KR101050448B1 - Pre-alarm buffering method and device according to time length of pre-alarm data - Google Patents

Abstract

According to the present invention, a buffer area for storing pre-alarm data is divided into a long time pre-alarm data storage space and a short time (real-time) pre-alarm data storage space and stored in each storage area, and then stored based on a key frame. The present invention relates to a pre-alarm buffering method and apparatus according to a length of time for pre-alarm data to improve recording or reproducing speed by simultaneously storing short and long time pre-alarm data on a hard disk.

According to the present invention, the embedded digital video recorder can simultaneously store and store the respective storage queues for the short time and long time pre-alarm data, and the time for recording and storing the video data as the short time and long time pre-alarm data are simultaneously stored. And the time for reproduction can be shortened.

Embedded, DVR, storage queue, pre-alarm, time, buffering, SDRAM, SDRAM

Description

Method and apparatus for pre-alarm buffering according to time length of pre-alarm data             

1 is a schematic view showing the internal configuration of a conventional digital video recorder for surveillance,

FIG. 2 is a diagram illustrating a structure of an SDRAM for buffering pre-alarm data according to a length of time of the pre-alarm data in an embodiment of the present invention.

3 is a flowchart illustrating a pre-alarm buffering method according to a time length of pre-alarm data according to an embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

100: digital video recorder 110: device interface

120: DVR control unit 130: hard disk

140: disk driver 150: network interface

160: memory

The present invention relates to a method and apparatus for pre-alarm buffering according to the length of time of pre-alarm data in a video digital recorder. More particularly, the present invention relates to a buffer area storing pre-alarm data for a long time. Free and short time (real time) pre-alarm is divided into the storage space of the pre-alarm data and stored in each storage area, and pre and short time and long time pre-alarm data are stored on the hard disk at the same time to improve recording or playback speed. A method and apparatus for pre-alarm buffering according to a length of time of alarm data.

1 is a configuration diagram schematically showing the internal configuration of a conventional digital video recorder for surveillance.

The conventional surveillance digital video recorder includes a device interface 110 for connecting and connecting a plurality of surveillance cameras and sensors, and a DVR controller 120 for performing an event detection operation and an audio and video data recording operation accordingly. ), The hard disk 130 for recording and storing the event detection audio and video data as a data file by the operation control of the DVR controller 120, and backing up the data files stored in the hard disk 130 to an optical disk such as a CD-RW. A disk driver 140 for receiving, a network interface 150 for connecting to a client through a network, and a memory 160 for storing information necessary for controlling the operation of the DVR controller 120 are included.

When the DVR system 100 configured as described above records and stores an event image on the hard disk 130, the DVR system 100 converts the video signals inputted from a plurality of surveillance cameras into digital image data, encodes, compresses and compresses the image data to the hard disk 130. Save it. In addition, after converting a video frame representing the event video to a reduced image, the converted reduced images are recorded and managed as a preview search index file. And a preview search operation for intermittently searching for an event image recorded and stored in the hard disk 130 through an interface with a client connected and connected through the network interface 150. The reduced image recorded in the preview search index file is read and quickly provided to the client.

However, in the case of the embedded DVR system 100 having the above-described configuration and function, a function of storing pre-alarm data when recording and storing image data on the hard disk 130 is required. do. However, the storage of pre-alarm data is divided into regions requiring real-time pre-alarms of several seconds and regions requiring long-term low-speed pre-alarms for 15 minutes and 1 frame per second (fps). At the same time, the function of supporting the case is not provided.

In addition, unlike the PC (Personal Computer) based DVR, the existing embedded VDR system 100 does not support the pre-alarm function for a long time, and even if it is supported, the hard disk 130 is not based on the SDRAM buffer. It provides long time pre alarm function as stored data.

Therefore, since the image data is recorded and stored together with the pre-alarm data on the hard disk 130, the time for storing and storing the record becomes long, and the pre-alarm data is also used to read the recorded and stored image data from the hard disk 130. Since the first read and the image data is read accordingly, the playback time is also disadvantageous than the PC-based VDR.

In order to solve the above problems, the present invention stores a buffer area for storing pre-alarm data into a storage space for a long time pre-alarm data storage space and a short time (real-time) pre-alarm data, and stores them in each storage area. The purpose of the present invention is to provide a method and a device for pre-alarm buffering according to the length of time of pre-alarm data, which improves the recording or reproducing speed by simultaneously storing short- and long-term pre-alarm data based on key frames on the hard disk. have.

The pre-alarm buffering device for a digital video recorder according to the present invention for achieving the above object is a pre-alarm buffering device for a digital video recorder that simultaneously stores short-time pre-alarm data and long-term pre-alarm data at the time of recording and storing image data. The medium storing the short time pre-alarm data and the long time pre-alarm data may be divided into a long time pre-alarm data storage space A and a short time pre-alarm data storage space B.

In addition, the pre-alarm buffering method according to the time length of the pre-alarm data according to another object of the present invention, in the pre-alarm buffering method for storing the short-term pre-alarm data and the long-term pre-alarm data at the same time when recording and storing the image data, A first step of recognizing a record storage alarm according to a command relating to record storage of image data; A second step of dividing the image data into a long time pre-alarm data storage queue and a short time pre-alarm data storage queue, and obtaining a key frame at a time specified by a user; Determining whether there is a short-time pre-alarm data indexed by the keyframe; And storing the long time pre-alarm data indexed by the keyframe on the hard disk, and storing the short-time pre-alarm data indexed by the keyframe on the hard disk. It is characterized by including four steps.

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

First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings.

In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

FIG. 2 is a diagram illustrating a structure of an SDRAM for buffering pre-alarm data according to a time length of pre-alarm data in an embodiment of the present invention.

The structure of the SDRAM according to the present invention is divided into a storage space A for a long time low-speed pre-alarm data and a short time real-time pre-alarm data storage space B.

Accordingly, the DVR control unit 120, with respect to the image data input from the plurality of surveillance cameras, the I frame corresponding to the inter frame is stored in the storage queue Qeue of the low speed pre-alarm data for a long time. P or B frame corresponding to the frame) is separated into the storage queue of short-time real-time pre-alarm data and waits. That is, the long time low speed pre alarm data is stored in the long time low speed pre alarm data storage space (A) as one or two key frames per second, and the short time real time pre alarm data stores the short time real time pre alarm data. Each is stored in space B.

Each key frame stored in the long time low speed pre alarm data storage space A is stored with the position information of the short time pre alarm data storage queue. In this case, I frame is compressed by using only spatial compression in MPEG-encoded video data, whereas P or B frames are based on I frames and employ both time and spatial compression simultaneously. Can be increased, but cannot be restored to its own data and must refer to an I frame. In addition, the keyframe has a function as a time index.

Next, the pre-alarm buffering method according to the length of time of the pre-alarm data according to the embodiment of the present invention will be described with reference to the flowchart of FIG. 3.

First, when power is applied to the VDR system and operated, the VDR controller 120 receives image data photographed from a plurality of surveillance cameras and displays the image data through a display unit (not shown) (S302).

Therefore, when the screen is to be recorded while checking the displayed image data, the user inputs a command for recording and storing through key input.

According to a command for recording and storing the image data, a recording storage alarm is generated and transmitted to the VDR controller 120 (S304).

Accordingly, when a recording storage alarm is generated, the VDR controller 120 separates the received image data into a long time pre-alarm data storage queue and a short time pre-alarm data storage queue, and obtains a key frame corresponding to a user-specified time. Check (S306).

As described above, I frames of video data are queued in the long-term pre-alarm data storage queue, and P or B frames of video data are queued in the short-term pre-alarm data storage queue.

Since key frames of the long-term pre-alarm data storage queue are stored as I frames at 1 or 2 frames per second, when a record storage alarm occurs, the key frames are obtained through a user-specified time and function as a time index.

Therefore, when there is a short time pre-alarm data indexed by the key frame (S308), the VDR controller 120 stores the long time pre-alarm data on the hard disk (HDD) and refers to the key frame with reference to the key frame. The indexed real-time pre-alarm data to be indexed is stored together in the hard disk (HDD) (S310).

However, if there is no short-time pre-alarm data indexed by the keyframe, the VDR controller 120 stores only the low-speed long-time pre-alarm data waiting in the long-term pre-alarm data storage queue on the hard disk HDD (S312).

When the image data is compressed in MPEG, I frames are set to be encoded by two frames per second, and then each keyframe is mapped to a short time pre alarm data storage area of 1 second when the storage of the long time pre alarm data is 1 fps. Therefore, when the storage of the long time pre alarm data is 2 fps, each keyframe is mapped to a short time pre alarm data storage area of 0.5 seconds.

In addition, the size of the long time pre-alarm data storage queue and the short time pre-alarm data storage queue can be variably adjusted so that the user can arbitrarily set the data storage time.

As described above, according to the present invention, the buffer area of the SDRAM storing the pre-alarm data is divided into the storage space of the long-term low speed pre-alarm data and the storage space of the short-term (real-time) pre-alarm data, and the corresponding pre-alarm is stored in each storage area. By storing the data, a pre-alarm buffering method and apparatus can be realized according to the length of time of the pre-alarm data, which simultaneously stores the short- and long-term pre-alarm data to improve the recording or reproducing speed.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments.

The scope of protection of the present invention should be construed according to the following claims, and all technical ideas falling within the scope of the same shall be construed as falling within the scope of the present invention.

As described above, according to the present invention, the embedded digital video recorder can simultaneously store the respective storage queues for the short time and long time pre-alarm data.

In addition, since the short time and long time pre-alarm data are stored at the same time, it is possible to shorten the time for recording and reproducing the video data.

Claims (10)

In the pre-alarm buffering device of a digital video recorder which simultaneously stores short-term pre-alarm data and long-term pre-alarm data at the time of recording and storing image data, The medium for storing the short time pre-alarm data and the long time pre-alarm data may be divided into a long time pre-alarm data storage space A and a short time pre-alarm data storage space B, For the video data, I frame is a long time data storage queue in the long time pre-alarm data storage space A, and P or B frames are short time data stored in the short time pre alarm data storage space B. A pre-alarm buffering device for a digital video recorder, characterized by being separated into queues. delete The method of claim 1, And the long time pre-alarm data is stored in the long time pre-alarm data storage space (A) as one or two key frames per second. The method of claim 1, And a size of the long time data storage queue and the short time data storage queue is set by the user to variably adjust the data storage time. The method of claim 3, wherein And the key frame has position information of the short-time pre-alarm data for indexing. In the pre-alarm buffering method of simultaneously storing short-term pre-alarm data and long-term pre-alarm data when recording and storing video data, A first step of recognizing a recording storage alarm in accordance with a command regarding recording and storing of the image data; A second step of dividing the video data into a long time pre-alarm data storage queue and a short time pre-alarm data storage queue, and obtaining a key frame corresponding to a time designated by a user; Determining whether there is short-term pre-alarm data indexed by the keyframe; And When the short-time pre-alarm data indexed by the keyframe exists, the long-term pre-alarm data is stored on the hard disk (HDD), and the corresponding short-term pre-alarm data indexed by the keyframe is stored on the hard disk (HDD). And pre-alarming the pre-alarm data according to the time length of the pre-alarm data. The method of claim 6, If the short time pre-alarm data indexed by the keyframe does not exist, only the long time pre-alarm data waiting in the long time pre-alarm data storage queue is stored in the hard disk (HDD). Pre-alarm buffering method over time length. The method of claim 6, With respect to the video data, an I frame is stored in the long time pre alarm data storage queue, and a P or B frame is stored in the short time pre alarm data storage queue. How to buffer alarms. The method of claim 6, The pre-alarm pre-alarm data is stored in the long-term pre-alarm data storage queue as one or two key frames per second. The pre-alarm buffering method according to the length of time of the pre-alarm data. The method of claim 9, And the key frame has position information of the short-time pre-alarm data for indexing.

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