram showing a control pulse and a bis pulse used in the present invention. As shown in the figure, a general control pulse has a high level section of 60 ± 5%, and a bis pulse is a high level section. It takes up 27.5 ± 2.5% and uses data "0" and data "1" respectively.

FIG. 2B is a data format for recording time information according to the present invention. The header area includes 11 bits of “01111111110”, and the time information is composed of a total of 40 bits by allocating bits by year, month, day, hour, minute, and second. Finally, the unique number of the surveillance camera is allotted to 9 bits to form a total of 60 bits.

Next, a search process according to the present invention will be described in detail with reference to the accompanying flowchart of FIG. 3.

First, FIG. 3 illustrates a recording process using time information and a search and play process using time information.

First, in the recording mode (step 300), each surveillance image applied from the camera 100 is converted into a digital image signal (for example, a still image screen for each frame) in the computer 200, and sequentially a predetermined control signal (camera) With a unique number), is applied to the DVCR 300 (step 302).

Then, in the DVCR 300, the digital video signal applied through the interface unit 350 under the control of the sub-microcom 330 is encoded into the digital bit stream described above by the digital signal processing unit 340, and thus the deck unit 320. The deck unit 320 records the digital bit stream applied under the control of the microcomputer 310 to the video track of the video cassette tape (step 304).

In addition, the microcomputer 320 encodes the current time and the camera unique number into the data format of FIG. 2B described above (step 306), and records the control track of the video cassette tape with the control head in the deck unit 320 (step 308). ).

Meanwhile, if the recording time and the unique number of the monitored camera are recorded together with the monitored video on the video cassette tape through the above-described recording process, the user can quickly search for a desired section by using the recording time. It becomes possible.

On the other hand, commands that can be input by the keyboard of the computer 200 in order to control the operation of the DVCR 300 are general power on / off key, PLAY key, stop ( STOP key, PAUSE key, fast forward (FF) key, rewind (REW) key, REC key, EJECT key, SEARCH key, SPEED key, etc. The keys may be selected by using a predetermined key operation assigned to the keyboard, by clicking an icon on a predetermined program controlling the DVCR 300, or by using a pull-down menu.

Accordingly, in order to search for the surveillance video recorded based on the above-described recording process, first, after selecting the search key, the user can use the keyboard of the computer 200 to record the recording time information (year, Month, day, hour, minute, second, camera number) (step 310).

At this time, the control signals are transmitted to the DVCR 300 based on the serial communication of the computer 200, and the interface unit 350 of the DVCR 300 receives the control signals applied based on the serial communication. It is interfaced with to receive input.

Next, the microcomputer 310 of the DVCR 300 receives the above-described recording time information and then controls the deck unit 310 to search for a recorded image corresponding to the input recording time information. After rewinding, the mode is switched to the fast-forward mode (step 312), and the video tape is fast-forwarded in all directions while being read through the control head (step 314) to compare the applied recording time information with the input recording time information ( Step 316).

At this time, if the recording time information read out through the control head and the input recording time information do not match, it is determined whether it is the end of the video cassette tape (step 318), and if not, the process returns to step 316 described above. If the read recording time information and the input recording time information match, it is determined that the end of the video cassette tape, that is, even if the fast forwarding ends, the read recording time information does not match the input recording time information. Is displayed (step 320), and the search process is terminated.

On the contrary, when the recording time information read out through the control head and the input recording time information in step 316 coincide with each other, the microcomputer 310 controls the deck unit 320 to stop the fast forwarding and reproduce the same. The control mode is switched to reproduce the surveillance video signal recorded according to the input recording time information (step 322).

Then, the read surveillance video desired by the user is transferred to the computer 200 through the digital signal processor 340 and the interface unit 350, and the computer 200 monitors the digital video signal applied from the DVCR 300. After the display, the user can quickly check the desired surveillance image through the monitor of the computer 200.

Meanwhile, the recording time information displays the recording time information along with the screen which is played at high speed when the DVCR 300 performs the fast play mode so that the user can select a scene to be monitored while checking the screen being played through the fast play mode. It can be seen that the modification can be easily carried out.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

As described above, according to the present invention, the recording time information, including the current time and the unique number of the surveillance camera, is recorded on the control track of the video cassette recorder when recording the surveillance video in a surveillance system used in a place where surveillance such as a bank is required. By encoding and recording, it is possible to quickly search for a section to be checked by using such recording time information during playback or search.

Claims (2)

A method of searching recorded video in a surveillance system in which a video signal monitored by a surveillance camera is centrally controlled by a computer and recorded using a digital video cassette recorder. Encoding a current recording time with a unique number of a surveillance camera when recording the monitored video signal; The control track is recorded by recording the monitored image from the surveillance camera corresponding to the unique number on a video track of a video tape and simultaneously using the difference between the duty ratios of the control pulse and the bis pulse that use the encoded signal in a video cassette recorder. A recording process comprising the step of recording on; Receiving search information including a recording time to be searched from the computer when checking the recorded surveillance video signal; Replaying the video tape to decode the control pulses and the bis pulses to be compared with the input recording time; A search method using time in a surveillance system comprising a playback process comprising the step of starting playback from a section in which a decoded signal and an input recording time coincide. The method of claim 1, wherein the encoded signal is configured in a format including a header of a predetermined bit, a recording time having a year, month, day, hour, minute, second of a predetermined bit, and a camera unique number of the predetermined bit. Searching method using time in a surveillance system.